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Answer to question in part (b):

Discuss how the rolloff in peak depolarization with increasing stimulus frequency is related to the rolloff in total spike count observed in the previous problem.

The reason that the total spike count decreases with increasing frequency is related to the lowpass filtering property of the RC membrane. For the same stimulus amplitude, a higher frequency stimulus results in a smaller membrane voltage swing...this is most pronounced for stimulus frequencies above the "knee" of the gain curve which occurs at a frequency f = 1/(2*pi*Tau_m). In this case Tau_m is 10 msec and the "knee" occurs near f = 16 Hz.