Physiological Function and Characteristics
The threshold value controls whether or not the incoming stimuli are important enough to generate an action potential. Normal functioning of the central nervous system entails a summation of synaptic inputs made largely onto a neuron’s dendritic tree. These local graded potentials reach the axon initial segment and build until they manage to reach the threshold value. The larger the stimulus, the greater the depolarization, or attempt to reach threshold. The task of depolarization requires several key steps that rely on anatomical factors of the cell. The ion conductances involved depend on the membrane potential and also the time after the membrane potential changes.
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