The Developmental Trajectory of Spatial Listening Skills in Normal-Hearing Children

Purpose: To establish the age at which children can complete tests of spatial listening and to measure the normative relationship between age and performance. Method: Fifty-six normal-hearing children, ages 1.5-7.9 years, attempted tests of the ability to discriminate a sound source on the left from one on the right, to localize a source, to track moving sources, and to perceive speech in noise. Results: Tests of left-right discrimination, movement tracking, and speech perception were completed by 75% of children older than 3 years. Children showed adult levels of performance from age 1.5 years (movement tracking), 3 years (left-right discrimination), and 6 years (localization and speech in noise). Spatial release from masking--calculated as the difference in speech reception thresholds between conditions with spatially coincident and spatially separate speech and noise--remained constant at 5 dB from age 3 years. Data from a separate study demonstrate the age at which children with cochlear implants can complete the same tests. Assessments of left-right discrimination, movement tracking, and speech perception were completed by 75% of children who are older than 5 years and who wear cochlear implants. Conclusion: These data can guide the selection of tests for future studies and inform the interpretation of results from clinical populations.