Ghoul Vibrations: press release. [Archive]

Admin

14th May 2007, 01:02 PM

PRESS RELEASE

April 2007

GHOUL VIBRATIONS…

Ground breaking research is to be carried out, in a world first this May, to discover whether low level sounds waves known as infrasound could be the real reason behind haunting experiences.

From Friday 11th to Sunday 20th May a team of experts, led by parapsychologist Dr Ciaran O’Keeffe and Para.Science expert Steve Parsons, will be conducting a series of experiments at the reputedly haunted location of Mary King’s Close in Edinburgh as part of the hugely popular paranormal festival Mary King’s Ghost Fest.

During the research events, members of the public will be guided deep below the Royal Mile in Edinburgh, to the series of underground closes (streets), rooms and spaces that comprise the award winning Mary King’s Close visitor attraction which date back to the 17th century and has been seen documented tales of ghostly apparitions dating back to 1685.. Whilst underground, visitors will be invited to tour a set route of the unusual rooms and spaces and document their feelings, sensations and experiences. The participants will be unaware of whether the infrasound is being generated or not. The research is the first of its kind to exclusively examine whether infrasound could be the cause of feelings associated with paranormal experiences or if such feelings truly are an inexplicable phenomena.

The levels of infrasound during the events will be controlled by an infrasound generator, which has been uniquely constructed by Steve Parsons. Infrasound is defined as acoustic energy with frequencies less than 20 Hertz (Hz), making it below the reach of human hearing. There are many sources of infrasound including man-made sources such as road traffic, aircraft and trains as well as natural sources including thunder, earthquakes and wind. In addition, during the week, the team will be conducting an infrasound survey of the close using state-of-the-art equipment calibrated to US military standards.

Commenting on the research events Dr Ciaran O’Keeffe said “Low frequency sound is legendary: from military weapons to the tiger’s roar and now to haunted houses. This experiment hopes to uncover some of the truth behind the legends.
Is sound the science behind hauntings?”

For the full line up of Ghost Fest events, please visit www.edinburghghostfest.co.uk (http://www.edinburghghostfest.co.uk/)
For more information on the work of Dr Ciaran O’Keeffe please visit www.theparapsychologist.com (http://www.theparapsychologist.com/) (mobile: 07984-954728, for more information on the work of Steve Parsons please visit www.parascience.org.uk (http://www.parascience.org.uk/) (07841-902994)

chillzero

14th May 2007, 02:29 PM

Oh great!
There are a bunch of us from Scotland meeting up in Edinburgh on 19th.

I just realised that I meant to ask here about anyone wishing to join us - but I forgot to start a thread. Details, if you are interessted:

http://forums.randi.org/showthread.php?t=80160

Dr B

14th May 2007, 03:57 PM

Commenting on the research events Dr Ciaran O’Keeffe said “Low frequency sound is legendary: from military weapons to the tiger’s roar and now to haunted houses.

Peer-reviewed references anyone?

Is sound the science behind hauntings?”
In short - no.

Is it double-blind? Participants may not know - but my hunch is the researchers will!!!!

JonDonnis

19th May 2007, 10:49 AM

I know Steve Parsons well, and he does have a genuine interest in studying infrasound and so on.

I personally am not convinced on infrasound, but I suppose if proven could explain a lot.

My main point of disagreement is that I have never had "a feeling" which is discribed as the result of infrasound.

That paranormal experience has always elluded me. And that is my problem.

For example I can stand in a pitch black cell at Bodmin Gaol, and i feel nothing, it doesn't bother me, yet others immediately before and after claim to feel uneasy, sense a presence and so on.

If infrasound is a possible explanation for similar such occruances, then why doesnt it affect me

Dr B

21st May 2007, 11:59 AM

I know him as well, and wish him well on his investigation. O0 But I cannot see any role for infrasound at all in these experiences. It is interesting that a recent critique of infrasound has gone ignored in their case for doing the study hhhmmmm.....

A reasonable case, even a tentative one, needs to be made for infrasound. Tandy never made a convincing case for it :-\

If you compare it to the mag field debate there are some parallels. However, the mag field effect has been replicated across different laboratories and under single-blinded (and some double-blinded) conditions. So although a mechanism is vague - there are sound demonstrations of a non-specific effect.

I guess the infrasound people might try to say that different people have differing susceptibilities to the sound - but again my hunch is this will be unclear.

I no longer think that magnetic fields, on there own can induce strange experience (as some have claimed). I think they interact with other psychological / contextual / situational factors. So the effects are subtle and non-specific - but can, in some circumstances produce striking experiences. However, my research is suggesting that this is rare.

Admin

21st May 2007, 12:26 PM

It is interesting that a recent critique of infrasound has gone ignored in their case for doing the study hhhmmmm....

I still haven't seen this article BTW.

Could you email me a copy?

Parascience

21st May 2007, 12:44 PM

Dr B

21st May 2007, 12:57 PM

The data are already in on EIFs - so maybe you need to read up some more. O0

Infrasound is everywhere - so the argument for it will need to get around that...

You are quite right that proper experiments will definately speak to it. By 'proper' I assume you mean double-blinded tests? If not, then the claim of 'proper' seems undermined?

Dr B

21st May 2007, 01:39 PM

I presume that you mean the JSPR paper!

Indeed I do. Seems a shame not to be fully comprehensive in ones motivation for investigation. I think the case for doing an investigation on infrasound is boosted by showing that there is controversy over the issue. I still note the lack of real citations for an effect of infrasound on perception (i.e., peer-reviewed journal articles)?

I think it has all the potential to be an excellent experiment and is definately what the field of infrasound study needs.O0 I look forward to the results. However, studies like this do need to be double-blind.

I am doing one such study at the moment with EIFs which is exactly that - double-blind.

Dr B

21st May 2007, 02:28 PM

I still haven't seen this article BTW.

Could you email me a copy?

John

Teek has a copy of the whole journal which i donated to the UKS library (the JSPR give authors a few copies - which is nice). Best ask Teek to pop it in the post to you O0

Parascience

21st May 2007, 02:38 PM

Indeed I do. Seems a shame not to be fully comprehensive in ones motivation for investigation. I think the case for doing an investigation on infrasound is boosted by showing that there is controversy over the issue. I still note the lack of real citations for an effect of infrasound on perception (i.e., peer-reviewed journal articles)?

I think it has all the potential to be an excellent experiment and is definately what the field of infrasound study needs.O0 I look forward to the results. However, studies like this do need to be double-blind.

I am doing one such study at the moment with EIFs which is exactly that - double-blind.

That's the trouble with being the first to conduct in-field studies on Infrasound perception - there are no convenient peer review articles at present. However, I am sure that in the near future we will rectify that anomaly. At that time we will welcome your comments and criticisms and will respond appropriately but it's rather a waste of both parties valuable time to debate what was merely a press release intended for a non-scientific audience as I am sure you will agree.

Admin

21st May 2007, 02:45 PM

Hi, Steve (I presume).

Make sure to keep us informed of your findings. O0

I'll certainly be interested to learn what you've found out.

John

Parascience

21st May 2007, 02:51 PM

Hi, Steve (I presume).

Make sure to keep us informed of your findings. O0

I'll certainly be interested to learn what you've found out.

John

Hi John,
Happy to - we just need to catch on on some sleep and as soon as the eyes are able to focus;) we will start crunching the numbers, hopefully won't be too long but we have lots of them to get through.

Steve

Dr B

22nd May 2007, 11:00 AM

That's the trouble with being the first to conduct in-field studies on Infrasound perception - there are no convenient peer review articles at present.

Sorry - you misunderstand. The press release and supporting blurb claims and hints that there are effects of infrasound. However, with the exception of the questionable work of tandy - this is not furnished with any peer-reviewed work (much is based on myth from what I can see). As such there is no case to be made on that score. Dont get me wrong - i think its a good thing to do the research you are proposing - but i would have built a different form of argument - one based on the existing confusion - rather than imply that there is evidence 'out there' and you are following promising research. This will also make it easier for you when a null effect occurs (as may well be the case).

You acknowledge in your comments above that there are no direct peer-reviewed experiments (there was project Haunt by French - which is in 'Cortex' in press) - but that is not the impression given in the information. Hence, I think it is misleading to say you are testing a theory - as you are not - you are testing an idea or a suggestion. So it is the context of the test I am addressing. O0 There has been a failure to get an effect from an experiment - it would be nice to know how you are going to get around the shortcomings of that pilot work. So, as I said previously, the supporting information could be more comprehensive and no less engaging.

However, I am sure that in the near future we will rectify that anomaly.

I am sure you will O0 - it looks interesting and I wish you well with it.

At that time we will welcome your comments and criticisms and will respond appropriately but it's rather a waste of both parties valuable time to debate what was merely a press release intended for a non-scientific audience as I am sure you will agree.

Debating has never been a waste of time and it is something most parapsychologists should do a lot more. While I agree a press release has to engage the imagination - it should never mislead the public. This is counter-productive in my opinion as all it serves to do is propogate the myth that there is something to infrasound (the present myth that is). All you had to do was mention that there is an argument over the role of infrasound - I cannot for the life of me see why that was such a problem for a press release. :-\

So Steve - is it going to be double-blind? Could you inform this scientific audience as to the generic protocol / methods?

Parascience

22nd May 2007, 11:47 AM

Sorry - you misunderstand. The press release and supporting blurb claims and hints that there are effects of infrasound. However, this is not furnished with any peer-reviewed work. The work of Tandy is cited - but not the critique and everything else is based on myth from what I can see. As such there is no case to be made on that score. Dont get me wrong - i think its a good thing to do the research you are proposing - but i would have built a different form of argument - one based on the existing confusion - rather than imply that there is evidence 'out there' and you are following promising research. This will also make it easier for you when a null effect occurs (as may well be the case).

You ackonwledge in your comments above that there are no peer-reviewed experiments (which I think is true) - but that is not the impression given in the information. Hence, I think it is misleading to say you are testing a theory - as you are not - you are testing an idea or a suggestion. So it is the context of the test I am addressing. O0

I am sure you will O0

Debating has never been a waste of time and it is something most parapsychologists should do a lot more. While I agree a press release has to engage the imagination - it should never mislead the public. This is counter-productive in my opinion. All you had to do was mention that there is an argument over the role of infrasound - I cannot for the life of me see why that was such a problem for a press release. :-\

So Steve - is it going to be double-blind? Could you inform this scientific audience as to the generic protocol / methods?

