Journal article

Effects of chronic cochlear electrical stimulation after an extended period of profound deafness on primary auditory cortex organization in cats

James B Fallon, Robert K Shepherd, Dexter RF Irvine



Extended periods of deafness have profound effects on central auditory system function and organization. Neonatal deafening results in loss of the normal cochleotopic organization of the primary auditory cortex (AI), but environmentally-derived intracochlear electrical stimulation, via a cochlear implant, initiated shortly after deafening, can prevent this loss. We investigated whether such stimulation initiated after an extended period of deafness can restore cochleotopy. In two groups of neonatally-deafened cats, a multi-channel intracochlear electrode array was implanted at 8 weeks of age. One group received only minimal stimulation, associated with brief recordings at 4-6-week intervals,..

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Awarded by NIDCD

Awarded by Grants-in-Aid for Scientific Research

Funding Acknowledgements

This work was funded by the NIDCD (NO1-DC-3-1005 and HHS-N-263-2007-00053-C) and the National Health and Medical Research Council of Australia. The Bionics Institute acknowledges the support that it receives from the Victorian Government through its Operational Infrastructure Support Program. We thank Rodney Millard, Tom Landry, Andrew Wise and Alison Neil for technical assistance, Helen Feng and Jin Xu for electrode manufacture and implantation, Sue Pierce for veterinary advice, Elisa Borg for animal husbandry, and Colette McKay and two anonymous reviewers for comments on an earlier version of the manuscript. None of the authors have any known or potential conflict of interest.