Developmental Changes in Nonhuman Primate Patterns of Brain Lateralization for the Perception of Speech Cues: Neuroelectrical Correlates
This chapter provides a review of recent evoked potential investigations that have focused on comparisons between human and nonhuman primates. Both the published literature reviewed here and the new research data from rhesus monkeys concern one aspect of auditory perception for speech and related nonspeech cues-voice onset time (VOT). This cue has long been recognized as important for the perception of human speech information (Liberman, Cooper, Shankweiler, & Studdert-Kennedy, 1967). More recently, work has emerged that ties the perception of such information to brain response patterns in humans from infancy into adulthood (Molfese & Betz, 1988). However, little information is available concerning the perception of this information by nonhuman primates. The purpose in reviewing both the human and nonhuman reports in the present article is to address the origins of human speech discrimination abilities and the cross-species similarities in brain responsiveness in this process.