The Integrative Action of the Nervous System #219975

Introductory — CO — ordination IN the simple reflex Argument: The nervous system and the integration of bodily reactions. Characteristics of integration by nervous agency. The unit mechanism in integration by the nervous system is the reflex. Coordination of reflexes one with another. CO ordination in the simple reflex. Conduction in the reflex-arc. Function Of the receptor to lower for its reflex-arc the threshold value Of one kind Of stimulus and to heighten the threshold value of all other kinds of stimuli for that arc: it thus confers selective excitability on the arc. Differences between con duction in nerve-trunks and in reflex-arcs respectively. These probably largely referable to the intercalation of synaptic mem branes in the conductive mechanism Of the arc. Latent time of reflexes. Reflex latency inversely proportional to intensity of stimulation. Latency Of initial and incremental reflexes. None of the latent interval consumed in establishing connec tion between the elements Of a resting arc. After-discharge a characteristic Of reflex reactions. Increase of after-discharge by intensification of the stimulus, or by prolongation Of short stimuli. Inertia and momentum of reflex-arc reactions.