Here we are establishing how neurons can "resonate" with inputs coming at particular time intervals. These input impulses must synchronize with the subthreshold oscillations of the target neuron to cause it to fire. In other words, it's not simply the sum of all input impulses and their reaching a threshold that causes firing; they must be timed in a certain way. Otherwise, an input impulse can actually cause inhibition
We can put the networks of such "resonate and fire" neurons together as in this lecture.
Let's remember the big picture. We are looking at
how in individual neurons can plausibly sustain a classical-quantum interface.
En route, we find that - using classical wave interference like this lecture
demonstrates – they can implement important perceptual tasks that
integrate-and-fire has problems implementing. This is our last lecture at this
level; we then move up to groups of neurons before starting next week at the
cognitive level
Please remember the connection with
meditation/consciousness and gamma waves. As lucidly described in Francisco
Varela's conversation with the Dali Lama, what is happening in the brain in
meditation/consciousness is that global gamma waves interact with the
subthreshold oscillations of the neurons. Note that the action potential is of
the order of millivolts, like gamma waves; EEG, a crude measure with electrodes
on the skull, picks up only microvolts. Unlike Varela, we do not believe that
phase synchrony has been established – though it is plausible.
Goleman (2000) “The brain's melody” In Goleman
(ed) Measuring the immeasurable Boulder Co 2000 Pp 201-210
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