PMID: 9442843Jan 1, 1997Paper

Injury-induced reorganization of frequency maps in adult auditory cortex: the role of unmasking of normally-inhibited inputs

Acta Oto-laryngologica. Supplementum
Dexter R F Irvine, Ramesh Rajan

Abstract

Restricted cochlear lesions in adult animals, causing partial deafness, result in a reorganization of primary auditory cortex (AI) such that the region deprived of its normal input by the lesion is occupied by an expanded representation of peri-lesion cochlear regions, and hence of peri-lesion frequencies. One possible mechanism underlying the change in frequency responsiveness involved in such reorganization is that inputs to the cortical neurons at frequencies at and near their "new" post-lesion characteristic frequencies (CFs) are normally present but suppressed by inhibition, and are "unmasked" by the effects of the lesion. Evidence in support of this explanation is provided by two-tone forward-masking experiments which reveal that many AI neurons receive surround inhibitory input. When input to such neurons at their CF is reduced by an intense temporary-threshold-shift (TTS)-inducing stimulus, the response areas of some neurons expand into the region of their inhibitory surrounds, the effect that would be expected if unmasking were involved in cortical reorganization. In other neurons, however, response areas contracted after the TTS-inducing stimulation. Although unmasking of normally-inhibited inputs is likely to contrib...Continue Reading

References

Mar 12, 1992·Nature·C D Gilbert, T N Wiesel
Jan 1, 1991·Annual Review of Neuroscience·J H Kaas
Apr 15, 1989·The Journal of Comparative Neurology·D Robertson, D R Irvine
Apr 20, 1984·The Journal of Comparative Neurology·M M MerzenichJ M Zook
Jan 1, 1995·Annual Review of Neuroscience·N M Weinberger
May 1, 1995·Journal of Neurophysiology·M B Calford, M N Semple
Mar 15, 1993·The Journal of Comparative Neurology·J F WillottS L McFadden
Feb 1, 1993·Journal of Neurophysiology·S A ShammaH Versnel
Oct 1, 1996·Clinical and Experimental Pharmacology & Physiology·D R Irvine, R Rajan
Nov 1, 1958·Journal of Neurophysiology·Y KATSUKIT WATANABE

❮ Previous
Next ❯

Citations

Nov 4, 2011·Neuropsychopharmacology : Official Publication of the American College of Neuropsychopharmacology·Sophia VinogradovEtienne de Villers-Sidani
Jan 29, 2008·Cerebral Cortex·Vibhakar C KotakDan H Sanes
Jan 21, 2000·The Journal of the Acoustical Society of America·P A Busby, G M Clark
Jan 27, 2007·Otology & Neurotology : Official Publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology·Hilke BartelsFrans W J Albers

❮ Previous
Next ❯

Related Concepts

Related Feeds

Auditory Perception

Auditory perception is the ability to receive and interpret information attained by the ears. Here is the latest research on factors and underlying mechanisms that influence auditory perception.