Auditory Steady-State Responses and Speech Feature Discrimination in Infants

Purpose: The aim of this study was to determine whether there was a correlation between auditory steady-state responses (ASSRs) for complex toneburst stimuli and speech feature discrimination (SFD) abilities in young infants.

Study Sample: Seventeen infants (mean age = 9.4 months) and 21 adults (mean age = 27 years) with normal hearing had ASSR and SFD tests.

Data Collection: The ASSR test employed an eight-component complex toneburst stimulus; threshold and input–output functions were determined as level was systematically varied. The SFD test utilized an observer-based, visual-reinforcement test procedure to determine the infant's ability to detect the speech feature change from /ba/ to /da/.

Results: The correlation of the group mean /ba/–/da/ discrimination performance (percent correct) with the group mean ASSR score (percent responses present) ranged from r = 0.64 for the 1500 Hz amplitude-modulated and frequency-modulated tone burst to 0.99 for ASSRs for all stimulus components; however, correlations between ASSRs and SFD scores for individual subjects were modest.

Conclusion: The ASSR and SFD results appear to reflect the audibility of the stimuli.

Key Words

Auditory evoked potentials - infants - speech audiometry