Assume that a single IPSP has a negative magnitude of -0.5 mV at the axon hillock, and that a single EPSP has a positive magnitude of +0.5 mV. For a neuron with an initial membrane potential of -70 mV, the net effect of the simultaneous arrival of six IPSPs and two EPSPs would be to move the membrane potential to
A) -72 mV.
B) -71 mV.
C) -70 mV.
D) -69 mV.
E) -68 mV.

Question

Quizplus · Accepted Answer

The net effect is calculated by adding the effects of the IPSPs and EPSPs: (6 * -0.5 mV) + (2 * +0.5 mV) = -3 mV + 1 mV = -2 mV. Starting from -70 mV, the membrane potential moves to -72 mV.

Assume That a Single IPSP Has a Negative Magnitude of -0.5