title: Factors influencing electrical place pitch perception in bimodal listeners.
abstract: Factors that might affect perceptual pitch match between acoustic and electric stimulation were examined in 25 bimodal listeners using magnitude estimation. Pre-operative acoustic thresholds in both ears, and duration of severe-profound loss, were first examined as correlates with degree of match between the measured pitch and that predicted by the spiral ganglion frequency-position model. The degree of match was examined with respect to (1) the ratio between the measured and predicted pitch percept on the most apical electrode and (2) the ratio between the slope of the measured and predicted pitch function. Second, effect of listening experience was examined to assess whether adaptation occurred over time to match the frequency assignment to electrodes. Pre-experience pitch estimates on the apical electrode were within the predicted range in only 28% of subjects, and the slope of the electrical pitch function was lower than predicted in all except one subject. Subjects with poorer hearing tended to have a lower pitch and a shallower electrical pitch function than predicted by the model. Pre-operative hearing thresholds in the contralateral ear and hearing loss duration were not correlated with the degree of pitch match, and there was no significant group effect of listening experience.
authors.affiliation: The HEARing CRC, Level 1, 174 Victoria Parade, East Melbourne, Victoria 3002, Australia.
authors.forename: Kerrie L
authors.initials: KL
authors.lastname: Plant
authors.affiliation: Bionics Institute, 384-388 Albert Street, East Melbourne, Victoria 3002, Australia.
authors.forename: Hugh J
authors.initials: HJ
authors.lastname: McDermott
authors.affiliation: The HEARing CRC, 550 Swanston Street, Parkville, Victoria 3010, Australia.
authors.forename: Richard J M
authors.initials: RJ
authors.lastname: van Hoesel
authors.affiliation: The HEARing CRC, 550 Swanston Street, Parkville, Victoria 3010, Australia.
authors.forename: Pamela W
authors.initials: PW
authors.lastname: Dawson
authors.affiliation: The HEARing CRC, 550 Swanston Street, Parkville, Victoria 3010, Australia.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Cowan
mesh_terms: D000161:Acoustic Stimulation; D000222:Adaptation, Physiological; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold; D019929:Cochlear Implantation / Q000295:instrumentation*; D003054:Cochlear Implants; D003463:Cues; D004558:Electric Stimulation; D005260:Female; D034381:Hearing Loss / Q000175:diagnosis / Q000503:physiopathology / Q000523:psychology / Q000534:rehabilitation*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D019986:Persons with Hearing Disabilities / Q000523:psychology / Q000534:rehabilitation*; D010898:Pitch Perception; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D013136:Spiral Ganglion / Q000503:physiopathology; D013997:Time Factors