The Mechanism of Discharge Pattern Formation in Crayfish Interneurons

摘要: Excitatory and inhibitory processes which result in the generation of output impulses were analyzed single crayfish interneurons by using intracellular recording membrane polarizing techniques. Individual spikes are initiated orthodromically axon branches summate temporally spatially to generate a main spike; dispersed branch often pace repetitive discharge axon. Hyperpolarizing IPSP's sometimes suppress axonal most these inputs, but other cases may interact selectively with some them. The reverse their polarity at hyperpolarized level potential; they exhibit two discrete time courses indicating different input sources. Outward direct current near causes discharges last, optimal intensities, for 1 15 seconds. relation frequency intensity is linear an early spike interval, above 100 200 impulses/sec. it begins show saturation. In one unit current-frequency curve exhibited portions, suggesting presence spike-generating sites Current threshold measurements, test stimuli durations, showed that both accommodation "early" or "residual" refractoriness contribute determination rate frequencies.