🚀 go-pugleaf

"Bob Masta" <NoSpam@daqarta.com> wrote in message 
news:451bc030.1306174@news.sysmatrix.net...
> On Wed, 27 Sep 2006 13:10:28 -0500, "Mike Rieves" <mriev@hotspam.com>
> wrote:
>
> <snip>
>>
>>The Neurophone however, is a totally different animal.
>>I notice that at www.neurophone.com they are talking about ultrasonic
>>transmission, rather than RF transmission, which I think may be plausible,
>>though I'm far from an expert on the subject.
>>
>
> It doesn't matter whether it's ultrasound, RF, microwave, magnetic, or
> electric fields.  The problem is not getting a signal into the head,
> its getting *many* signals into the head in just the right places to
> represent the frequency content of each auditory channel.  Even
> if you drilled a hole and placed an electrode at any site you chose,
> and pumped the audio signal in directly, you would just get a series
> of buzzes in time with the signal peaks.
>
> Once again, the auditory system is not even remotely like radio
> or telephones.  The cochlea breaks down the signal into separate
> frequency components, and each goes to the brain on its own
> nerve.  If you look at the signal on any one of those nerves, it is
> a spike train where the spikes per second is proportional to the
> signal *strength*... not frequency.  The spike rates are in the
> low 100s of spikes per second... definitely not adequate to
> encode anything like audio.  If you stuck your electrode or
> neurophone signal directly into the neuron and applied audio,
> only the peaks that were large enough to exceed the neuron's
> threshold would produce spikes.  After the neuron fires its
> spike, it goes into a "refractory period" where it has to recover
> before it can fire another spike.  So, no possible way to send
> audio over a nerve.  All the nerve carries is information about
> the envelope of its single frequency component, sort of like
> one column of LEDs on one of those home stereo spectrum
> displays, where there are different columns of LEDs for each
> band.  It's the full array of thousands of these that make up
> the experience of hearing.
>
> Now since the Neurophone has no way single out individual
> neurons and send just the right spike rate to each one, the
> best it can do is fire a whole bunch of neurons together.
>
> Think of the task as playing the piano: Normal hearing has
> way more than 88 "keys", but that will do for an example.
> To get a melody, you have to press down different keys
> at different times.  But the Neurophone can only press
> *all* the keys or no keys, it can't single out specific keys
> at specific times.  So lay a board across the piano
> keys and try hitting it in the center with a hammer.
> You can convey *information* this way, but not a melody.
> In the same way, a single-channel stimulation system can
> not convey speech or music to the brain.
>
> Best regards,
>
>

 Have you ever actually experimented with one?