@article {Moore8704, author = {David R. Moore and Jemma E. Hine and Ze Dong Jiang and Hiroaki Matsuda and Carl H. Parsons and Andrew J. King}, title = {Conductive Hearing Loss Produces a Reversible Binaural Hearing Impairment}, volume = {19}, number = {19}, pages = {8704--8711}, year = {1999}, doi = {10.1523/JNEUROSCI.19-19-08704.1999}, publisher = {Society for Neuroscience}, abstract = {Conductive hearing loss, produced by otitis media with effusion, is widespread in young children. However, little is known about its short- or long-term effects on hearing or the brain. To study the consequences of a conductive loss for the perception and processing of sounds, we plugged the left ear canal of ferrets for 7{\textendash}15 months during either infancy or adulthood. Before or during plugging, the ferrets were trained to perform a binaural task requiring the detection of a 500 Hz tone, positioned 90{\textdegree} to the right, that was masked by two sources of broad-band noise. In one condition ({\textquotedblleft}control{\textquotedblright}), both noise sources were 90{\textdegree} right and, in the second condition ({\textquotedblleft}bilateral{\textquotedblright}), one noise source was moved to 90{\textdegree} left. Normal ferrets showed binaural unmasking: tone detection thresholds were lower (mean 10.1 dB) for the bilateral condition than for the control condition. Both groups of ear-plugged ferrets had reduced unmasking; the mean residual unmasking was 2.3 dB for the infant and 0.7 dB for the adult ear-plugged animals. After unplugging, unmasking increased in both groups (infant, 7.1 dB; adult, 6.9 dB) but not to normal levels. Repeated testing during the 22 months after unplugging revealed a gradual return to normal levels of unmasking. These results show that a unilateral conductive hearing loss, in either infancy or adulthood, impairs binaural hearing both during and after the hearing loss. They show scant evidence for adaptation to the plug and demonstrate a recovery from the impairment that occurs over a period of several months after restoration of normal peripheral function.}, issn = {0270-6474}, URL = {https://www.jneurosci.org/content/19/19/8704}, eprint = {https://www.jneurosci.org/content/19/19/8704.full.pdf}, journal = {Journal of Neuroscience} }