The press release is (was) meant purely to engage the media and public interest in the subject matter. I do not agree that it was misleading in any way. The reference to Military Weapons is based upon several well documented research programmes and peer reviewed papers i.e. "Accoustic Weapons - A Prospective Assessment: Sources, Propagation and effects of Strong Sound (Altmann, 1999, Cornell University). Tandy is of course cited as it was his original hypothesis that Infrasound may be implicated in some types of perceived paranormal experience and also as it was the aim of the experiment to test his idea that 18.9Hz was a critical frequency in the production of such experiences within certain individuals. The Press Release does clearly state within the opening line that we trying to discover whether Infrasound could be the real reason behind haunting experiences and so I fail to see how we can be accused of misleading. The skill in writing a Press Release is in encapsulating the information within a few brief lines as we know from experience that few journalists rarely read beyond the 1st paragraph let alone the entire page.

Dr B

22nd May 2007, 11:58 AM

The press release is (was) meant purely to engage the media and public interest in the subject matter. I do not agree that it was misleading in any way.

I did not say you were directly misleading the public - the context of the proposal is misleading because you are not doing the literature a full service. This does not require anything more than one or two clear statements.

The reference to Military Weapons is based upon several well documented research programmes and peer reviewed papers i.e. "Accoustic Weapons - A Prospective Assessment: Sources, Propagation and effects of Strong Sound (Altmann, 1999, Cornell University).

I was under the impression that Military testing involved high-amplitude low frequency sound - this is not infrasound? Do you have a reference where they used amplitudes less than 50-60dB? This was discussed in my critique. To qualify as infrasound it must not be audible and thus must be below 50-60db.

Tandy is of course cited as it was his original hypothesis that Infrasound may be implicated in some types of perceived paranormal experience and also as it was the aim of the experiment to test his idea that 18.9Hz was a critical frequency in the production of such experiences within certain individuals.

I know - but this has been challenged. This does not undermine the experiment you are proposing as it shows the need (more so) for your experiment. Your are just creating a mispreception that Tandy really did show what he claims he did. My critique shows why he did no such thing!

The Press Release does clearly state within the opening line that we trying to discover whether Infrasound could be the real reason behind haunting experiences and so I fail to see how we can be accused of misleading.

I have explained this above. If it were me, i would have cast it more as being directed at addressing the controversy in the debate. I think people like Gauld also criticised infrasound as well.....but cant quite remember.....:cheesy:.

The skill in writing a Press Release is in encapsulating the information within a few brief lines as we know from experience that few journalists rarely read beyond the 1st paragraph let alone the entire page.

There is no excuse for not casting the debate in its propoer context. Casting it as a much needed experiment - that would speak to a current controversy would have been a better way to go. The problem is people may remember the press release - but will never see the results - as such memory can be biased to think that you did actually find something. The language used is too positive to the infrasound theory, and its not well grounded in fact, - that is all i am saying.

Anyway, moving on, is it double-blind steve?????

Parascience

22nd May 2007, 02:12 PM

I was under the impression that Military testing involved high-amplitude low frequency sound - this is not infrasound? Do you have a reference where they used amplitudes less than 50-60dB? This was discussed in my critique. To qualify as infrasound it must not be audible and thus must be below 50-60db.

You are mistaken about how you are defining Infrasound here (and in your recent JSPR paper too) The defining feature of Infrasound is that is it is below the frequency range of normal human hearing - typically stated to be c.20Hz. "Frequencies down to a few Hz are audible at high enough levels, Sometimes, although Infrasound is audible, it is not recognised as sound and there is uncertainty over the detection mechanism" (Leventhall, Dr. G, 2003 - A Review of Published Research on Low Frequency Noise and it's Effects - Report for DEFRA). The figures you quote i.e 50-60dB are also potentially misleading as you do not make it clear if they are weighted values or direct ratios of Sound Pressure Level - if you mean the latter then the actual figures for inaudibility are much higher than you are quoting - for 18.5Hz for example the figure is in excess of 80dB SPL (Watanabe & Muller, 1990). Weighting as applied by many enviromental sound / noise meters is usually in the form of Type A and Type C and it has been known for several years that neither weighting can be used sucessfully for the measurement of frequencies below 30Hz. Your challenge of Vic's ideas and experiments may be valid and we are aware of a number of problems with his work - for example, One key problem with Vic Tandy's measurements is that he does not state what (if any) filter weighting he applied. In 'Something in the Cellar' he provides us with information that he found Infrasound at 18.9Hz and 38dB but if this is a weighted measurement then we know from measurements obtained at the same location (Coventry Tourist Information Cellar) last year, that the ambient infrasound measured was in excess of 70-80dB SPL. Vic was denied the opportunity to develop his hypothesis fully and to conduct the field measurements he needed to do and like other pioneers into new areas of study he was bound to make many mistakes - I am sure that you can look back over your early work with EIF's and spot some areas where improvements could have been made. We believe that the best and perhaps the only substantial way to really test Vic's ideas is to develop meaningful experiments and see what the results tell us. Another difficulty when it comes to speaking with any authority about Infrasound is that currently there is little or no data about the actual amounts of infrasound encountered within the environment - locations, haunted or otherwise simply have never been measured and we are currently engaged on a long term project funded by the SPR obtaining that information for a wide range of geographically and typologically diverse haunted and associated controls in order to go some way toward rectifying that situation. With that sort of information we will all be in a far better position to debate the Infrasound vs Paranormal Perception question.

With regard to your question about the methodology and if the experiment conducted at Mary Kings Close was Double-Blind, the short answer is NO it was not and for many good and practical reasons which we will discuss in the eventual paper. The praticalities of field-based experimentation do not always lend themselves to the 'perfect experiment' but we are confident that any issues arising from our methods will not seriously hinder our results.

Dr B

22nd May 2007, 02:37 PM

You are mistaken about how you are defining Infrasound here (and in your recent JSPR paper too)

No - I am not. The fudging of the terminology came after the distinctions in engineering, psychophysics, physics and for reasons of parsimony. If you can hear somthing - it is not infrasound - it is sound!!!!! Low-frequency sound is just that - low frequency sound (usually of high amplitude). This is not infrasound.

Infrasound, by definition, is none-audible. A more accurate physical description is Inaudible Air Vibration. You seem confused as to whether you are descibing the physical parameters, or the psychological ones (i.e., perception of sound). It is best to keep these ideas distinct. It is not possible to have a 'sound' below perceptual thresholds - as 'sound' is a perceptual construct. So the whole term 'infrasound' is confusing and a confusion many authors have added to. There is a real distinction here between low-frequency sound and infrasound. If you dont make that distinction you are making the same error as the other authors. Remember - in your case - psychology is important as you are dealing with human responses so it is more important for you to be clear on this. In my paper i introduced the term true-infrasound to help with these distinctions. You may find this useful.

The defining feature of Infrasound is that is it is below the frequency range of normal human hearing - typically stated to be c.20Hz.

No - frequency and amplitudes of hearing. Hence the need for the additonal 'infra' - otherwise its just low-frequency sound.

"Frequencies down to a few Hz are audible at high enough levels, Somtimes, although Infrasound is audible, it is not recognised as sound and there is uncertainty over the detection mechanism" (Leventhall, Dr. G, 2003 - A Review of Published Research on Low Frequency Noise and it's Effects - Report for DEFRA).

Of course they are audible at high amplitude levels - this is called....sound!

The figures you quote i.e 50-60dB are also potentially misleading as you do not make it clear if they are weighted values or direct ratios of Sound Pressure Level - if you mean the latter then the actual figures for inaudibility are much higher than you are quoting - for 18.5Hz for example the figure is in excess of 80dB SPL (Watanabe & Muller, 1990).

They are not misleading at all - though they are only a generic guide. Psychophysical experiments suggest these figures (note these experiments are based on perceptual discrimination thresholds using signal-detection theory). In fact, its worse than you suggest because there is a reasonable amount of between-person variability. Obviously you will have screened your participants and will have a sensitivity measure (something like a d-prime?) for each person. If not - then any positive results could be reactions to sound (for some people) and not true infrasound.

The figures can vary depending on context and whether sound is being presented with other competing stimuli as well. However, 50 - 60db is generally regarded as a generic minimum threshold for frequencies of around 20Hz. Though I expect this to be refined with proper experimentation.

Weighting as applied by many enviromental sound / noise meters is usually in the form of Type A and Type C and it has been known for several years that neither weighting can be used sucessfully for the measurement of frequencies below 30Hz.

Largely irrelevant for psychophysical studies of sound. Remember - d-prime is an individual measure of sensitivty and response bias.

Your challenge of Vic's ideas and experiments may be valid and we are aware of a number of problems with his work - for example, One key problem with Vic Tandy's measurements is that he does not state what (if any) filter weighting he applied.

I agree with your conclusion - but not for your reasons. You might want to think about the brain / psychology alittle more.

In 'Something in the Cellar' he provides us with information that he found Infrasound at 18.9Hz and 38dB but if this is a weighted measurement then we know from measurements obtained at the same location (Coventry Tourist Information Cellar) last year, that the ambient infrasound measured was in excess of 70-80dB SPL.

My hunch is if you are right - he would have mentioned it as he was somewhat unimpressed with the levels himself (38db) and openly acknowledges this fact (he struggles to make a case in his own paper). Therefore, I think your idea of 70-80db is not supported by the literature at all and is on shaky grounds. In fact - this would have generated a small sound at around 20Hz - as none was reported I think we can ignore the idea.

Vic was denied the opportunity to develop his hypothesis fully and to conduct the field measurements he needed to do and like other pioneers into new areas of study he was bound to make many mistakes - I am sure that you can look back over your early work with EIF's and spot some areas where improvements could have been made.

One can always spot improvements. However, not taking baselines and providing no measures at all in his first paper is a childs mistake. However, I share your general sentiment.

We believe that the best and perhaps the only substantial way to really test Vic's ideas is to develop meaningful experiments and see what the results tell us.

I agree in part. But those experiments will need to be double-blind and carried out with a good methodology - which i am sure you are working towards O0

Another difficulty when it comes to speaking with any authority about Infrasound is that currently there is little or no data about the actual amounts of infrasound is encountered within the environment - locations, haunted or otherwise simply have never been measured and we are currently engaged on a long term project funded by the SPR obtaining that information for a wide range of geographically and typologically diverse haunted and associated controls in order to go some way toward rectifying that situation.

Indeed - but it may be the case no figures exist because its not important for physical reasons. However, I share your view - much to do and well worth an investigation.

With that sort of information we will all be in a far better position to debate the Infrasound vs Paranormal Perception question.

We are in a good position now based on logic, prior failures (the direct attempts I am aware of are all failures) and the misunderstandings of infrasound (see my above comments).

