Presynaptic activity regulates Na+ channel distribution at the axon initial segment

A nerve cell sends signals to others through action potentials, which begin at the 'initial segment' of the neuron's axon. Here it is shown that the length of this initial segment increases in bird auditory neurons that have been deprived of auditory stimulation. The resulting increase in intrinsic excitability — the tendency to fire action potentials — represents a new form of neuronal plasticity and might contribute to the maintenance of the auditory pathway after hearing loss.