Claim your $1M from the Great Randi

[Sheldon]

Perhaps one reason why no formal measurements of these tweaks would show an improvement in noise figures is that they don't actually need to decrease noise to work...

So a certain amount of noise would establish the neurological equivilant of the optimum bias current?

Sheldon

 

[pinkmouse]

It makes a little more sense to me as a mental model if you compare it to HF bias in magnetic tape recording, (but I do know that it is really nothing like that... ).

 

[jan.didden]

[snip]Holy geez, I just checked out Lux in the CIA factbook ..... you guys have an average GDP of $55,000 per capita! You're buying!

We do? We are? Why didn't they tell me??

Jan Didden

 

[jan.didden]

Perhaps one reason why no formal measurements of these tweaks would show an improvement in noise figures is that they don't actually need to decrease noise to work...

Fascinating article!
I can relate to it, I have been reading a collection of articles from IRCAM, the French research institute for music and perception. There were some experiments where a tone was masked and could not be perceived, until some noise was added, and suddenly the previously masked tone stood out like a sore thumb. Fascinating indeed.

Jan Didden

 

[FrankWW]

I googled ' "stochastic resonance" hearing'. Busy field.

Applied Mathematics [>] Information Theory [v]

Stochastic Resonance

A stochastic resonance is a phenomenon in which a nonlinear system is subjected to a periodic modulated signal so weak as to be normally undetectable, but it becomes detectable due to resonance between the weak deterministic signal and stochastic noise. The earliest definition of stochastic resonance was the maximum of the output signal strength as a function of noise (Bulsara and Gammaitoni 1996).

<http://mathworld.wolfram.com/images/entries/see_also.gif> Kramers Rate, Noise

[Links] search

The Stochastic Resonance phenomenon
Since its introduction over ten years ago [see bibliography], stochastic resonance (SR) has become very popular in many fields of natural science as a paradigm which epitomizes noise-controlled onset of order in a complex system.
Although in the recent literature the notion of SR gained broader significance, the archetype of SR models is represented by a simple symmetric bistable process x(t) driven by both an additive random noise, for simplicity, white and gaussian, and an external sinusoidal bias. On keeping the forcing amplitude and frequency fixed, the amplitude of the periodic component of the process, x, grows sharply with the noise intensity until it reaches a maximum and, then, decreases slowly according to a certain power-law.
It was initially suggested that such a behavior results from the attuning of a deterministic with a stochastic time scale, that is, the forcing period To and the switching time T(D) of the un-biased bistable process x(t), respectively.

http://www.umbrars.com/sr/introsr.htm

Mini review article here:
http://eaps4.iap.tuwien.ac.at/~gebeshuber/SR_in_biol_systems_CSF2000.pdf

Jan Didden reported:

There's an interesting test I read in a French book from IRCAM (the perception lab near Paris) with masking, now that you mention it.
I don't recall all the exact details, but it's like this: You generate a tone and an harmonic in a certain ratio. Then you add a third tone, not harmonically related. If the ratio of the third tone is not above a certain level, the listener does not hear it, it is masked by the carrier and the harmonic, he just hears the two harmonics.
Now comes the clincher: You add low level broad band noise, without changing anything else to the set-up, and Bingo! the listener reports hearing THREE tones, the harmonics and the third non-harmonic one.
Can you believe that: you add noise and as a result you hear more separate frequencies. Who said hearing perception was simple and straight-forward?

http://www.diyaudio.com/forums/showthread.php?s=&threadid=38912&perpage=10&highlight=&pagenumber=9
(post #89)

I also added to the google search within results, 'music'.

Found this interesting article

Illusions and ghost resonances: how we could see what isn't there
http://www.apkarianlab.nwu.edu/~dchialvo/upon2002.pdf

Snip:
"Despite important advances, is still not well understood what a sensory neuron encodes. How to be certain that a given spike-train from a sensory neuron is encoding
a particular aspect of the physical world? In this contribution we choose to discuss this aspect by way of an example in which the brain reads something that objectively isn't
there ? The unsolved problem is how the brain extracts the pitch of complex sounds, and the solution proposed is a stochastic nonlinear mechanism which is biologically
plausible. Work in this problem can be traced back to Pythagoras...."