With regard to your question about the methodology and if the experiment conducted at Mary Kings Close was Double-Blind, the short answer is NO it was not and for many good and practical reasons which we will discuss in the eventual paper.

Thats a shame. Maybe you need to think of a follow up that is double-blind. You see, not all debates are pointless!!!!

The praticalities of field-based experimentation do not always lend themselves to the 'perfect experiment' but we are confident that any issues arising from our methods will not seriously hinder our results.

I know it is difficult - but where direct manipulations of this sort are involved - it is essential they are double-blind. This will hinder the results to some extent. However, as a pilot study I am sure it will be interesting. O0

Dr B

22nd May 2007, 03:13 PM

My hunch is, that all those miltary references are based on high-amplitude low frequency sound and not true infrasound. As such they can be legitimately ignored in the case for true infrasound as they are not, either physically or perceptually, the same thing.

The real question is; what empirical demonstrations are there that true infrasound (less than 20Hz and less than 50-60db) has any effect on perception and can underlie anomalous reports. The answer is, as I said at the begining, none.

Now, while there is a case for looking at this more closely, my argument is, let us do this with a thorough understanding of what the current literature says first.

You could argue (as some would) - that as there is no a-priori evidence or reasons (no mechanisms / evidence) - it's a pointless exercise. However, I would say it is only pointless if it further contributes to, rather than resolves, the confusion. I am sure this will not have been the case and I look forward to reading the final paper. O0

Parascience

22nd May 2007, 03:20 PM

No - I am not. The fudging of the terminology came after the distinctions in engineering, psychophysics, physics and for reasons of parsimony. If you can hear somthing - its not infrasound - its sound!!!!!
Low-frequency sound is just that - low frequency sound (usually of high amplitude). This is not infrasound.

Infrasound is none-audible. A more accurate physical description is Inaudible Air Vibration. You seem confused as to whether you are descibing the physical parameters, or the psychological ones (i.e., perception of sound). It is best to keep these ideas distinct. It is not possible to have a 'sound' below perceptual threasholds - as 'sound' is a perceptual construct. So the whole term 'infrasound' is confusing and a confusion many authors have added to.

A confusion you are adding to by repeatedly stating that to qualify as Infrasound it must be inaudible - there are No definitions of Infrasound that state anything other than frequency is the defining factor - by your definition ALL inaudible sounds may be Infrasound and clearly they are not - Accoustitions refer to sub-audible or sub-sonic sound to make this distinction clear

Of course they are audible at high amplitude levels - this is called....sound!

Sound is accoustic energy that has tone / pitch. Below about 16Hz the human hearing loses the ability the detect tone and so this is more commonly referred to as Noise.

They are not misleading at all - though they are only a generic guide. Psychophysical experiments suggest these figures (note these experiments are based on perceptual discrimination threasholds using signal-detection theory). In fact, its worse than you suggest because there is a reasonable amount of betwee-person variability. Obviously you will have screened your participants and will have a sensitivity measure (something like a d-prime?) for each person.

The figures can vary depending on context and whether sound is being presented with other competing stimuli as well. However, 50 - 60db is generally regarded as a generic minimum threashold for frequencies of around 20Hz.

It is a common mistake to provide figures for sound level measurements without stating clearly what (if any) weighting has been applied to the data. It serves only to muddle the discussion as there can be large variations between the amount of measured sound (weighted) and the actual sound pressure levels present. This point has been acknowledged by Low Frequency and Vibration Researchers for many years.

My hunch is if you are right - he would have mentioned it as he was somewhat unimpressed with the levels himself (38db) and openly acknowledges this fact. Therefore, I think your idea of 70-80db is not supported by the literature at all and is on shaky grounds. Infact - this would have generated a small sound at around 20Hz - as none was reported I think we can ignore the idea.

It is well supported by literature - several studies have been conducted that have measured the environmental Infrasound i.e Von Gierke & Parker, (1976) Infrasound levels of between 70dB & 120dB SPL are commonly encountered within the environment. Vic was using a Bruel & Kjar type 2209 sound meter which has a frequency range pre-selector switch set in 1/3 octave bands. When the range of interest is selected the meter automatically zero's itself to one of a number of user selected frequency weighting scales. Thus if it were used as we suspect (from the makers instructions) on 16Hz range scale the meter would have zeroed itself to a 50dB 'C' weighting and only show the amount of accoustic energy above this level i.e 38dB C. As we do not know (and may never know) what settings Vic used it is highly likely that this simple error was made at the time. The figures I provided for the Coventry Cellar where made ny me during a visit in 2006 (actually the day before they demolished the Tourist Information Office) and are stated in terms of dB SPL. Although there is no direct conversion between dB SPL and either of the common weighting scales 'A' or 'C' as it is entirely dependent upon the ratio of sound and low frequency sound i.e below 100Hz I would not be surprised to see a similar measured value to Vic's 38dB if we had used an off the shelf sound level meter as he did.

Dr B

22nd May 2007, 03:44 PM

A confusion you are adding to by repeatedly stating that to qualify as Infrasound it must be inaudible

No - you are quite wrong here. You are taking a language of physics and engineering (one being refined as we speak) and applying it to perceptual levels. Sensation and perception are NOT the same thing and one needs to be clear how one quantifies it and how one describes that quantification. It is true that many others have generally described what you mention. However, I have challenged most via e-mail to explain this to me and a rather odd thing happens.

They agree with me - that applied to human responses the language and terminology is not sufficient. A lot of the definitions are being used by people only interested in the physics (i.e., the sensation). However, you, and all researchers interested in infrasound and perception are not just interested in that. Of course, one might want to argue = lets use both - which is fine - but it recognises that the current language does not work in a theory of brain / psychological responses. You must remain clear on whether you are describing the physics 'out there' or the perceptual response to them.

- there are No definitions of Infrasound that state anything other than frequency is the defining factor

Yes there are - mine!!! :cheesy: The reason db is not given is because of problems within the science due to generating and measuring the exact amount degrees of infrasound (at least in the early days).

- by your definition ALL inaudible sounds may be Infrasound and clearly they are not - Accoustitions refer to sub-audible or sub-sonic sound to make this distinction clear

No - sounds below the parameters set that are inaudible (not ones above these parameters and outside of the hearing response). Yes there are other terms out there - but infrasound itself was distinguished from low-frequency sound on the basis of infrasound being inaudible (but just). So I think you will find that all the terms can be used on a continuum of db. Infrasound is what you are interested in though - so use that term - but use it correctly. it refers to 'sound' that is just beyond the cusp of perception - not far beyond it.

Sound is accoustic energy that has tone / pitch. Below about 16Hz the human hearing loses the ability the detect tone and so this is more commonly referred to as Noise.

I would not use the term noise in this debate to descibe something which cannot be heard - unless it is within the context of neural noise or some other mechanism (i.e., metaphorically like 'visual noise'). Again, i see you are ignoring the psychology involved here.

It is a common mistake to provide figures for sound level measurements without stating clearly what (if any) weighting has been applied to the data. It serves only to muddle the discussion as there can be large variations between the amount of measured sound (weighted) and the actual sound pressure levels present. This point has been acknowledged by Low Frequency and Vibration Researchers for many years.

Yes - and its a common mistake to get confused over the sensation and perception distinction becasue many of these researchers are not psychologists or brain scientists - so its irrelevant to them.

It is well supported by literature - several studies have been conducted that have measured the environmental Infrasound i.e Von Gierke & Parker, (1976) Infrasound levels of between 70dB & 120dB SPL are commonly encountered within the environment.

This is not infrasound - its low frequency sound and often reported with discomfort especially at the higher levels (meaning it can be heard). You see - this is where the confusion comes from. Once it can be heard - it is not infrasound - it is sound (albeit weak sound).

Vic was using a Bruel & Kjar type 2209 sound meter which has a frequency range pre-selector switch set in 1/3 octave bands. When the range of interest is selected the meter automatically zero's itself to one of a number of user selected frequency weighting scales. Thus if it were used as we suspect (from the makers instructions) on 16Hz range scale the meter would have zeroed itself to a 50dB 'C' weighting and only show the amount of accoustic energy above this level i.e 38dB C. As we do not know (and may never know) what settings Vic used it is highly likely that this simple error was made at the time. The figures I provided for the Coventry Cellar where made ny me during a visit in 2006 (actually the day before they demolished the Tourist Information Office) and are stated in terms of dB SPL. Although there is no direct conversion between dB SPL and either of the common weighting scales 'A' or 'C' as it is entirely dependent upon the ration of sound and Infrasound i.e below 20Hz I would not be surprised to see a similar to Vic's 38dB if we had used an off the shelf sound level meter as he did.

This is all flawed by the fact that neither he, nor others, reported hearing any sounds - which they would have heard for 20Hz peaks at those amplitudes. I dont think the staff reported it either - from what i can tell in the literature. I think you are speculating here. Its fine to do so - but its a judgement call as to whether you are speculating too wildly.

Dr B

22nd May 2007, 04:01 PM

Steve

Just to be clear - when I talk about infrasound - I mean what is known as true infrasound or real infrasound. I did make this very clear earlier and in my paper - but I have not repeated it everytime (this may have lead to some confusion).

The reason true-infrasound is more crucial for Tandy's claims, is because neither he nor anyone else reported hearing anything at the time the measurements were taken. So for his theory to be true - we need an instance of true-infrasound (not audible) affecting perception.

Anything else is not testing his theory, as he proposed it. Of course, higher levels may have effects, but my hunch is once they become audible - its a whole different ball game.

Parascience

22nd May 2007, 04:08 PM

No - you are quite wrong here. You are taking a language of physics and engineering (one being refined as we speak) and applying it to perceptual levels. Sensation and perception are NOT the same thing and one needs to be clear how one quantifies it and how one describes that quantification. It is true that many others have generally described what you mention. However, I have challenged most via e-mail to explain this to me and a rather odd thing happens.

They agree with me - that applied to human responses the language and terminology is not sufficient. A lot of the definitions are being used by people only interested in the physics (i.e., the sensation). However, you, and all researchers interested in infrasound and perception are not just interested in that. Of course, one might want to argue = lets use both - which is fine - but it recognises that the current language does not work in a theory of brain / psychological responses. You must remain clear on whether you are describing the physics 'out there' or the perceptual response to them.

You are making an assumption that sound perception is purely a function of hearing and there are a number of studies that show that air vibrations (sound / noise) is also detected and therefore maybe perceived via other mechanisms i.e. bone conduction but also that the ears may actually be involved too.

