Ghoul Vibrations: press release.

[Dr B]

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......

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]

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]

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

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.

[Dr B]

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.

[Parascience]

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]

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!!! 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]

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]

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!!! 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]

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]

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.

[Dr B]

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

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]

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.

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]

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]

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. Again, it is a case for clarity.

[Parascience]

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

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.