Multidimensional scaling between acoustic and electric stimuli in cochlear implant users with contralateral hearing.
This study investigated the perceptual relationship between acoustic and electric stimuli presented to CI users with functional contralateral hearing. Fourteen subjects with unilateral profound deafness implanted with a MED-EL CI scaled the perceptual differences between pure tones presented to the acoustic hearing ear and electric biphasic pulse trains presented to the implanted ear. The differences were analyzed with a multidimensional scaling (MDS) analysis. Additionally, speech performance in noise was tested using sentence material presented in different spatial configurations while patients listened with both their acoustic hearing and implanted ears. Results of alternating least squares scaling (ALSCAL) analysis consistently demonstrate that a change in place of stimulation is in the same perceptual dimension as a change in acoustic frequency. However, the relative perceptual differences between the acoustic and the electric stimuli varied greatly across subjects. A degree of perceptual separation between acoustic and electric stimulation (quantified by relative dimensional weightings from an INDSCAL analysis) was hypothesized that would indicate a change in perceptual quality, but also be predictive of performance with combined acoustic and electric hearing. Perceptual separation between acoustic and electric stimuli was observed for some subjects. However, no relationship between the degree of perceptual separation and performance was found.
Antwerp University Hospital, Department of Otorhinolaryngology and Head and Neck Surgery, University of Antwerp, Wilrijkstraat 10, 2650 Edegem, Belgium; C. Doppler Laboratory for Active Implantable Systems, Institute of Ion Physics and Applied Physics, University of Innsbruck, Innsbruck, Austria; Thomas More University College, Gezondheid & Welzijn, Logopedie en audiologie, Jozef De Bomstraat 11, 2018 Antwerpen, Belgium. Electronic address: Katrien.vermeire@thomasmore.be.
Katrien
K
Vermeire
David M
DM
Landsberger
Peter
P
Schleich
Paul H
PH
Van de Heyning
D000161:Acoustic Stimulation; D000162:Acoustics; D000328:Adult; D000368:Aged; D001301:Audiometry, Pure-Tone; D001307:Auditory Perception; D003054:Cochlear Implants; D003638:Deafness / Q000503:physiopathology / Q000534:rehabilitation*; D004558:Electric Stimulation; D004566:Electrodes; D006309:Hearing; D006801:Humans; D016018:Least-Squares Analysis; D008875:Middle Aged; D055815:Young Adult