Yes there are - mine!!! :cheesy: The reason db is not given is because of problems within the science due to generating and measuring the exact amount degrees of infrasound (at least in the early days).

There are no problems within science with either the generation or measurement of Infrasound, the only problems occur when people choose to disregard the standard accepted definitions and measurement ratios in favour of something they decide suites their argument better. Your suggested term IAV is another example of this approach and does nothing to help remove the confusion that exists in the minds of many people.

I would not use the term noise in this debate to descibe something which cannot be heard - unless it is within the context of neural noise or some other mechanism (i.e., metaphorically like 'visual noise'). Again, i see you are ignoring the psychology involved here.

You may choose not to use the term but it is the accepted definition of sound that is either annoying or has no discernable tone as is the case with Infrasound.

This is not infrasound - its low frequency sound and often reported with discomfort especially at the higher levels (meaning it can be heard). You see - this is where the confusion comes from. Once it can be heard - it is not infrasound - it is sound (albeit weak sound).

Simply repeating a wrong definition won't help anyone

This is all flawed by the fact that neither he, nor others, reported hearing any sounds - which they would have heard for 20Hz peaks at those amplitudes. I dont think the staff reported it either - from what i can tell in the literature. I think you are speculating here. Its fine to do so - but its a judgement call as to whether you are speaculating too wildly.

Your argument is flawed by your lack of understanding about the physics and nature of sound production, absorbtion and dispersion - it is perfectly possible and indeed commonly found by measurement that the amplitude of one sound does not mean that sound of adjacent frequencies is of a similar amplitude. Thus is perfectly possible to have a high amplitude sound of say 18.9Hz that an observer is not aware of and no significant sound at 20Hz.

Parascience

22nd May 2007, 04:15 PM

Of course, higher levels may have effects, but my hunch is once they become audible - its a whole different ball game.

I find much to agree on here - although we disagree on some aspects of perception - even if it is audible by conventional i.e. aural hearing, the percipient may not be aware the sound stimulation is present as conventional sound - additionally they may also be being affected by distinct and indistict physical effects too. It is how they ultimately interpret and report these effects that we need to consider.

Parascience

22nd May 2007, 04:30 PM

Dr B

22nd May 2007, 04:38 PM

You are making an assumption that sound perception is purely a function of hearing and there are a number of studies that show that air vibrations (sound / noise) is also detected and therefore maybe perceived via other mechanisms i.e. bone conduction but also that the ears may actually be involved too.

Totally untrue. These other mechanisms only come into play at higher amplitudes - you keep making that mistake. You keep recruiting the high-amplitude stuff to make points about the low-amplitude stuff. Fortunately, I spot this O0

I do not make the assumption you think I do - I just point out where your argument is flawed and inaccurate.

There are no problems within science with either the generation or measurement of Infrasound, the only problems occur when people choose to disregard the standard accepted definitions and measurement ratios in favour of something they decide suites their argument better. Your suggested term IAV is another example of this approach and does nothing to help remove the confusion that exists in the minds of many people.

Rubbish. It removes a perceptual component (the term sound) from the physical component (air vibration) and as such adds great clarity - at least to psychologists. Again, you ignore this distinction.

True-infrasound is inaudible air vibration. Once you hear it....its sound (as far as the brain is concerned)

You may choose not to use the term but it is the accepted definition of sound that is either annoying or has no discernable tone as is the case with Infrasound.

Wrong again. see this link for one example. You dont need to read further than the first few sentences of the abstract (the second sentence is very interesting) - something about infrasound being inaudible....::) http://adsabs.harvard.edu/abs/2003EAEJA.....6351E

Simply repeating a wrong definition won't help anyone

No steve, it doesn't help those who dont listen. You are quite right of course there is great confusion over infrasound - you have displayed much of this here.

Your argument is flawed by your lack of understanding about the physics and nature of sound production, absorbtion and dispersion - it is perfectly possible and indeed commonly found by measurement that the amplitude of one sound does not mean that sound of adjacent frequencies is of a similar amplitude. Thus is perfectly possible to have a high amplitude sound of say 18.9Hz that an observer is not aware of and no significant sound at 20Hz.

Steve - you are still not paying any attention to the psychology / brain response aspect of your argument. I see no consideration for psychological aspects in your case at all. I am not a physicist - but then - nor are you. I think you place too much emphasis on the literature you read as opposed to try to clear matters up by addressing issues in a clear manner.

Dr B

22nd May 2007, 04:42 PM

It may be a good point within the debate to explain that the Experiment as designed was originally set-up as a Double-Blind experiment but it was quickly apparent that the experimenters themselves were being affected by and thus were able to determine when the Infrasound generator was On or Off. For this reason, we were unable within the confines of the location and the need to maintain a public access experiment for more than 500 people to continue the experiment as a true Double-Blind experiment.

Fair point, and as I said earlier, simply means your study makes for a nice pilot study - but one which should be followed up. O0

I know double-blind is hard - god knows i have done enough to know. It is difficult and costly, but if and when ever possible it should be done with these types of experiments.

Dr B

22nd May 2007, 04:47 PM

Steve

The main reason you need to be very clear on whether you used true infrasound or not is because the brain may well respond differently under both circumstances.

In other words - if true infrasound has an effect - which is distinct from sound it would be important to understand it. However, if you have used low-frequnecy sound to generate the effects (with non-too-high amplitudes) - the response is still going to be the same - sound.

This does not prove anything at all. True infrasound may or may not have a distinct mechanism of interaction with the brain - this would be crucial to know if you want to test if Tandy is right.

Dr B

22nd May 2007, 04:52 PM

My hunch is that because you dont like my use of the terms above (which the engineers and experts I have spoken to all accept in the context of the studies) - you did not use true-infrasound.

So we may have a study that is not double-blind and did not use true-infrasound? Not sure how this speaks to the infrasound theory of Tandy.

Another thing - you need to be clear whether you are testing Vic's idea or your version / extension of it. As vic never reported hearing sounds in any of his cases - this suggests a true-infrasound approach.

However, if you are interested in low-frequency sound effects - then fine (but this is not what Tandy proposed and we need to be clear on that). I think both would be fascinating - but they are not the same thing.O0 Again, it is a case for clarity.

Parascience

22nd May 2007, 05:03 PM

Totally untrue. These other mechanisms only come into play at higher amplitudes - you keep making that mistake. You keep recruiting th high-amplitude stuff to make points about the low-amplitude stuff. Fortunately, I spot this O0

So in that case we do not perceive vibrations then...such as from passing heavy traffic, thunder or Earthquakes unless they are loud enough to hear?

True-infrasound is inaudible air vibration. Once you hear it....its sound (as far as the brain is concerned)

Infrasound is sound / noise below the range of normal human hearing - you are just fudging the issue - I and many other people have 'Heard' Infrasound as I would wager have you. All it needs is sufficient amplitude. I am starting to sound like a broken record - I could bore you with very many definitions of Infrasound to make the point that it is only defined by Frequency.

Wrong again. see this link for one example. You dont need to read further than the first few sentences of the abstract (the second sentence is very interesting) - something about infrasound being inaudible....::) http://adsabs.harvard.edu/abs/2003EAEJA.....6351E

You have managed to find a definition that actually mentions Infrasound is Inaudible (there are several others) but it doesn't alter the fact that Infrasound is defined by Frequency alone and NOT amplitude, which is the point you seem to keep overlooking.

No steve, it doesnt help those who dont listen. You are quite right of course there is great confusion over infrasound - you have displayed much of this here.

Change my name for yours here I think

I am not a physicist - but then - nor are you

You're right I am not a Physicist but all my academic qualifications (to degree level) and training are in the measurement and understanding of Physical variables which is what we are dealing with here. I'm well within my area of competance and understanding here as I am sure that my Ph.D research will demonstrate in the fullness of time.

Dr B

22nd May 2007, 05:26 PM

So in that case we do not perceive vibrations then...such as from passing heavy traffic, thunder or Earthquakes unless they are loud enough to hear?

Why would you arrive at that conclusion? I never said that at all. Again i think you need to concentrate on the psychology of what I am saying a little more O0

Infrasound is sound / noise below the range of normal human hearing - you are just fudging the issue

You mean inaudible? :cheesy:;D

- I and many other people have 'Heard' Infrasound as I would wager have you. All it needs is sufficient amplitude. I am starting to sound like a broken record - I could bore you with very many definitions of Infrasound to make the point that it is only defined by Frequency.

No - what you have failed to grasp is infrasound is a frequnecy range (the response of the ear rolls off and is not absolute) some of this 'range' is above hearing threshold but mainly because it does not make any physical sense to have a major cut off here. However, true infrasound is inaudible and as such, must be of low frequency (say <20hz) and of sufficiently low amplitude not to be heard as sound (say 50-60db for arguments sake). For our purposes it is important to have a marker between sound that is clearly heard as sound and vibration that is not experienced in the same way.

Every expert I have ever spoken to about this - hates the term 'infrasound' - when i ask why (even though i know) - they say it is because of the use of 'sound' in the title - all infrasound is air vibration but not all air vibration is infrasound. They claim it generates confusion (and clearly it does) for all the reasons we have discussed. Your claims about frequency alone are dated and based on estimates using average natural sound levels.

I believe there is a case for clarity - that is all. When you report your study you will need to be clear whether you used true-infrasound or low-frequency sound (I suspect the latter).

You have managed to find a definition that actually mentions Infrasound is Inaudible (there are several others) but it doesn't alter the fact that Infrasound is defined by Frequency alone and NOT amplitude, which is the point you seem to keep overlooking.

Nop - i have loads of references and all point to to covariation of frequency and amplitude. It is ridiculous to talk of sound without its associated energy - all infrasound can be made audible with sufficient power.

I'm well within my area of competance and understanding here as I am sure that my Ph.D research will demonstrate in the fullness of time.

I wish you well with it and i know you will take on board what has been discussed here O0

Parascience

22nd May 2007, 06:58 PM

all infrasound is air vibration but not all air vibration is infrasound.

Agreed - above 20Hz (ish) it's Sound and above 20kHz (ish) it's Ultrasound.

The rest we can just agree to disagree about for the time being at least :smiley:

median

23rd May 2007, 08:02 AM

Nop - i have loads of references and all point to to covariation of frequency and amplitude. It is ridiculous to talk of sound without its associated energy - all infrasound can be made audible with sufficient power.

Quick question.

If infrasound is categorised as being below a certain frequency range but on increasing the amplitude it was heard, would the sound actually become 'audible' using the proper auditory channels or rather would it be a consequence of vibration being transmitted through the body and impingeing on the bones of the ear? Would it be interpretted as more of a feeling than a sound?
Is the term audible the right one to use in this context?

