Degenerative Consequences of Congenital Deafness

East Carolina University34 enrolled

Overview

In this study, the investigators will study one of the basic biophysical properties of the auditory nerve, charge integration, behaviorally (detection threshold versus phase duration functions). The investigators will compare charge integration in two subject groups: congenitally deafened and deafened at a later age in life. The investigators will then examine if behaviorally estimated neural excitation patterns differ between short phase duration and long phase duration stimulation. Lastly, The investigators will measure if speech recognition improves with using long phase duration stimulation, relative to using the standard default short phase duration stimulation. The primary endpoint of the study is speech recognition, and the secondary endpoints are the steepness of the detection threshold versus phase duration functions, and the width of psychophysically estimated neural excitation.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Congenital Deafness

Interventions

Phase durationBEHAVIORAL

We will vary the phase duration in the stimulation, and examine detection threshold, spatial spread of neural excitation, and speech recognition as the outcomes.

Eligibility

Sex: ALLMin age: 15 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Cochlear Nucleus cochlear implant users or Advanced Bionics cochlear implant users * Native speakers of English * Early onset of deafness (\< 3 years of age); no requirement for age at implantation * Late onset of deafness (\> 3 years of age); matched in duration of deafness to the early onset group * Has had device experience for at least one year * Can be child or adult at the time of enrollment Exclusion Criteria: * None

Outcomes

Primary Outcomes

Slope of the strength duration function

Subjects will be measured for detection thresholds as a function of phase duration of the pulse train and the slope of the function will be derived.

Time frame: starting 6 months post award notice and will take up to 4 years to complete

Secondary Outcomes

Psychophysically estimated neural excitation width

Subjects will be measured for psychophysical forward-masked spatial tuning curves using stimuli with long and short phase duration.

Time frame: starting 6 months post award notice and will take up to 4 years to complete

Speech recognition using long phase duration

Subjects' speech recognition performance will be evaluated using CUNY and TIMIT sentences with long and short phase duration stimulation.

Time frame: starting 6 months post award notice and will take up to 4 years to complete

Degenerative Consequences of Congenital Deafness

Overview

Conditions

Interventions

Eligibility

Locations (1)

Outcomes

Primary Outcomes

Secondary Outcomes