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L D HARMON

Publications and source records attributed to L D HARMON.

5 recordsLinked to original sources

AUDITORY NERVE: ELECTRICAL STIMULATION IN MAN.

Auditory perceptions produced in a person deaf to acoustic stimulation were studied by electrically exciting the auditory nerve through permanently implanted electrodes. Pulsed current as small as 1 microampere peak-to-peak could be perceived. Pitch, as reported by the subject, varied with electrode selection, current amplitude, and pulse repetition rate from about 70 to at least 300 pulses per second. Loudness increased with amplitude and duration of pulse stimuli, and to a lesser extent with repetition rate. The total range in amplitude of the stimulus, from threshold to an uncomfortable loudness, was 15 to 20 decibels. Simultaneous stimulation in separate electrodes produced a number of complex effects.

Acoustic Stimulation↗

NEUROMIMES: ACTION OF A RECIPROCALLY INHIBITORY PAIR.

Two electronic neuron models (neuromimes) connected to a common excitatory input and having both self- and mutual-inhibition were used to simulate the pulse patterns which control wing musculature in certain insects. With variation of stimulus frequency, firing patterns changed in discrete steps. Pattern change was found to be hysteretic: the pattern elicited by a given stimulus frequency depended on whether that frequency was approached from above or below. Pattern selection could be controlled by the injection or deletion of a single pulse in the stimulus pulse-train as well as by smooth frequency change.

Animals↗