Representation of intensity and frequency information in auditory cortex of monkeys performing a simple auditory task

Abstract

Intensity functions were measured for single neurons at the cell's best frequency and at surrounding frequencies within the receptive field. Subjects for these experiments were adult male rhesus monkeys. Single neurons were isolated using a vertical approach to the superior temporal plane. Subsequent electrophysiological and anatomical data indicated that cells were located in cortical areas A1, CM, L, and RL [Merzenich and Brugge Brain Res. 50, 275–296 (1973)]. Data were collected while monkeys were performing a simple auditory reaction‐time task. As shown in this and many previous studies, in the absence of such a uniform behavioral control much variation in responses of auditory cortex neurons is encountered. The reaction time task was also used to provide an ongoing measure of the subject's threshold and suprathreshold hearing during recording of neural responses. Data are reported for encoding of stimulus intensity and frequency and discussed relation to behaviorally measured hearing. [Supported by NIH Grants NS‐08181, PR‐00166, and GM‐00260.]