Cuddles

23rd May 2007, 10:32 AM

Parascience

23rd May 2007, 11:06 AM

Parascience, the problem here seem to be that you are arguing definitions for the sake of the definition itself and not actually paying attention to the physics behind it. I think both of you, and everyone else, agree that the common usage of "infrasound" simply means a frequency below the normal human hearing threshold of about 20Hz. However, as Dr. B has pointed out several times, this definition is completely meaningless, especially from a scientific point of view.

Definitions form an important part of science and they are worth fighting for - if we all decided to force a new definition into existence just to suite our argument we would soon dissolve into chaos. Infrasound is a commonly accepted term and has an accepted definition which we need to maintain - it is not therefore meaningless, especially from a scientifc point of view.

and your attempts to force some kind of difference between sound above and below 20Hz are just utterly meaningless.

Where have I said there is any difference between sounds above and below 20Hz - in terms of the Physics of sound there is none but what I am trying to get across is that accoustic energy below 20Hz (ish) is defined as Infrasound regardless of whether of not it can be heard

The only way it can possibly make any sense to discuss infrasound and human perception is by defining infrasound to be air vibrations that are inaudible.

Don't tell me - tell the Accoustic Scientists, Military Scientists, Physicists, Academics etc who have been happily using the definition for years - if they are wrong then they need to be informed. I'm just using the accepted standard definition and if I am wrong blame them.

You must use infrasound that is inaudible to humans, regardless of frequency,

So by what you have just written then all sound (regardless of Frequency) that we cannot hear is Infrasound - wish I had known that before I developed the system - I could have done the whole thing using an iPod and a couple of wallkman speakers and generated any old frequency I liked (2kHz is a nice easy one to make) provided I simply kept the volume turned down low enough to ensure that it could not be heard.

I surrender to your obviously greater understanding of the Laws and Definitions of Physics than my own - I shall go and watch all the back episodes of Brainiac to try and brush-up on my knowledge - until then, Please accept my profound apologies for troubling you.

Admin

23rd May 2007, 01:50 PM

I think the important point is that whatever parameters were used for the infrasound in this experiment (frequency, intensity, etc.) they're clearly presented - which I'm sure they will be.

I'm looking forward to seeing the hypothesis tested and whether the statistical data supports it or not.

Also, whether any unexpected results came in which could lead to further hypotheses being developed.

I suspect that it's impossible to do an experiment that cannot be criticised in any way, but let's look at it within its limitations (which I'm sure the authors will acknowledge) and see what it tells us. O0

Dr B

23rd May 2007, 08:11 PM

Definitions form an important part of science and they are worth fighting for

Not if they are no longer sufficient (and it is unlikely they ever were). You see, i keep returning to the same point - 'sound' is a perceptual definition. If you think about it - inaudible infrasound is a misnomer. Sound that cannot be heard is air vibration. I have been saying this all along O0

- if we all decided to force a new definition into existence just to suite our argument we would soon dissolve into chaos.

Incorrect - if you make a reasoned case illustrating why certain terminology does not work in new circumstances - then you have made a case for the new terminology. This was discussed in the paper.

Remember the example steve? If a tree falls in the woods, and no one is there to see / hear it does it make a sound??????

Answer - no!!!!! Why do you think that is?

Infrasound is a commonly accepted term and has an accepted definition which we need to maintain - it is not therefore meaningless, especially from a scientifc point of view.

Totally incorrect - it is common but far from being accepted - as i said above, everyone i talk to (professionals) hates the term. In addition, in the context of these experiments the term is meaningless. Now, you could use the term "true-infrasound" but this is equivalent to inaudible air vibration - and the latter is more explanatory and accurate.

We do not need to maintain a term which is worthless and confusing. All sound is vibration, but not all vibration is sound. You are missing an opportunity for clarity here - which was started by myself and maurice.

Where have I said there is any difference between sounds above and below 20Hz - in terms of the Physics of sound there is none but what I am trying to get across is that accoustic energy below 20Hz (ish) is defined as Infrasound regardless of whether of not it can be heard

Totally wrong - true infrasound is inaudible. Remember we are not just talking about the physics of sound (though that is important). You are using a psychological term 'sound' to descibe a physical entity - this is misleading.

Don't tell me - tell the Accoustic Scientists, Military Scientists, Physicists, Academics etc who have been happily using the definition for years - if they are wrong then they need to be informed. I'm just using the accepted standard definition and if I am wrong blame them.

Steve, you are making a logical fallacy here - known as ad-populum. They are wrong (in this context) and note - none of them are psychologists. They use the term because its easy for their audience - however, we are talking about biophysics and so this is an important difference and the terms breakdown.

So by what you have just written then all sound (regardless of Frequency) that we cannot hear is Infrasound - wish I had known that before I developed the system

Cuddles can answer well enough....but i answered this posts ago - infrasound is a crude term for low-frequency sound.

I surrender to your obviously greater understanding of the Laws and Definitions of Physics than my own - I shall go and watch all the back episodes of Brainiac to try and brush-up on my knowledge - until then, Please accept my profound apologies for troubling you.

No need to be filpant steve, but some of the people you have been talking to are engineers and have backgrounds in physics as well. If they share my confusion, and provide good reasons for doing so - maybe, just maybe, we are right? ::)

Cuddles

24th May 2007, 10:21 AM

Definitions form an important part of science and they are worth fighting for - if we all decided to force a new definition into existence just to suite our argument we would soon dissolve into chaos. Infrasound is a commonly accepted term and has an accepted definition which we need to maintain - it is not therefore meaningless, especially from a scientifc point of view.

This just reinforces my point. You are arguing simply for the sake of the definition and not for any practical reason. Yes, definitions form an important part of science. This means it is very important that you use the correct definition. You are not. You are attempting to find an effect caused by inaudible "sound", but you include sound that is audible. This just makes no sense at all.

Where have I said there is any difference between sounds above and below 20Hz - in terms of the Physics of sound there is none but what I am trying to get across is that accoustic energy below 20Hz (ish) is defined as Infrasound regardless of whether of not it can be heard

When you define infrasound as all sound under 20Hz and try to study it as a distinct phenomenon. Since some can be heard and some can't it is very obvious that such a definition cannot be useful.

Don't tell me - tell the Accoustic Scientists, Military Scientists, Physicists, Academics etc who have been happily using the definition for years - if they are wrong then they need to be informed. I'm just using the accepted standard definition and if I am wrong blame them.

Perhaps before making glib statements like this you should actually check who you are talking to first. Iam one of those physicists. I don't need to be informed about this, I already know. It is you who needs to be informed, and I am kind enough to do so. It's no use appealing to authority when the authority is sitting right in front of you. What you don't seem to understand is that different definitions are used in different context. The definition you use makes sense in terms of sound production and propagation. It makes no sense at all in terms of human perception.

So by what you have just written then all sound (regardless of Frequency) that we cannot hear is Infrasound - wish I had known that before I developed the system - I could have done the whole thing using an iPod and a couple of wallkman speakers and generated any old frequency I liked (2kHz is a nice easy one to make) provided I simply kept the volume turned down low enough to ensure that it could not be heard.

Under some circumstances this definition could make sense. However, since infrasound generally refers specifically to low frequency sound it is not a very common definition. What is a common definition is low frequency sound below the threshold of human hearing. The "low frequency" part allows some ambiguity. The "below the threshold of human hearing" part doesn't. Unfortunately it is the unambiguous part you are ignoring.

I surrender to your obviously greater understanding of the Laws and Definitions of Physics than my own - I shall go and watch all the back episodes of Brainiac to try and brush-up on my knowledge - until then, Please accept my profound apologies for troubling you.

Apology accepted. However, instead of watching Braniac why don't you instead listen to what an actual physicist is telling you? Failing that, try to just use some common sense. If you are trying studying the effects of low frequency sound via channels other than ordinary hearing, using audible sound just does not make sense.

Dr B

24th May 2007, 12:00 PM

Quick question.

If infrasound is categorised as being below a certain frequency range but on increasing the amplitude it was heard, would the sound actually become 'audible' using the proper auditory channels or rather would it be a consequence of vibration being transmitted through the body and impingeing on the bones of the ear? Would it be interpretted as more of a feeling than a sound?
Is the term audible the right one to use in this context?

This lies at the crux of the problem. It is clear that as a term, infrasound, is breaking down in these contexts. I have suggested either using the distinction 'true-infraound' (which i still don't like) or Inaudible Air Vibration (IAV - which i much prefer) in my paper and above in this discussion.

As amplitude is increased the sound would be heard - as all low frequencies can be heard with sufficient amplitude. Now, could weak sound be misattributed as something else? - indeed yes it could - but it would be using much of the same neural apparatus in that process and the only difference would be high-level attributional processes in the brain. This would also vary from person to person.

The real question is whether vibration - at sub-threshold intensities -engages with similar or distinct mechanisms. The problem is - all studies I am aware of that claim to investigate infarasound actually use high-energy low-frequency audible sound. So this is not true-infrasound and as such has nothing to say on the matter. As such we cannot really investigate any distinct mechanism that is separate from sound perception. This has been totally missed by the community (and steve) - but was covered in the paper.

Chris French did Project haunt (a pilot study) which had people in a chamber being exposed to infrasound (versus no infrrasound) - which I think was sub-threshold (though I would have to check with him about that). There were no effects of infrasound. However, that was just a pilot and much improvement is needed.

So, does air vibration, at such weak db have the capacity to vibrate bones etc and become recruited into percpetion? This is the question that infrasound research should be addressing - but my hunch is - at such weak db - the answer is no.

The chances are any effects to be had will be at audible levels - but this may not implicate a separate biophysical mechanism.

Sound can be experienced as vibration if the sound is high-amplitude but the person has their hearing covered. But again - this is at high amplitude (the vestibular system is a likely candidate). The brain does not want to be distracted by weak db signals and so has developed methods for filtering them out.

One could look at auditory evoked potentials (via EEG) at sub-threshold intensities to see if the potential for a response is there at the cortical level (still some issues though) - but i dont want to give too many of my ideas away here......especially when you think about who could be watching ;D

Dr B

24th May 2007, 01:18 PM

While I would disagree with some of the points and statements of Leventhall, this concluding statement is interesting in light of the above discussion. Seems he agrees with me (and Cuddles) in the sense that the term infrasound is not that useful and is confusing.

