[extropy-chat] "Dead Time" of the Brain

[David Masten]

On Wed, 2006-04-19 at 15:28 -0700, A B wrote:
> But, I assume that the transmission of signals is the major
> constituent of human cognition. That transmission cannot occur without
> the neuron "firing" electrically. During the periods when a neuron is
> not firing (not transmitting signals) I doubt that it contributes to
> cognition any more so than a liver cell (to use John's example) would.
> So the firing rate seems to be the critical and limiting factor.

I'm not a biologist or neuroscientist myself, so that is why I'm wondering.

The analogy that popped into my head was that of a signal pin on a
clocked digital processor. In terms of working with the processor we
only see the signal at our clock rate. So if we have a 1 MHz clock, we
get an 'off' time of (10^-6/10^-43)-1 or (10^38)-1 Planck intervals.

But if we attach an oscilloscope to the pin we see not a bunch of
discrete events but rather a continuous wave. We don't see a series of
discrete events until we get down to a time frame where we see
individual electrons jumping from atom to atom.

Even worse, the brain doesn't have a clock source. So I'm seeing the
signal flow/processing not as discrete events but rather as a continuous
process of nearby neuron fires triggering some biochemical process that
then triggers another neuron and so on.

At any rate, I'm skeptical of calling the brain "dead" between firings.
Just as I remain skeptical that "I" will "wake up" in a new body after
my death. Not that anyone else, even the new "me", will know the
difference! In fact the new "me" will argue it the other way - "I went
into the download, went to sleep, and woke up in this new body. Just as
continuous as going to sleep and waking up. I don't recall dreaming
though. You say the old me died from falling off a rock face?"

Dave