Cortical processing of musical sounds in children with Cochlear Implants

Objective: We studied the neurocognitive mechanisms of musical instrument sound perception in children with Cochlear Implants (CIs) and in children with normal hearing (NH). Methods: ERPs were recorded in a new multi-feature change-detection paradigm. Three magnitudes of change in fundamental frequency, musical instrument, duration, intensity increments and decrements, and presence of a temporal gap were presented amongst repeating 295 Hz piano tones. Independent Component Analysis was utilized to remove artifacts caused by the Cochlear Implants. Results: The ERPs were similar in the two groups across all perceptual dimensions except for intensity increment deviants. CI children had smaller and earlier P1 responses compared to controls, and their MMN responses showed less accurate neural detection of changes of musical instrument, sound duration, and temporal structure. P3a responses suggested that poor neural detection of musical instruments affected their involuntary attention shift. Conclusions: The similarities of neurocognitive processing are surprising in the light of the limited auditory input provided by the CI, suggesting that many types of changes are adequately processed by the CI children. Significance: Our results indicate that CI children's auditory cortical functioning may be enhanced, and difficulties in auditory perception and in attention switching towards sound events alleviated, by multisensory musical activities. (C) 2012 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.