“Infrasound is just a continuation of audible sound into a region where the hearing threshold rises as the frequency reduces……snip….. Consequently, it is suggested that, in scientific discourse related to human perception, the term ‘‘infrasound’’ is avoided and replaced by ‘‘low-frequency noise’’ or ‘‘low-frequency sound’’, with an indication of the frequency range under consideration. Infrasound should be reserved for investigations of very low-frequency atmospheric sounds, of natural or man-made origin, which is a well-established discipline”. Leventhall (2007)

O0

However, for our purposes here - Inaudiable air vibration is more accurate.

Parascience

24th May 2007, 02:00 PM

This just reinforces my point. You are arguing simply for the sake of the definition and not for any practical reason. Yes, definitions form an important part of science. This means it is very important that you use the correct definition.

I wholeheartedly agree so let's stick to the accepted definition that Infrasound is all acoustic oscillatory energy below a frequency of 20Hz.

You are not. You are attempting to find an effect caused by inaudible "sound", but you include sound that is audible. This just makes no sense at all.

No, we are attempting to find an effect caused by Infrasound and as we have never stated the Sound Pressure Level that was used in our experiment your assumption that we have included sound that is audible is what makes no sense at all. For the record, our Infrasound generator was producing an SPL of between 60dB SPL and 90dB SPL within the experimental areas - thus in terms of 'normal' human hearing was below the auditory threshold.

When you define infrasound as all sound under 20Hz and try to study it as a distinct phenomenon. Since some can be heard and some can't it is very obvious that such a definition cannot be useful.

I don't define Infrasound as all sound below 20Hz - I am using the accepted terminology for sake of clarity. For Example:

"Physics considers sound to be elastic media oscillations propogating as sound waves in gaseous, liquid and solid media. Sound osscilations are theoretically in the frequency range of Zero to Infinity. Depending upon the oscillation frequency, the sound oscillations are subdivided into into Infrasound, accoustic oscillations and Ultrasound (from the Latin terms of 'Infra' {under}, 'Ultra' {further, above} and the Greek term 'Akustikos' {related to hearing}." State Research Centre - Institute of Biophysics, Russian Federation, Research Report of Project 2361p.

"According to the adopted classifications, Infrasound is defined as sound oscillations of frequencies below 20Hz (some researchers sometimes note an upper limit of 16Hz). The adopted subdivision is determined by the peculiarities of the human hearing apparatus perceptiveness of the specific frequency range only. Lower Infrasound frequency is not specified; at present it is investigated to 0.001Hz i.e. Infrasound range covers ~15 Octaves." USAF Research Laboratory Technical Report 20040625 090

Sound oscillations are wave energy. A wave is characterised using the two parameters of Frequency and Amplitude. The basic quantative feature of the sound is the Sound Pressure Level. The measurement unit of sound pressure is Pascal (1Pa = 1 N/m2). To ease measurement, the logarithmic scale is used. 0 (Zero) dB SPL being the threshold magnitude of the average value of the sound pressure corresponding approximately to the hearing threshold of a 1kHz tone.

Perhaps before making glib statements like this you should actually check who you are talking to first. I am one of those physicists. I don't need to be informed about this, I already know.

I'm suprised that as a Physicist you are allowing Dr.B to use such a nonspecific definition as 'IAV' This term does not provide any information about the Frequency or Amplitude of the sound wave being either measured or produced. It is vague and unhelpful to any meaningful research. If he really wanted to find an abbreviation to avoid the use of the definition Infrasound then as a Physicist why didn't you suggest the already commonly used abbreviation 'LFAO' - Low Frequency Acoustic Oscillation as it least we would then know if he was referring to sound that has a Frequency of above or below 20Hz, which I am assuming he means.

Under some circumstances this definition could make sense.

So now a Physicist is saying that Infrasound can be re-defined as inaudible sound regardless of frequency:cheesy:

The "below the threshold of human hearing" part doesn't. Unfortunately it is the unambiguous part you are ignoring.

The concept of 'audibility' is meaningless in the Infrasound region. Sufficient evidence has accumulated to demonstrate that acoustic stimuli with frequencies as low as 1Hz can not only be heard but can also be described in terms of loudness refelcting differences in human hearing thresholds. Furthermore, it has been suggested that a very low frequencies human detection does not occur through hearing in the normal sense. Rather, detection results from non-linearities of conduction in the middle and inner ear which generate harmonic distortions in the higher, more easily audible frequency range. It is also critical to consider to consider waves which are detected through skeletal bones, the ear, harmonics, tactile sensations or resonance within the body organs. Detection raises the possibilty of subjective reactions and may also contribute in complex ways to effects - Physiological and Psychological.

Determination of any possible effects of Infrasound exposure must consider field data. Real occurences of Infrasound will often include considerable energy above and below 20Hz.

Apology accepted. However, instead of watching Braniac why don't you instead listen to what an actual physicist is telling you? Failing that, try to just use some common sense. If you are trying studying the effects of low frequency sound via channels other than ordinary hearing, using audible sound just does not make sense.

I gave up watching Brainiac as it was too difficult for me to understand - so I went and played with my Infrasound generating and Infrasound Measuring Equipment instead which I used my common sense to design and build

Dr B

24th May 2007, 02:18 PM

I wholeheartedly agree so let's stick to the accepted definition that Infrasound is all acoustic oscillatory energy below a frequency of 20Hz.

No - it doesnt work in this context and thats what you dont understand. You have never understood this at any point in this discussion.

No, we are attempting to find an effect caused by Infrasound and as we have never stated the Sound Pressure Level that was used in our experiment your assumption that we have included sound that is audible is what makes no sense at all. For the record, our Infrasound generator was producing an SPL of between 60dB SPL and 90dB SPL within the experimental areas - thus in terms of 'normal' human hearing was below the auditory threshold.

I am not sure I agree with your idea that these energy levels would be inaudible....but i need to know more before I can comment. I look forward to the paper.

I don't define Infrasound as all sound below 20Hz - I am using the accepted terminology for sake of clarity. For Example:

"Physics considers sound to be elastic media oscillations propogating as sound waves in gaseous, liquid and solid media. Sound osscilations are theoretically in the frequency range of Zero to Infinity. Depending upon the oscillation frequency, the sound oscillations are subdivided into into Infrasound, accoustic oscillations and Ultrasound (from the Latin terms of 'Infra' {under}, 'Ultra' {further, above} and the Greek term 'Akustikos' {related to hearing}." State Research Centre - Institute of Biophysics, Russian Federation, Research Report of Project 2361p.

What you dont understand is this terminology does not work in the context of sensation and perception.

"According to the adopted classifications, Infrasound is defined as sound oscillations of frequencies below 20Hz (some researchers sometimes note an upper limit of 16Hz). The adopted subdivision is determined by the peculiarities of the human hearing apparatus perceptiveness of the specific frequency range only. Lower Infrasound frequency is not specified; at present it is investigated to 0.001Hz i.e. Infrasound range covers ~15 Octaves." USAF Research Laboratory Technical Report 20040625 090

Irrelevant and flawed for the reasons (and see the papers given as well) already given. You are still ignoring sensation and perception.

I'm suprised that as a Physicist you are allowing Dr.B to use such a nonspecific definition as 'IAV' This term does not provide any information about the Frequency or Amplitude of the sound wave being either measured or produced.

True - but the idea is you provide that information in additon. But what you are still failing to spot is IAV, by definition, is not audible as so, as a perceptual construct, it is useful. Your confused still over the fundamentals of this approach. True infrasound is better described as IAV. Steve - the term 'infrasound' gives no information, and none of your quotes above do either - so your argument falls down (again).

It is vague and unhelpful to any meaningful research.

Untrue - for all the reasons already given. Steve, what actually is your background in Psychology and Neurophysiology?

If he really wanted to find an abbreviation to avoid the use of the definition Infrasound then as a Physicist why didn't you suggest the already commonly used abbreviation 'LFAO' - Low Frequency Acoustic Oscillation as it least we would then know if he was referring to sound that has a Frequency of above or below 20Hz, which I am assuming he means.

Where is the perceptual element in these? You have just made my point for me.

The concept of 'audibility' is meaningless in the Infrasound region.

This is a new claim from you - and its totally wrong. It is crucial, in this context.

Sufficient evidence has accumulated to demonstrate that acoustic stimuli with frequencies as low as 1Hz can not only be heard but can also be described in terms of loudness refelcting differences in human hearing thresholds.

Not enitrely true - the studies i am aware of use high amplitudes so it defeats your argument. They also use non-competitive sound presentations - hardly ecologically valid.

Furthermore, it has been suggested that a very low frequencies human detection does not occur through hearing in the normal sense. Rather, detection results from non-linearities of conduction in the middle and inner ear which generate harmonic distortions in the higher, more easily audible frequency range.

Very true - but only at higher db and when the sound is audible. Some exceptions are with studies using deaf people - no audible sound - but vibration is felt (but again at high db only).

Detection raises the possibilty of subjective reactions and may also contribute in complex ways to effects - Physiological and Psychological.

But you have not made the case for detection at low, none audible, db?

Parascience

24th May 2007, 02:19 PM

However, for our purposes here - Inaudiable air vibration is more accurate.

No it isn't as it fails to specify the Frequency or Amplitude of the signal source - you only prefer it because you made it up. Like your previous abbreviation EIF which also failed to contain information relating to the source signal frequency and amplitude. There is an accepted term that you could have used - LFAO which at least indicates that we are dealing with Low Frequency sound waves. You could even have argued for the use of LFIAV's which would have been much better.

Dr B

24th May 2007, 02:30 PM

No it isn't as it fails to specify the Frequency or Amplitude of the signal source - you only prefer it because you made it up. Like your previous abbreviation EIF which also failed to contain information relating to the source signal frequency and amplitude. There is an accepted term that you could have used - LFAO which at least indicates that we are dealing with Low Frequency sound waves. You could even have argued for the use of LFIAV's which would have been much better.

Steve

aaahh now it all becomes clear O0 I know the real reason you dont like this these terms and you have just shown why. O0 It has nothing to do with the underlying science at all, does it?

IAV states clearly that the 'sound' must be inaudible to count as IAV. This still leaves a range of frequencies and amplitudes - but a very restricted one. Using "infrasound" and then claiming err well it can be heard and can be silent and can be this....that...or the other..." is where the real confusion is.

There are many terms you can use - i note you ignored LFN (low-frequenyc noise) and even LFIN (low-frequency inaudible noise) - which is one only coined this year in the field. O0

Just use terms properly in the right context - that is all.

Dr. C

24th May 2007, 02:38 PM

Parascience

24th May 2007, 02:47 PM

Steve

aaahh now it all becomes clear O0 I know the real reason you dont like this these terms and you have just shown why. O0 It has nothing to do with the underlying science at all, does it?

