Contribution of auditory cortex to sound localization in the monkey (Macaca mulatta)

Monkeys with lesions of auditory cortex were tested for their ability to localize the source of brief sounds. Although those deprived of primary auditory cortex bilaterally were able to indicate the direction of a sound with near-normal acuity, they were unable to locate its source. This dissociation of abilities suggest that the role of auditory cortex in sound localization is not so much sensory or perceptual as it is auditomotor or associative. Thus, sound localization joins loudness, pitch, and most other traditional attributes of sound as dimensions whose discrimination does not depend on auditory cortex. The question would now seem to turn to whether or not auditory cortex is necessary for any sensory discrimination whatever.