Medicine and Health Sciences Commons^™

Spontaneous Vocal Matching In Mothers And Their Hearing Impaired Infants With Cochlear Implants : A Quantitative Analysis., Lydia Doggett

Electronic Theses and Dissertations

Vocal matching, the ability to imitate phonetic properties of speech, was examined in spontaneous interactions of sixteen dyads of mothers and their hearing-impaired (HI) infants with cochlear implants and age-matched normal-hearing (NH) infants. Mother-infant dyads came to three sessions at three, six, and 12 months post-implantation. Vocal matching was defined as an instance of perceptual and acoustic similarity of vowels and consonants between adjacent maternal and infant utterances. Vocal matching occurred in 25% to 50% of infant and in 17% to 64% of mother vocalizations across dyads. Both mothers and infants in the HI group produced fewer matches as compared …

Modeling Hrtf For Sound Localization In Normal Listeners And Bilateral Cochlear Implant Users, Douglas A. Miller

Electronic Theses and Dissertations

Mathematical models can be very useful for understanding complicated systems and for testing algorithms through simulation that would be difficult or expensive to implement. This dissertation presents a model that attempts to simulate the sound localization performance of persons using bilateral cochlear implants. The expectation is that this model could prove to be a useful tool in developing new signal processing algorithms for neural encoding strategies.

The head related transfer function (HRTF) is a critical component of this model, and in the ideal case, provides the base characteristics of head shadow, torso and pinna effects. This defines the temporal, intensity …

A Model For Electrical Communication Between Cochlear Implants And The Brain, Douglas A. Miller

Electronic Theses and Dissertations

In the last thirty years, cochlear implants have become an invaluable instrument in the treatment of severe-to-profound hearing impairment. An important aspect of research in the continued development of cochlear implants is the in vivo assessment of signal processing algorithms intended to improve perception of speech and other auditory signals. In trying to determine how closely cochlear implant recipients process sound relative to the processing done by a normal auditory system, various assessment techniques have been applied. The most common technique has been measurement of auditory evoked potentials (AEPs), which involves the recording of neural responses to auditory stimulation. Depending …