IAV states clearly that the 'sound' must be inaudible to count as IAV. This still leaves a range of frequencies and amplitudes - but a very restricted one. Using "infrasound" and then claiming err well it can be heard and can be silent and can be this....that...or the other..." is where the real confusion is.

There are many terms you can use - i note you ignored LFN (low-frequenyc noise) and even LFIN (low-frequency inaudible noise) - which is one only coined this year in the field. O0

Just use terms properly in the right context - that is all.

I don't like it because it is non-specific and unhelpful to furthering research into the subject - If we are test ideas then it is essential that we stick to already accepted terms and definitions and we then know exactly what is being discussed.
For example, if Vic had told us if his measurements had been in dB A, dB C or if they were in dB SPL then we would have been able to set the equipment to replicate the level and perhaps better test his hypothesis.

IAV - (which as I said you are championing because you made it up) gives us no information about the source signal making any experiments based upon ideas that use it harder to undertake. I am only fighting for clarity of information. Infrasound as a defintion of sound below c.20Hz is good enough for everyone else to use and we all know what frequency range we are dealing with, all we then need is the SPL to provide the amplitude data. Your term IAV removes information and that's why I don't like it.

Dr B

24th May 2007, 02:53 PM

I'd just like to add my 2 cents to this discussion and hopefully draw it to a close to enable equally constructive argument on other threads.

The argument concerning terms (it appears to be IF vs. IAF) to an outsider viewing the thread for the first time appears to be terms associated with individuals (i.e. IF with Steve & IAF with Jason).

That is not true. The argument is one currently going in in the literature. Steve thinks he can take basic physics definitions (pure physics) and then use that to explain complex biophysical / psychological interactions. There is a difference to be acknowledged between whether the 'sound' is perceived (as all true sound is) or whether it is not (and thus is vibration). Why? Because it is highly likely that the neural landscape will be totally different. I cannot for the life of me see why this is a problem.

Certainly, some of the pointed responses to Steve have implied that he is in error. His PhD, and the experiment, do not exist in a vacuum without supervision, advice, or appropriate literature review. There has also been participation in prior projects (in order to perfect the generating and detection system) that have included leading physicists specialising in acoustics from the National Physical Laboratory, sound recordists and acoustic engineers. In addition, advice and input has come from independent sources, including psychologists who worked with Vic Tandy whilst he conducted his studies. It is as a result of ALL of this advice, input and an extensive literature review that Steve has reached the point he's at now, initially conducting field-based lab work to test a theory and to (in the detection side) disprove or prove the association between IF and haunting experiences.

The problem is whether you are reading the right literature or not. I am aware of many physics references that simply do not work at the perceptual level in a psychological explanation. The field itself acknowledges the confusion - I cant see why you guys cant? :cheesy:

The issue with definition and term as you point out, Dr. B., may be appropriate once a paper reaches publication and you read, in more detail, the whys and wherefores of testing and use of particular terms.

The terms need to make sense and must have clarity.

To start to get personal ("Go back to Psych 101, Steve") is a reflection on the supervision and, therefore, I take it personally.

You are totally worng here, I did make that comment and then went back and removed it - and rephrased it (before reading your comments). Why are you taking anything personally? Psych 101 is undergraduate psych not phD. I believe that if someone is trying to make their case for a position they should understand the basic principles of psychology. Senation and perception being crucial and being totallly ignored. I changed the way I worded that comment - but I stand by the sentiment. Steve appears somewhat unaware of these fundamental and basic principles.

It would be more appropriate to keep your comments to a more academic level. In this instance, though, I get the impression that yourself and Steve will never reach a consensus.

Dr. C.

I have had to respond to many of Steves jibes above and have tried harder than most to keep things on the straight and narrow - but if he is not going to actually think and read about the concepts being discussed then we are at a brick wall.

I think we can continue this discussion if we do not keep going around in circles. Your multiple appeals to authority (cited above) wont really work if those authorities are not relevant to perception. O0

Dr B

24th May 2007, 03:06 PM

I don't like it because it is non-specific and unhelpful to furthering research into the subject

I disagree. It is not perfect - because its a definition not an explanation. But it is far superior to 'infrasound'. Of course other definitions exist - if they are vaild and sound, in the context of the science - use those. But be clear on what you are using and why - that is all.

- If we are test ideas then it is essential that we stick to already accepted terms and definitions and we then know exactly what is being discussed.

Steve - this is logically flawed reasoning (ask your supervisor) - by this account there would be little or no progression in science. We use to think all light was what we saw - guess what - its not!!! This did not just mean inventing terms for the rest of the specturm - but renaming the light we can see as 'visible light' or wavelengths etc. Science evolves - if there is a need to change the terminology then change it - but that need must be justified - otherwise it is counter-productive.

For example, if Vic had told us if his measurements had been in dB A, dB C or if they were in dB SPL then we would have been able to set the equipment to replicate the level and perhaps better test his hypothesis.

I agree - but this supports my arguement more than yours

IAV - (which as I said you are championing because you made it up)

You see steve here is an example of your jibes and failure to understand. IAV works for me (and others) that the type of 'energy' (for want of a better term) must be low-frequency and inaudible. It does no more than that - but it was never meant to. One of the reasons you seem totally confused over this is becasue you are fudging distinctions from physics and trying to make psychological arguments from them. I think it is important to use both - but be clear on the distinction.

...gives us no information about the source signal making any experiments based upon ideas that use it harder to undertake.

Another error steve - its a definition not an explanation. It directs the reader to a band of interest and eliminates even more.

I am only fighting for clarity of information.

wrong - you are propogating muddled thinking.

Infrasound as a defintion of sound below c.20Hz is good enough for everyone else to use and we all know what frequency range we are dealing with, all we then need is the SPL to provide the amplitude data. Your term IAV removes information and that's why I don't like it.

But its not good enough at all as many researchers point to the confusion over it. Three or four researchers have told you this here - and you still ignore them......it is interesting that you seem to have some method for choosing which ones to agree with (which does not appear ot be based on relevant science) O0

The term IAV removes no information at all. Its a definition term, no more no less.

Parascience

24th May 2007, 03:25 PM

You see steve here is an example of your jibes and failure to understand. IAV works for me (and others) that the type of 'energy' (for want of a better term) must be low-frequency and inaudible. It does no more than that - but it was never meant to.

It was not a jibe it was a statement of fact. If I fail to understand then it is because you are trying to use a term that is misleading. How you can say that IAV MUST be low frequency is nonsense. Like I mentioned before if you had used LFIAV I would not be continually taking issue.

One of the reasons you seem totally confused over this is becasue you are fudging distinctions from physics and trying to make psychological arguments from them.

I am not making psychological arguments by fudging distinctions from Physics I am only saying that we must be specific when we are describing Physical factors.

The term IAV removes no information at all. Its a definition term, no more no less.

It removes the frequency information that the term Infrasound provides us with - without that specific information Inaudible Air Vibrations could be at any frequency provided they have an SPL below the range of normal human hearing.

Dr B

24th May 2007, 03:36 PM

It was not a jibe it was a statement of fact. If I fail to understand then it is because you are trying to use a term that is misleading. How you can say that IAV MUST be low frequency is nonsense. Like I mentioned before if you had used LFIAV I would not be continually taking issue.

Now you really are floundering. Read the paper steve at no point are we discussing high-frequency sound. IAV refers to what some have tried to call 'true-infrasound' (I am sure i mentioned this above). 'True-infrasound is infrasound that is not audible. You can use either term - but to call it infrasound (as you have been doing all along) is fundamentlly incorrect and you are adding to the confusion other authors are trying to clear up. I see no problem in using IAV in the present context and people understanding it. You keep selectively picking your context - luckily - I spot this O0

I am not making psychological arguments by fudging distinctions from Physics I am only saying that we must be specific when we are describing Physical factors.

You are fudging. You are not being specific with a generic term that refers to multiple forms of sound (heard / unheard) at the perceptual level.

It removes the frequency information that the term Infrasound provides us with

What frequency information? There is none in the the term 'infrasound' and some go on to claim limits of 20Hz, 18Hz, 16Hz etc - so there is no real agreement there either. You also have consistent ignored amplitude levels - which actually relates to the auditory component. IAV hints to this.

- without that specific information Inaudible Air Vibrations could be at any frequency provided they have an SPL below the range of normal human hearing.

It does pertain to a set of frequencies - yes - but as you have now, at last clearly acknowledged (proving the definition is clear) it is below normal human hearing. Anything that can be heard is just sound.O0

I am glad you now seem to agree. O0

median

24th May 2007, 03:59 PM

Parascience

24th May 2007, 04:08 PM

Now you really are floundering. Read the paper steve at no point are we discussing high-frequency sound. IAV refers to what some have tried to call 'true-infrasound' (I am sure i mentioned this above). 'True-infrasound is infrasound that is not audible. You can use either term - but to call it infrasound (as you have been doing all along) is fundamentlly incorrect and you are adding to the confusion other authors are trying to clear up. I see no problem in using IAV in the present context and people understanding it. You keep selectively picking your context - luckily - I spot this O0

Within this forum it's true most of us know we are talking about low frequencies - although I noted previously that Cuddles was a bit confused and stated that Infrasound could be any sound that was inaudible regardless of frequency which perhaps illustrates why we should have stuck to the work Infrasound which clearly refers to sound energies below 20Hz - although I agree that in some definitions other frequencies (all lower than 20Hz) have been proposed as a cut-off.

What frequency information? There is none in the the term 'infrasound' and some go on to claim limits of 20Hz, 18Hz, 16Hz etc - so there is no real agreement there either. You also have consistent ignored amplitude levels - which actually relates to the auditory component. IAV hints to this.

The term Infrasound is universally accepted to mean sound energy of a low frequency so it provides an important clue about which end of the sound spectrum we are dealing with. IAV does not provide this and could appear to be anywhere within that spectrum.

It does pertain to a set of frequencies - yes

No it doesn't - but Infrasound does!

but as you have now, at last clearly acknowledged (proving the definition is clear) it is below normal human hearing. Anything that can be heard is just sound.O0

I don't ever recall saying anything other than it is below Normal human hearing - but it's the 1st time I can recall you adding that extra and very important word.

I am glad you now seem to agree. O0

And we will agree even more if you either ammend the definition IAV or choose one of the other already accepted definitions so that everyone outside this forum will know precisely what frequency range of sound energy you meanO0

Parascience

24th May 2007, 04:19 PM

Another quick question.

