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G6Tanuki · 15th Sep 2018, 2:23 pm

Human perception depends on neurons to transmit the signals from the 'sensors' to the brain for analysis.

Neurons are a bit like thyratrons: they have a 'trigger' potential which needs to be reached before the neuron fires and 'saturated' (so transmitting the impulse down the chain to the next neuron) followed by a 'recovery' period during which the various neurotransmitter chemicals in the synapse are regenerated.

A neuron cannot reliably be 'partially' fired - once activated it 'goes all the way', just like a thyratron.

So essentially they're a bit like a Schmitt-Trigger-monostable! And Digital!

This is important - the need to reach the 'trigger' potential before firing provides a kind of protection against low-level crosstalk between the bundles of adjacent neurons that make up a nerve (think of it like a 'squelch' control) while the need for the recovery-period before a neuron can activate again provides a finite limit to the number of impulses in any unit of time that the brain receives, preventing it from having a 'buffer overrun'.

15th Sep 2018, 2:23 pm	#58
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 14,007	Re: The Persistence of Analogue Human perception depends on neurons to transmit the signals from the 'sensors' to the brain for analysis. Neurons are a bit like thyratrons: they have a 'trigger' potential which needs to be reached before the neuron fires and 'saturated' (so transmitting the impulse down the chain to the next neuron) followed by a 'recovery' period during which the various neurotransmitter chemicals in the synapse are regenerated. A neuron cannot reliably be 'partially' fired - once activated it 'goes all the way', just like a thyratron. So essentially they're a bit like a Schmitt-Trigger-monostable! And Digital! This is important - the need to reach the 'trigger' potential before firing provides a kind of protection against low-level crosstalk between the bundles of adjacent neurons that make up a nerve (think of it like a 'squelch' control) while the need for the recovery-period before a neuron can activate again provides a finite limit to the number of impulses in any unit of time that the brain receives, preventing it from having a 'buffer overrun'.