Evaluation of frequency-following potentials in man: masking and clinical studies

The frequency-following potential (FFP) can have applicability in the assessment of hearing-impaired subjects only if it can be shown that its generation is initiated by neurons which have low best frequencies (2.0 kHz or lower). This study presents results from five subjects with high frequency hearing losses and three subjects with normal hearing. Using 500 Hz tone bursts in the presence of continuous noise of various configurations, it has attempted to determine how in normal hearing subjects, the amplitude and latency of the FFP may be affected. Recordings of the FFP in the presence of noise and wave forms from hearing imparied subjects provide evidence that the FFP is initiated in the cochlea largely by neurons whose best frequencies are 2.0 kHz or lower. Hearing impaired subjects may exhibit 'deviant' responses to tone bursts. These FFP responses may be related to peculiarities of the hearing loss and provide, therefore, a potential means for assessing the temporal viability of the low frequency channels of the auditory neuraxis.