Functional changes in central auditory pathways resulting from cochlear diseases.
Salvi-RJ; Henderson-D; Boettcher-FA; Powers-NL
Central auditory processing: a transdisciplinary view. Katz J, Stecker NA, Henderson D, eds. St. Louis, MO: Mosby Year Book, 1992 Sep; :47-60
This report reviewed some of the functional changes occurring in the central auditory system of individuals who suffer from sensorineural hearing loss. The authors reviewed the enhancement of evoked potential amplitude with peripheral loss, the altering of the normal balance between the excitatory and inhibitory inputs that impinge on individual neurons in the central auditory pathway, and tonotopic reorganization in the auditory cortex. Current knowledge has forced a change from the traditional view of the central auditory system to one which allows that functional changes may occur in the central auditory system as a result of cochlear damage. Such damage causes the tonotopic organization of the auditory cortex to undergo significant rearrangement in adult animals. The over representation of neurons in the inferior colliculus with characteristic frequencies bordering the hearing loss may possibly promote the abnormally large amplitude evoked responses observed in many studies. If the evoked response amplitude enhancement results from tonotopic reorganization, it would suggest that the tonotopic reorganization occurs as far peripherally as the cochlear nucleus. Clinical and practical significance which may be ascribed to tonotopic reorganization and evoked response amplitude enhancement may include loudness recruitment and loudness intolerance, and possibly tinnitus.
NIOSH-Grant; Noise-induced-hearing-loss; Industrial-noise; Laboratory-animals; Sensory-thresholds
Katz-J; Stecker-NA; Henderson-D
Central auditory processing: a transdisciplinary view
State University of New York, Buffalo, New York