Spiking Neuron

634

10:47:30

Simple circuit for artificial spiking neuron (brain cell), loosely based on Hodgkin-Huxley model.
Circuit implements leaking integrate-and-fire mechanism.

Push button on the left side of the circuit represents input - SYNAPSE. Input current is integrated until threshold (600mV in artificial neuron, -60mV in real neuron) is reached, then neuron fires producing ACTION POTENTIAL (2V in artificial neuron, 100mV in real neuron). Next, neuron is temporarily deactivated and does not react to input - REFRACTORY PERIOD. Input current constantly leaks from the cell membrane driving cell towards RESTING potential (0V in artificial neuron, -75mV in real neuron).
Load resistor and voltmeter on the right side represent output - AXON.

Demonstration:
HOLD push button to inject input current. Observe resulting voltage spikes (green line) on the load resistor. Continuos injection of the current will result in oscillation - so called SPIKE TRAIN.

Next:
SEARCH for "Tiny Neural Network" circuit with 3 of these neurons interconnected.

published 9 years ago

hurz

9 years ago

You think we are just a modular collection of billions of RC Oscillators. For me it looks like an epileptic attack!

rej

9 years ago

@hurz: well, at least Hodgkin and Huxley thought so after inspecting squid neurons in 60s. That said, 60s were the crazy years ;)

hurz

9 years ago

Right

simonlovescats

2 years ago

I see ————————————————————————————————————————————— this

simonlovescats

2 years ago

I didn’t see the push button no

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