NICOTINE patches could someday be used to treat hearing disorders, says a
researcher who has found that the drug seems to make the brain process sounds
more efficiently.
Studies into cigarette smoking and hearing have produced contradictory
results. Some suggest that chronic smoking improves auditory sensitivity, while
several show it impairs sound processing. Others have found no effect at all. So
Ashley Harkrider at the University of Tennessee in Knoxville decided to study
nicotine separately from the thousands of other compounds in cigarette
smoke.
She took 20 non-smoking volunteers and gave them a low dose of nicotine via a
patch. These volunteers had electrodes applied to their scalp near the regions
of the brain that process sounds. Harkrider measured changes in electrical
activity while volunteers listened to different types of noise. Then she
repeated the measurements while they weren鈥檛 wearing the patch.
Advertisement
Nicotine enhances the activity of a neural pathway that helps the brain
鈥渇ilter鈥� out unimportant repetitive sounds, she found. Harkrider plans to test
this finding in behavioural studies that ask participants to pick out certain
sounds from background noise. 鈥淚t may end up that the controlled use of nicotine
will be beneficial in some types of hearing loss or diseases of the auditory
system,鈥� she says.
However, she cautions that the study only applies to nicotine and doesn鈥檛
mean that smoking cigarettes can help people hear over the din of a cocktail
party. Compounds other than nicotine in cigarette smoke may actually harm
hearing, Harkrider says.