Stronger bilateral efferent influences on cochlear biomechanical activity in musicians than in non-musicians

The auditory sensory end organ is under the control of the central nervous system via efferent projections. Contralateral suppression of otoacoustic e missions (acoustic signatures of the cochlear biomechanical activity) provi des a non-invasive approach to assess olivocochlear efferent activity in hu mans. Using this approach, the present study compared professional musician s with musically-inexperienced subjects. The results revealed stronger bila teral cochlear suppression, suggesting larger efferent influences in both e ars, in musicians. Furthermore, in indicating no difference in left/right a symmetry of efferent-mediated suppression between the two groups, the prese nt findings suggest that the observed differences in olivocochlear activity reflect bilaterally-enhanced activity of the cortical auditory structures in musicians rather than differences in cerebral hemispheric asymmetry betw een the two groups. (C) 1999 Elsevier Science Ireland Ltd. All rights reser ved.