Heavy Duty!:
http://arxiv.org/PS_cache/physics/pdf/9810/9810019.pdf

Sounded to me like dither. So I searched ' "stochastic resonance" dither '. Found some stuff:

This one is interesting:
http://www.eleceng.adelaide.edu.au/personal/mmcdonne/McDonnell_SPIE03.pdf

ABSTRACT
Consider an array of threshold devices, such as neurons or comparators, where each device receives the same input signal, but is subject to independent additive noise. When the output from each device is summed to

give an overall output, the system acts as a noisy Analog to Digital Converter ( ADC) . Recently, such a system was analyzed in terms of information theory, and it was shown that under certain conditions the transmitted
information through the array is maximized for non-zero noise. Such a phenomenon where noise can be of bene t in a nonlinear system is termed Stochastic Resonance ( SR) . The e ect in the array of threshold devices
was termed Suprathreshold Stochastic Resonance ( SSR) to distinguish it from conventional forms of SR, in which usually a signal needs to be subthreshold for the e ect to occur. In this paper we investigate the e ciency of
the analog to digital conversion when the system acts like an array of simple neurons, by analyzing the average distortion incurred and comparing this distortion to that of a conventional ash ADC.

This is the one that makes the psycho/physical connection:
http://www.users.cloud9.net/~cgseife/PRL01186.pdf

It appears we've been in this territory before:
http://www.diyaudio.com/forums/showthread/t-19973.html

Lord! I LOVE the internet!

Jan, I see we crossed paths here

 

[jan.didden]

[snip]Jan, I see we crossed paths here

Indeed. I am very interested in these things. After all, you can get only so much satisfaction out of the umpteenth power amp

What fascinates me even more than how this encoding stuff works is how all the strands are pulled together in the mind. That is literally mind-boggling!
It has been argued that the bandwidth of our sensory input channels amount to about a megabit per second, but that the concious mind can handle only about between 10 to 50 BITS per sec (depending on who you read, but nobody goes over 100).

So there is a lot of what one writer calls EXformation going on: Amalgamating and throwing away of INformation to make the 'picture' digestable to the concious mind.

But your brain is continously processing the information; it is like a continous film strip, with the concious mind like a window sliding over the film focusing its attention on this, then that, part of the picture. No wonder conciousness sometimes misses something significant.

That also means that the brain can (and will) continue to work on a problem you gave it, even when you are concious of something else and 'forgot' that problem. Until all of a sudden you wake up with the solution clearly before you. Aren't humans absolutely wonderfull?

Jan Didden

 

[fdegrove]

Hi,

So there is a lot of what one writer calls EXformation going on: Amalgamating and throwing away of INformation to make the 'picture' digestable to the concious mind.

Fascinating indeed...

This is exactly what I like so much in certain jazz music: it can suggest sooo much to the mind that's never being played, only we imagine it being there.
Next time you listen you would sometimes think you hear other things that aren't there either.

Very powerful stuff...

Until all of a sudden you wake up with the solution clearly before you. Aren't humans absolutely wonderfull?

Absolutely.

Cheers,

 

[Peter Daniel]

Fascinating article!
I can relate to it, I have been reading a collection of articles from IRCAM, the French research institute for music and perception. There were some experiments where a tone was masked and could not be perceived, until some noise was added, and suddenly the previously masked tone stood out like a sore thumb. Fascinating indeed.

Jan Didden

This article comes to mind posted previously in Y B Blue thread:
http://www.diyaudio.com/forums/attachment.php?s=&postid=64650

 

[FrankWW]

speaking of amplifiers....

I'd sure appreciate it if someone who really knows their stuff could comment on this article.

It appears that the note we hear but which is not played has its electronic analogue:

Experimental evidence of "ghost" stochastic
resonance in an electronic circuit

Abstract. We demonstrate experimentally the regime of ghost stochastic resonance
in the response of a Monostable Schmitt-Trigger electronic circuit driven by noise and
signals with N frequencies components: kf0 +?f , (k+ 1) f0 +?f , :::k +nf0 +?f with
k > 1. At the frequency for which the resonance is maximum there is no input energy,
thus this form is called "ghost" stochastic resonance. It is verified that stochastic
resonance occurs at the frequency fr = f0 + ?f k+( N ? 1) =2 , as predicted in the theory.

Note the adobe conversion program does not convert the the math symbols from PDF into HTML properly

http://www.apkarianlab.nwu.edu/~dchialvo/ghostnew.pdf

This is a companion article to the one I referenced in my previous post:

Illusions and ghost resonances: how we could see what isn't there
http://www.apkarianlab.nwu.edu/~dchialvo/upon2002.pdf
A better version of it is this:
"How we hear what isn't there: A neural mechanism for the missing fundamental illusion" Chialvo DR. (Chaos, December 2003)
http://www.imedea.uib.es/~dchialvo/Home/Publications/Papers/03-2003-chialvo.pdf

 

[Prune]

Just a short note concerning the last link: as neuroscience papers go, Chialvo's seems pretty light on experimental evidence (with the exception of Fig.4). I'm not criticising his theory; I'm just saying that in order to show it has any value versus the rest, it needs evidence showing it is a better fit, otherwise it is but speculation. As it stands, I do not think it would have been accepted by a serious neuroscience journal (non-linear science journals like Chaos obviously have different criteria, but do not forget that he's proposing a neurological model here and should be judged from that point of view).

