Sympathectomy improves the ear's resistance to acoustic trauma – could stress render the ear more sensitive?
Version of Record online: 18 JUL 2008
European Journal of Neuroscience
Volume 13, Issue 2, pages 405–408, January 2001
How to Cite
Horner, K. C., Giraudet, F., Lucciano, M. and Cazals, Y. (2001), Sympathectomy improves the ear's resistance to acoustic trauma – could stress render the ear more sensitive?. European Journal of Neuroscience, 13: 405–408. doi: 10.1046/j.0953-816X.2000.01386.x
- Issue online: 18 JUL 2008
- Version of Record online: 18 JUL 2008
- Received 17 August 2000, revised 27 October 2000, accepted 2 November 2000
- guinea pig;
Emotional stress is a phenomenon experienced by many people at some time in their lives. Some of its early manifestations, such as unbearable loudness of ambient sounds and sensations of dizziness, might be linked to inner ear dysfunction. Although the inner ear is supplied with a substantial sympathetic innervation, previous studies have failed to demonstrate any significant functional impact. We show here that in the awake guinea pig and following unilateral ablation of the superior cervical ganglion, the temporary threshold shift induced by a 1-min exposure to 8 kHz pure tone at 96 dB sound pressure level was reduced by as much as 40 dB. Of interest, the protective effect was bilateral suggesting an intimate relationship between the sympathetic and the olivocochlear efferent systems. The data presented here provide new evidence for a key role for the sympathetic system in modulating temporary threshold shifts following exposure to moderate sound stimulation. This opens new perspectives for investigation of sympathetic control in noise-induced permanent hearing losses.