Immature sound localisation and abnormal development.

This investigation tested the hypothesis that high risk infants showing immaturity in localisation of a sound stimulus would be more likely to have appreciable neurodevelopmental dysfunction. The cohort comprised 112 infants, 66 of whom were classified as 'high risk'. Every infant underwent a neurological and developmental assessment, a sound localisation response test, and an audiological examination when necessary. The first examination was performed at age 8-9 months and was repeated between six and eight months later. It was found that if the sound localisation response was mature at the first examination normal development could be anticipated at the second examination. If an immature sound localisation response was shown then considerable dysfunction could be anticipated in about half of the infants. It is suggested that special attention be paid to the maturity of the sound localisation response in infants during auditory screening procedures, and an immature response should alert the examiner to the possibility of appreciable abnormality in development.