 

[FrankWW]

As it stands, I do not think it would have been accepted by a serious neuroscience journal

Yeah, I wondered about that but it seems a lot of neurological models are being published in things like engineering journals.

The article is slight but then I'm not sure it has to be otherwise. The older experimental data does fit to his theory and I get the feeling, looking at his bibliography, that's all he cares about.

Anyway its just speculation on my part but I have a feeling, not a strong one but it's there, that some of these guys might not want to see him back very soon:

http://www.imedea.uib.es/~dchialvo/Home/Publications/Papers/14-1999-chialvo.pdf

With regard to High Fidelty I'm getting spooked. The only part of the reproduction which should be legitimately non linear is my hearing and it turns out all the other parts, including the room, can be that way.

 

[Prune]

I don't see how the learning mechanism he presents fits within the established model of spike timing dependent plasticity of neurons (STDP is an experimental fact, by the way). Of course, not all neural circuits in the brain use STDP, as tends to be the case with this in most respects, so the proposed mechanism may work in specific neural systems, rather than being the general learning mechanism he seems to imply.

Looks like this guy was at Santa Fe. That's not an institution for exactly mainstream science (and I mean that in a bad way).

 

[geoffkait]

Santa Fe

"Looks like this guy was at Santa Fe. That's not an institution for exactly mainstream science (and I mean that in a bad way)."


On the other hand, Niels Bohr Inst. ain't exactly Podunk U.

Speaking of neural theories and such, a bit surprised noone has mentioned Sheldrake's The Presence of the Past.

 

[geoffkait]

Sheldrake and the extended mind

Speak of the devil, I just noticed the following event taking place 12 Oct:

2nd October 2004
Rupert Sheldrake Online
<a href="http://www.sheldrake.org"> http://www.sheldrake.org </a>
L10
RESEARCH SEMINAR WITH RUPERT SHELDRAKE
Tuesday Oct 12, in London.

Rupert writes:
I will be holding a workshop on Tuesday Oct 12 at my home in Hampstead
on research on the Extended Mind. I will discuss recent developments
and plan to try out a series of new experiments on the sense of being
stared at, and also on telepathy. Some of these tests have never been
tried out in a group setting before. They are simple, fun to do and may
also help you to develop your psychic sensitivity. No previous
experience is required.

So please come and take part if you can, and spend a day helping to
pioneer the frontiers of research.

The workshop will be from 10 am to 5 pm at 20 Willow Road, London NW3,
right next to Hampstead Heath, and 6 minutes walk from Hampstead
Underground Station.

The cost is £30, payable on the day, and includes a vegetarian lunch.
Numbers are limited, so places will be allocated on a first come first
served basis. To book, please email my assistant Pam Smart at
pam@telepet.demon.co.uk, or ring her at 01706 82 5278

If you have any comments or suggestions on this Mailing List, please email us on info@sheldrake.org
Best wishes,
Editor

 

[Prune]

I would like to add to the discussion previously in this thread regarding the relationship or lack thereof between mind and quantum theory.

The following online articles support my viewpoint from two different perspectives. This one from a physics point of view, and this one from a philosophy point of view. The latter is a response to the proposals of Stapp, which have numerous objections from other authors, for example Mohrhoff (search the LANL preprint archive at xxx.lanl.gov).

Additionally, I would like any comments from those of you familiar with the second-order representation theory of consciousness that Damasio describes in his 1999 book The Feeling of What Happens. I have failed to find any major criticisms from a neurology/psychology point of view (as opposed to problems with details). I'm not really interested in philosophical objections, as I find that philosophers not grounded in science can argue any point of view regardless of how ludicrous.

 

[Prune]

No comments?

 

[jan.didden]

I ordered the Damasio book. Gimme a break !

Jan Didden

 

[geoffkait]

On the subject,

Intro to ideas of David Bohm at:

http://www.theosophy-nw.org/theosnw/science/prat-boh.htm

 

[Prune]

Bohm's causal interpretation is a type of hidden variables interpretation originally developed by de Broglie. This class of interpretations is just about the least popular one.

 

[geoffkait]

I always seem to climb aboard the least popular interpretations, like Sheldrake and Bohm. At least Einstein thought Bohm might be onto something (of course, that could be interpreted a couple ways).