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PubMed · 12702879

Environmental noise retards auditory cortical development.

Edward F Chang·Michael M Merzenich
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Abstract

The mammalian auditory cortex normally undergoes rapid and progressive functional maturation. Here we show that rearing infant rat pups in continuous, moderate-level noise delayed the emergence of adultlike topographic representational order and the refinement of response selectivity in the primary auditory cortex (A1) long beyond normal developmental benchmarks. When those noise-reared adult rats were subsequently exposed to a pulsed pure-tone stimulus, A1 rapidly reorganized, demonstrating that exposure-driven plasticity characteristic of the critical period was still ongoing. These results demonstrate that A1 organization is shaped by a young animal's exposure to salient, structured acoustic inputs-and implicate noise as a risk factor for abnormal child development.

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Acoustic StimulationAnimalsAnimals, NewbornAuditory CortexBrain MappingElectrophysiologyFemaleNeuronal PlasticityNeuronsNoiseRatsRats, Sprague-DawleyTime FactorsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Edward F Chang, Michael M Merzenich. 2003-04-18. Environmental noise retards auditory cortical development.. https://doi.org/10.1126/science.1082163

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