Electrically evoked potentials in cochlear implant subjects

Abstract

A series of experiments was performed to study electrically evoked potentials as indicators of subject response to cochlear implantation. 1. Brain stem evoked responses to electrical stimulation were compared to those obtained by acoustic stimulation in guinen pigs. Tlie response pattern was similar and was independent of the site of placement of the stimulus electrode (cochlear base or apex) or of the extracochlcnr ground electrode (eustachian tube or temporalis muscle) when evoked electrically. 2. Electrically evoked middle latency responses were recorded and compared to subjective behavioral thresholds in patients who had received a single channel cochlear implant (House-Urban). The behavioral responses to the same stimuli were similar. 3. Electrically evoked auditory brain stem responses were studied in single channel cochlear implant subjects (3M/House). When evoked electrically, potential latencies were shorter and in- Lerpcak intervals narrower than acoustically evoked potentials. © The American Laryngological, Rhinological & Otological Society, Inc.