Response of Tactile Receptors to Intermittent Stimulation

Résumé du livre

Observations have been made of the action potentials in single sensory nerve fibres resulting from intermittent stimulation of the receptors in the skin of the frog by means of an interrupted air blast. The following results have been obtained: 1. The receptor produces a single impulse in response to each brief puff of air up to a high frequency of stimulation. 2. The adaptation time to continued intermittent stimulation varies with its character: if the duration of the stimulus (puff of air) is long in relation to the intervening rest periods adaptation occurs within a few seconds or minutes, whereas when the relative durations of these factors are reversed the receptors may continue to follow a high stimulation rate for an hour or more. 3. A continuous air blast applied to the receptors, even when no response is elicited, results in complete adaptation to an immediately following intermittent stimulus, i.e. adaptation may occur as the result of the stimulus without the production of a single impulse. 4. Impulses reaching the end-organ antidromically cause a decrease in its excitability to subsequent stimulation, resembling that occurring when the stimulus is applied directly. 5. The receptors may respond to closely spaced stimuli at a rate bringing successive impulses in the nerve fibre well within the relative refractive period. The action potential of the second impulse recorded from the single nerve fibre is then reduced in magnitude.