Trials with the auditory response cradle. 1--Neonatal responses to auditory stimuli

The Auditory Response Cradle enables physiological response measures to be recorded from the neonate. Auditory responses are detected in the form of head rotation, startle, body activity and respiration changes. This paper reports the results of trials with 203 neonates using 250 and 1000 Hz pure tone and broad band noise stimuli. Response criteria are determined and spontaneous control 'responses' compared with those resulting from stimulus presentation. The response rate is correlated with the measured intra-meatal sound pressure level. Clear response thresholds are determined for all three stimuli. The sharpness of these motor thresholds is discussed and found to have significant implications for cost-effective neonatal auditory screening.