CONTROL OF AUDITORY CORTEX TO THE CELL ACTIVITIES IN CONTRALATERAL CORTEX

Abstract

This paper deals with the effects of cortical stimulation(ipsilateral to sound given ear) by the electrical pulses on the tonal responses induced from contralateral auditory cortex, to clarify the neurological mechanism of delicate sound perception in the cortex.
As the response to sound, the impulse of a single unit was recorded by a microelectrode at the first and second auditory response field.The electrical stimuli were applied at the place anato- mically symmetrical to the recording point.
Total of 65 unitary responses was obtained. Fifty responses of them were suppressed, 8 aug- mentated by the electrical stimuli and 7 remained unchanged.The augmentative effects were not so constant as the suppressing one.Dual effects, suppression and augmentation to the same unit, were shown in some cases.
The effects of the conditioning stimuli were varied according to the change of frequencies of test tone stimuli e.g.augmentation in 2000 cps and suppression in 1500 cps.
The discussion was done on the reactivity change of the cell by the electrical pulses applied at contralateral cortex, on the connective route bet- ween the auditory cortices of both sides, and on the significance of the interaction by this functio- nal connection between both auditory cortices in sound perception of the cortex.