Two groups of randomly chosen individuals who lived in two communities
located different distances from the airport were studied. We monitor
ed audiometry and brainstem auditory-evoked potentials to evaluate coc
hlear and retrocochlear functions in the individuals studied. The resu
lts of audiometry measurements indicated that hearing ability was redu
ced significantly in individuals who lived near the airport and who we
re exposed frequently to aircraft noise. Values of pure-tone average,
high pure-tone average, and threshold at 4 kHz were all higher in indi
viduals who lived near the airport, compared with those who lived fart
her away. With respect to brainstem auditory-evoked potentials, latenc
ies between the two groups were not consistently different; however, t
he abnormality rate of such potentials was significantly higher in vol
unteers who lived near the airport, compared with less-exposed counter
parts. In addition, a positive correlation was found between brainstem
auditory-evoked potential latency and behavioral hearing threshold of
high-frequency tone in exposed volunteers. We not only confirmed that
damage to the peripheral cochlear organs occurred in individuals expo
sed frequently to aircraft noise, but we demonstrated involvement of t
he central auditory pathway.