Bilateral electrical stimulation of a congenitally-deaf ear and of an acquired-deaf ear

• Published in: Acta oto-laryngologica Vol. 111; no. 2; p. 263
• Main Authors: Pelizzone, M, Kasper, A, Hari, R, Karhu, J, Montandon, P
• Format: Journal Article
• Language: English
• Published: England 1991
• Subjects: Cochlear Implants; Deafness - congenital; Deafness - physiopathology; Electric Stimulation - methods; Evoked Potentials, Auditory - physiology; Evoked Potentials, Auditory, Brain Stem - physiology; Female; Humans; Magnetoencephalography; Middle Aged; Speech Perception - physiology
• ISSN: 0001-6489
• DOI: 10.3109/00016489109137385

Two identical multichannel intracochlear prostheses were implanted in the same patient. The first prosthesis, implanted in the congenitally-deaf right ear, elicited clear sound perception but no speech recognition. After 2 years, a second prosthesis, implanted in the acquired-deaf left ear, enabled the patient to understand speech without lip-reading. Brainstem and middle-latency evoked potentials were similar with electrical stimulation of both ears and resembled those evoked by acoustic stimuli in subjects with normal hearing. Cortical electric and magnetic responses differed for right- and left-sided electrical stimulation suggesting that stimulation of the congenitally-deaf ear elicited an abnormal activation of the auditory cortex. These results suggest that only cortical responses were affected by the different histories of deafness of the ears.