Source: Twitter X

As far as I know, I said that they do pulse (all or nothing) like transistors but that they vary in frequency, which is the substitute for amplitude and change across time.

Depending upon whether you interpret my use of transistors as an analogy (switch) to neurons in their function in the brain or more rigorously as a thing that changes and retains state rather than, as neurons, changes and returns to state – then you might be correct or not. I’m willing to believe you were attempting to add clarity more so than disagree. But your subsequent appeal to the quantum caused me to equate the two claims rendering both false. Instead of the possibility that you were correct regarding the exactness of the similarity between neurons (on-of) vs transistors (on-or-off). Producing this effect requires additional electronic components, usually Flip-Flops or PLC’s.

Neurons communicate primarily through release of action potentials, which are indeed “all-or-nothing” pulses. When a neuron fires an action potential (usually called a spike), it momentarily reverses the electric potential across its cell membrane, which then rapidly returns to its resting state.

This process is similar to an electrical pulse and is indeed all-or-nothing—either the neuron reaches the threshold to trigger an action potential, or it does not.

Next, neurons use what we call “rate coding” where the information is not carried in the amplitude of the action potential (since all action potentials are roughly the same size and shape in a given neuron) but rather in the frequency and timing of these spikes:

… Frequency: A higher rate of firing (more action potentials over a given time period) can indicate stronger intensity or a different type of stimulus. For example, a sensory neuron might fire more rapidly in response to a brighter light or a louder sound.
And;
… Timing: The timing of action potentials can also be crucial, especially in neural circuits where precise timing between the firing of multiple neurons encodes information.

Therefore, my statement that neurons “vary in frequency, which is the substitute for amplitude and change across time” is correct in the context of how information is processed and conveyed by neural action potentials.

Neurons modulate the rate and pattern of these pulses to represent various types of sensory input, motor commands, and other information within the nervous system.

This method of communication differs from how devices like transistors function, as transistors modulate amplitude or turn on/off as switches without an intrinsic “all-or-nothing” pulse similar to action potentials.

Cheers 😉

Reply addressees: @MatthewParrott