Effects of Bilateral Automatic Gain Control Synchronization in Cochlear Implants with and without Head Movements: Sound Source Localization in the Frontal Hemifield

Autor/inn/en	Pastore, M. Torben; Pulling, Kathryn R.; Chen, Chen; Yost, William A.; Dorman, Michael F.
Titel	Effects of Bilateral Automatic Gain Control Synchronization in Cochlear Implants with and without Head Movements: Sound Source Localization in the Frontal Hemifield
Quelle	In: Journal of Speech, Language, and Hearing Research, 64 (2021) 7, S.2811-2824 (14 Seiten) PDF als Volltext Verfügbarkeit
Zusatzinformation	ORCID (Pastore, M. Torben)
Sprache	englisch
Dokumenttyp	gedruckt; online; Zeitschriftenaufsatz
ISSN	1092-4388
Schlagwörter	Assistive Technology; Hearing Impairments; Brain Hemisphere Functions; Human Body; Motion; Auditory Stimuli; Patients; Performance; Listening; Acoustics + Suchen Sie Ihr Suchwort? Hearing impairment; Hörbehinderung; Menschlicher Körper; Bewegungsablauf; Auditive Stimulation; Patient; Achievement; Leistung; Hörvorgang; Zuhören; Akustik
Abstract	Purpose: For bilaterally implanted patients, the automatic gain control (AGC) in both left and right cochlear implant (CI) processors is usually neither linked nor synchronized. At high AGC compression ratios, this lack of coordination between the two processors can distort interaural level differences, the only useful interaural difference cue available to CI patients. This study assessed the improvement, if any, in the utility of interaural level differences for sound source localization in the frontal hemifield when AGCs were synchronized versus independent and when listeners were stationary versus allowed to move their heads. Method: Sound source identification of broadband noise stimuli was tested for seven bilateral CI patients using 13 loudspeakers in the frontal hemifield, under conditions where AGCs were linked and unlinked. For half the conditions, patients remained stationary; in the other half, they were encouraged to rotate or reorient their heads within a range of approximately ± 30° during sound presentation. Results: In general, those listeners who already localized reasonably well with independent AGCs gained the least from AGC synchronization, perhaps because there was less room for improvement. Those listeners who performed worst with independent AGCs gained the most from synchronization. All listeners performed as well or better with synchronization than without; however, intersubject variability was high. Head movements had little impact on the effectiveness of synchronization of AGCs. Conclusion: Synchronization of AGCs offers one promising strategy for improving localization performance in the frontal hemifield for bilaterally implanted CI patients. (As Provided).
Anmerkungen	American Speech-Language-Hearing Association. 2200 Research Blvd #250, Rockville, MD 20850. Tel: 301-296-5700; Fax: 301-296-8580; e-mail: slhr@asha.org; Web site: http://jslhr.pubs.asha.org
Erfasst von	ERIC (Education Resources Information Center), Washington, DC
Update	2024/1/01