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presented at the 9 th Symposium on Cochlear Implants in Children, Washington, D.C. (April, 2003). Comparing bimodal perception skills in infant hearing-aid and cochlear-implant users. Brittan A. Barker & J. Bruce Tomblin Department of Otolaryngology— Head & Neck Surgery University of Iowa.
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presented at the 9th Symposium on Cochlear Implants in Children, Washington, D.C. (April, 2003) Comparing bimodal perception skills in infant hearing-aid and cochlear-implant users Brittan A. Barker & J. Bruce Tomblin Department of Otolaryngology— Head & Neck Surgery University of Iowa
Acknowledgements Victoria C. Klein Linda J. Spencer Sandie M. Bass-Ringdahl Courtney M. Burke Michelle L. Hughes The University of Iowa’s Cochlear Implant Team The infants and their families who volunteered their time
Research supported in part by… • research grant 2 P50 DC00242 from the National Institutes on Deafness and Other Communication Disorders, National Institutes of Health. • grant RR00059 from the General Clinical Research Centers Program, NCRR, National Institutes of Health. • the Iowa Lions Sight and Hearing Foundation.
Background • The age at which infants undergo surgery for cochlear implants has considerably declined within recent years. • There is a need to systematically collect information regarding hearing-aid and cochlear-implant “benefit” from these infants. • Prior research shows that infants with normal hearing have the capabilities to store information about the acoustic signal and begin to learn from it.
Objectives • …to build on the bimodal perception work of Patterson & Werker (2002, 2003) and determine the feasibility of replicating their findings with infants, who use hearing aids and/or cochlear implants. • …to determine the point in development at which infants, who use hearing aids and/or cochlear implants, are able to successfully match phonetic information from the lips and voice.
Methodology • Design: on-going, longitudinal study that approximates a multiple-baseline design. • Participants: 10 infants’ data (3 females) will be presented; infants were assessed at least once prior to cochlear implantation and previous to cochlear implant stimulation. • Procedure: The Split-Screen Preferential Looking Procedure (SPLP; Hollich, Hirsh-Pasek, & Golinkoff, 2001) was used to assess bimodal perception skills.
Stimuli and apparatus DV camera /a/ versus /i/ video monitor infant caregiver video monitor experimenter images appearing on video monitor for infant’s viewing
Experimental design • The experiment consisted of two phases, a familiarization phase and a test phase. • The familiarization phase was used to introduce the infant to each video in isolation and then in company. No sound was presented. • During the succeeding test phase, the same images were presented simultaneously, side-by-side and sound was introduced.
Coding data • Each infant’s gaze duration, during the test phase, was summed for each display and averaged across stimulus conditions. • This yielded the mean total looking time (in seconds) for each image during the test phase.
Results: individual data, cochlear-implant user CI-02 * p < .05
Results: individual data, cochlear-implant user CI-03 * p < .05
Results: group data * p < .05 n = 10 n = 6 n = 7 n = 3 n = 1
Conclusions • Exploration of bimodal perception skills in infant, cochlear-implant users is feasible. • The cochlear-implant users’ auditory experience via hearing aids was different from the auditory experience via cochlear implants. • Individual differences were noted across the participants’ test sessions.
Future directions • Evaluate and compare the differences in audibility and C-levels across children. • Compare the emergence of bimodal perception and the emergence canonical babbling. • Explore the development of speech perception skills in infants with a variety of hearing levels.
SPLP Example Experiment:bimodal perception of /a/ & /i/ Familiarization: 6 trials (no sound) with 2s ISI of /i/ /a/ /a/ /i/ 9s 9s 9s (2 times) (2 times) Test phase: 4 trials (sound: counterbalance /a/ AND /i/) with 2s ISI of * articulations occur once every 3s, thus 9 artics/trial /a/ /i/ /a/ /i/ * sound presented, left-right positioning, and order of familiarization are counterbalanced—yielding 8 conditions 27s /a/ 27s /i/ (2 times)