Since the debate has focused on the merits of physical definitions wouldn't it be better to talk in terms of phons?
After all research demonstrates that the threshold of human hearing (amplitude) varies over a wide frequency range.
Although using the term infrasound in reference to a frequency range seems to be a tidy way of describing it (akin to infrared in the EM spectrum; perhaps not the best analogy) it does seem to be meaningless in the context of psychophysical perception.:-\

Phons are a measure of perceived loudness and are a subjective measurement of sound strength not intensity. I'm not arguing any case for perception (Jason could eat me for Breakfast if I tried:smiley:) I am only trying to make a case that we stick to a definition that avoids confusion which IAV does.

Dr B

24th May 2007, 05:26 PM

Within this forum it's true most of us know we are talking about low frequencies - although I noted previously that Cuddles was a bit confused and stated that Infrasound could be any sound that was inaudible regardless of frequency which perhaps illustrates why we should have stuck to the work Infrasound which clearly refers to sound energies below 20Hz - although I agree that in some definitions other frequencies (all lower than 20Hz) have been proposed as a cut-off.

Cuddles etc, is capable of arguing for themselves - I was arguing for my points which were, are you rightly acknowledge, provided in the correct context of low-frequency sound.

The term Infrasound is universally accepted to mean sound energy of a low frequency so it provides an important clue about which end of the sound spectrum we are dealing with.

You are still using the physics view - and as such it still remains irrelevant. Infrasound is a term used for low frequencies (non specific though - which goes against some of your earlier points) but can pertain to audible, inaudible and 'felt' frequencies - it is thus clearly ambiguous when applied to perception.

IAV does not provide this and could appear to be anywhere within that spectrum.

Not true - IAV must be inaudible and so cannot be a frequency that would be audible at natural inensities. Of course it does not give an exact figure - because it would be illogical. People differ and sound perception is not absolute.

In perceptual terms IAV is very helpful because you know that if an experiment claims to investigate IAV then they must provide figures that would suggest the energy is inaudible. It has a perceptual (inaudible) and physical term (air vibration) within the definition. You made a fundamental mistake at the start of this discussion when you recruited all the military stuff as evidence for effects of true-infrasound. This is simply not true - as the intensities are too high (sound was heard). Using IAV as a definition only, would have prevented you and them from making that error. So your earlier errors actually make the case for me. The problem is the type of mistake you made is common to the field and I have heard of many researchers in the field becoming frustrated with this.

Note the Leventhall reference - which is only one of a growing number that are now calling for re-definitions and clarity. My paper was asking for this 2-years ago when I wrote the first draft. Nice to see the field agrees O0 even if you do not.

No it doesn't - but Infrasound does!

No - it does - inaudible ones O0

I don't ever recall saying anything other than it is below Normal human hearing - but it's the 1st time I can recall you adding that extra and very important word.

Nonsense - I have been talking about this all along - please go back and start again if you dont believe me. I have made the distinction clear right from the start - others have picked up on it.

And we will agree even more if you either ammend the definition IAV or choose one of the other already accepted definitions so that everyone outside this forum will know precisely what frequency range of sound energy you meanO0

To ask for a precise frequency range in a definition is ridiculous - we only need a guide that can then be refined. You see steve, I can take a frequency, of a given amplitude, which is inaudible and make it audible without altering frequency or amplitude! The crucial difference is perception!!!! - not any of the variables you seem transfixed upon.

So a precise frequency is not giving you the precision that you think it is!!!! Again - it is guided by perceptual responses and not just physical parameters (though obviously there is a correspondence). A precise frequency gives the illusion of precision. This is the fundamental error in your reasoning. A definition, for our uses here is one which alludes to a perceptual component.

The 'accepted' definitions you talk of are not accepted and are breaking down as we speak - so why go backwards?

Dont get me wrong IAV may not be perfect - but its better than any alternative you have sugegsted and it works well as a definition. The crucial point with this research comes down to whether the sound is audible or not. This is only the first step to much more detailed questions - but it is the crucial one underlying all the publics misunderstanding of infrasound (and your own).

Dr B

24th May 2007, 05:32 PM

Another quick question.

Although using the term infrasound in reference to a frequency range seems to be a tidy way of describing it (akin to infrared in the EM spectrum; perhaps not the best analogy) it does seem to be meaningless in the context of psychophysical perception.:-\

Exactly my point dear sir....8)

Parascience

24th May 2007, 08:24 PM

You are still using the physics view

Glad you spotted that oneO0

and as such it still remains irrelevant.

Not when you're trying to generate it or measure it isn't

Infrasound is a term used for low frequencies (non specific though

Did you just agree with me then???

D'yu know what - let's call this quits till the results are in:-X

Dr B

24th May 2007, 09:41 PM

Glad you spotted that oneO0

But this is your undoing....:-\ and has been all along.

Not when you're trying to generate it or measure it isn't

Steve - dont get me wrong it is important to know the physics when generting and measuring - but your claims that whether or not the sound is audible is irrelevant - has been shown to be woefully inadequate and incorrect. I dont think I am arguing against you in the way you think I am. The terminology is incorrect in this context (human perception and experience) which requires a physical and neuro-cognitive language.

If you want to ignore psychological and biophysical aspects completely - then fine. But IAV is still useful in that context as well (but infrasound still struggles)

Did you just agree with me then???

No - i reiterated my earlier points that you never paid attention to O0

D'yu know what - let's call this quits till the results are in:-X

Sure thing - lets move on from this point. O0

Can you tell us anything about the protocol or would you rather wait? I would totally understand if you don't want to say anything here - but it would be nice to know (i) exposure durations, (ii) exposure conditions (iii) baseline conditions (iv) any screening of participants for sound-thresholds, etc.....(v) Did you expose people to basic singular frequency components or combinations of them? Did you measure the IAV at the device and where people were? Was the 'sound' inaudible - and if so, how did you explicitly test for this?

In the meantime - I wish you well with your work and you must, no matter if you get positive results or null findings, publish your work (once you use an appropriate terminology ;DO0).

Parascience

25th May 2007, 12:41 AM

Can you tell us anything about the protocol or would you rather wait? I would totally understand if you don't want to say anything here - but it would be nice to know (i) exposure durations, (ii) exposure conditions (iii) baseline conditions (iv) any screening of participants for sound-thresholds, etc.....(v) Did you expose people to basic singular frequency components or combinations of them? Did you measure the IAV at the device and where people were? Was the 'sound' inaudible - and if so, how did you explicitly test for this?

In the meantime - I wish you well with your work and you must, no matter if you get positive results or null findings, publish your work (once you use an appropriate terminology ;DO0).

I think for the time being that most of these points might be better addressed within the actual planned publication - as the experiment was a collabarative venture I don't think it would be fair for me to deal with parts of the experiment that others have worked hard on.

Thanks for the good wishes and I am sure that we will return to this interesting topic at that time:scared:

Cuddles

25th May 2007, 10:11 AM

I wholeheartedly agree so let's stick to the accepted definition that Infrasound is all acoustic oscillatory energy below a frequency of 20Hz.

I don't define Infrasound as all sound below 20Hz

Oops.

No, we are attempting to find an effect caused by Infrasound and as we have never stated the Sound Pressure Level that was used in our experiment your assumption that we have included sound that is audible is what makes no sense at all. For the record, our Infrasound generator was producing an SPL of between 60dB SPL and 90dB SPL within the experimental areas - thus in terms of 'normal' human hearing was below the auditory threshold.

for 18.5Hz for example the figure is in excess of 80dB SPL (Watanabe & Muller, 1990).

Oops again.

I'm suprised that as a Physicist you are allowing Dr.B to use such a nonspecific definition as 'IAV' This term does not provide any information about the Frequency or Amplitude of the sound wave being either measured or produced. It is vague and unhelpful to any meaningful research. If he really wanted to find an abbreviation to avoid the use of the definition Infrasound then as a Physicist why didn't you suggest the already commonly used abbreviation 'LFAO' - Low Frequency Acoustic Oscillation as it least we would then know if he was referring to sound that has a Frequency of above or below 20Hz, which I am assuming he means.

I allow him to use it because he has defined what it means. If he just used ot by itself as a vague term then it wouldn't be any better than your use of infrasound. However, he has defined it to mean all air vibrations in the frequency range below about 20Hz with intensity below the normal threshold of human hearing. Which is useful.

So now a Physicist is saying that Infrasound can be re-defined as inaudible sound regardless of frequency:cheesy:

Is this a problem? As I said, in some circumstances this definition could make sense. "Infra" means "below". Below sound - inaudible sound. It's not a common definition, but as long as you make it clear what your definitions are there is no reason this one would not make sense.

The concept of 'audibility' is meaningless in the Infrasound region. Sufficient evidence has accumulated to demonstrate that acoustic stimuli with frequencies as low as 1Hz can not only be heard but can also be described in terms of loudness refelcting differences in human hearing thresholds.

Exactly. Infrasound of sufficient intensity can be heard. Which is what we have been saying all along. If you can hear it it makes no sense to treat it any differently from any other sound.

Furthermore, it has been suggested that a very low frequencies human detection does not occur through hearing in the normal sense. Rather, detection results from non-linearities of conduction in the middle and inner ear which generate harmonic distortions in the higher, more easily audible frequency range. It is also critical to consider to consider waves which are detected through skeletal bones, the ear, harmonics, tactile sensations or resonance within the body organs. Detection raises the possibilty of subjective reactions and may also contribute in complex ways to effects - Physiological and Psychological.

Once again, this is exactly what we are trying to make you understand. If infrasound can be detected by two different mechanisms then you have to seperate them when conducting experiments. If you do not do so then you have no way of telling if people are using a different method of detection or just hearing it normally. Since you make no effort to do so your results will be meaningless.

Determination of any possible effects of Infrasound exposure must consider field data. Real occurences of Infrasound will often include considerable energy above and below 20Hz.

And this is why we have laboratories. In the real world things are often messy and hard to analyse. If we construct simple models to investigate just one aspect of something it can be much easier to understand. By attempting to recreate realistic situations before understanding the basics you will find it impossible to nuderstand anything at all.

I gave up watching Brainiac as it was too difficult for me to understand - so I went and played with my Infrasound generating and Infrasound Measuring Equipment instead which I used my common sense to design and build

Oh dear. Common sense. The very opposite of everything science stands for. Dose human psychology have anything to do with common sense? Does quantum physics have anything to do with common sense? If you try to use common sense to analyse anything you can pretty much guarantee you will get it wrong. What we call common sense often has very little to do with actual reality. I think I may be able to see where your problem is.