Auditory brainstem responses, electrocochleograms, and cochlear microphonics in the myelin deficient mutant hamster 'bt'

Electrophysiological studies of the auditory pathway were performed on the mutant hamster 'bt' which is known to have myelin deficiencies in the centr al nervous system. Auditory brainstem responses (ABRs), electrocochleograms (EcochGs), and cochlear microphonics (CMs) were recorded. ABRs in 'bt' dem onstrated markedly transformed waveforms with significantly prolonged laten cies. EcochG in 'bt' showed significantly prolonged NI latencies of the com pound action potentials (CAPs) while 'bt' showed normal CMs. The myelin def icient mutant hamster 'bt' may have myelin deficiencies not only in the bra instem auditory pathway but also in the cochlear nerve. (C) 1999 Elsevier S cience B.V. All rights reserved.