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peter-u-diehl / stdp-mnist

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How to understand v_thresh_e #6

Open zuotengxu opened 5 years ago

zuotengxu commented 5 years ago

Hi! Thanks for the contribution of your code "stdp-mnist". I have a question about the equation of “v_thresh_e = '(v>(theta - offset + ' + str(v_thresh_e) + ')) * (timer>refrac_e)“ （1） AND “ neuron_eqs_e += '\n dtimer/dt = 100.0 : ms' ” （2）

I don't understand what the meaning of ”timer” is increased by 100ms each period,
AND ”timer>refrac_e“， can you explain that？ thank you！

CloudyDory commented 5 months ago

I have similar question. I guess timer is a temporary variable counting the time after the last spike, and timer > refrac_e checkes whether the refractory period has passed. But I don't understand why timer is increased by 100ms each period too.

I also don't understand the meaning of variable offset. It is set to 20 mV, so wouldn't theta - offset + v_thresh_e make the firing threshold even lower?