Interaction of sensory feedback: a child-adult comparison of oral sensory and temporal articulatory function.

Recent studies have demonstrated a systematic increase in lingual sensory thresholds and a temporal articulatory reorganization in subjects speaking under exposure to auditory masking. These data suggest that auditory and lingual sensory feedback systems exist in a balanced interaction specific to the oral articulations involved in speech production. The present study attempted to gain additional information on this proposed interaction. Lingual sensory and temporal articulatory measurements were obtained from 10 adults and 10 children under each of four feedback conditions: (1) normal feedback, (2) exposure to binaural auditory masking during speech, (3) topical application of anesthesia to the lingual dorsum prior to speech, and (4) combined masking and anesthesia. Analysis indicated that children had lower lingual sensory thresholds than adults in all conditions and that they were more susceptible to the disruption of auditory feedback. Also, measurements of durations of vowels indicated no age-related differences with durations in both groups increasing when auditory feedback was impaired.