Perception of Speech in Context by Listeners With Healthy and Impaired Hearing

About This Study

Recognition of speech sounds is accomplished through the use of adjacent sounds in time, in what is termed acoustic context. The frequency and temporal properties of these contextual sounds play a large role in recognition of human speech. Historically, most research on both speech perception and sound perception in general examine sounds out-of-context, or presented individually. Further, these studies have been conducted independently of each other with little connection across labs, across sounds, etc. These approaches slow the progress in understanding how listeners with hearing difficulties use context to recognize speech and how their hearing aids and/or cochlear implants might be modified to improve their perception. This research has three main goals. First, the investigators predict that performance in speech sound recognition experiments will be related when testing the same speech frequencies or the same moments in time, but that performance will not be related in further comparisons across speech frequencies or at different moments in time. Second, the investigators predict that adding background noise will make this contextual speech perception more difficult, and that these difficulties will be more severe for listeners with hearing loss. Third, the investigators predict that cochlear implant users will also use surrounding sounds in their speech recognition, but with key differences than healthy-hearing listeners owing to the sound processing done by their implants. In tandem with these goals, the investigators will use computer models to simulate how neurons respond to speech sounds individually and when surrounded by other sounds.

What's Involved

Conditions Studied

Study Locations

Eligibility

Inclusion Criteria:

* Be able to recognize spoken words in English
* Be a competent speaker of north American English
* Be an adult between the age of 18 to 65 years
* Have normal audiometric thresholds below 25 decibels hearing loss (dB HL) at frequencies between 250 and 8000 Hz OR have audiometric thresholds not exceeding 40 dB HL at frequencies between 250 and 8000 Hz OR have audiometric thresholds not exceeding 55 dB HL at frequencies between 250 and 8000 Hz OR use a cochlear implant
* Lack language-learning or other cognitive disabilities

Exclusion Criteria:

* Inability to recognize spoken words in English
* Not a competent speaker of north American English
* Be younger than 18 years of age
* Be older than 65 years of age
* Have normal audiometric thresholds exceeding 25 dB HL at frequencies between 250 and 8000 Hz OR have audiometric thresholds exceeding 40 dB HL at frequencies between 250 and 8000 Hz OR have audiometric thresholds exceeding 55 dB HL at frequencies between 250 and 8000 Hz
* Language-learning or other cognitive disabilities