Auditory evoked responses to names for different objects: Cross-modal processing as a basis for infant language acquisition.

Abstract

Evoked potential techniques were used to study the acquisition of names for different objects in 14-month-old infants. Auditory evoked responses (AERs) were recorded from each infant by scalp electrodes positioned over frontal, temporal, and parietal regions of each hemisphere before and after several days of training in which nonsense consonant-vowel-consonant-vowel bisyllables were used by parents to consistently name novel objects. Analyses of the AERs collected during the posttraining session indicated that two portions of the brain response discriminated a versus a occurring between the auditorily presented names and the objects held by the infants. Specifically, an early occurring portion of the AER recorded from bilaterally placed frontal electrodes and a late occurring response detected at only the left hemisphere electrode sites discriminated between situations when a match occurred between the object and its name versus those in which there was a mismatch between the name and object. No such differences were found in the pretraining AER data. Results are viewed as a preliminary step in the neuropsychological study of word concept development using electrophysiological measures.