Slow current changes underlying square shaped potential waves in warmed Aplysia neurones.

On warming, the regularly firing L11 neurone of Aplysia turns into a bursting-type neurone. The bursts of spikes are produced by slow square waves which can also be obtained at room temperature by adding TTX or Co++. Experiments with slow ramp voltage clamp show that warming induces a negative slope (or negative resistance) on the current-voltage characteristic and very slow current variations (r = 10 to 50 sec) in response to potential changes. The square waves are explained by these two phenomena.