Reduced acoustic and electric integration in concurrent-vowel recognition

• Published in: Scientific reports Vol. 3; no. 1; p. 1419
• Main Authors: Yang, Hsin-I, Zeng, Fan-Gang
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 11.03.2013; Nature Publishing Group
• Subjects: 631/378/2619/1387; 631/378/2619/1592; 639/166/985; 692/308/409; Acoustics; Cochlea; Deafness; Ear; Efficiency; Hearing loss; Humanities and Social Sciences; Integration; multidisciplinary; Prosthetics; Science; Speech
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep01419

The present study used concurrent-vowel recognition to measure integration efficiency of combined acoustic and electric stimulation in eight actual cochlear-implant subjects who had normal or residual low-frequency acoustic hearing contralaterally. Although these subjects could recognize single vowels (>90% correct) with either electric or combined stimulation, their performance degraded significantly in concurrent-vowel recognition. Compared with previous simulation results using normal-hearing subjects, the present subjects produced similar performance with acoustic or electric stimulation alone, but significantly lower performance with combined stimulation. A probabilistic model found reduced integration efficiency between acoustic and electric stimulation in the present subjects. The integration efficiency was negatively correlated with residual acoustic hearing in the non-implanted ear and duration of deafness in the implanted ear. The present result suggests a central origin of the integration deficit and that this integration be evaluated and considered in future management of hearing impairment and design of auditory prostheses.