Auditory Temporal Processes in Aging

This research program in speech perception and auditory psychophysics examines the hypothesis
that many of the predominant difficulties in speech understanding of elderly listeners are
related to underlying problems in auditory temporal processing. One form of degraded speech
that is particularly difficult for elderly listeners to perceive is accented English.
Alterations of speech stress and timing with accent may be viewed as a form of degradation in
temporal aspects of speech prosody, and this type of temporal distortion is the focus of
investigation in the next project period. Moreover, psychoacoustic results demonstrate that
large age-related difficulties in temporal processing exist for the perception of auditory
tempo and rhythmic characteristics of sequential stimulus patterns featuring a stressed tone.
Listener processing difficulty could be attributed to peripheral and/or central processing
mechanisms, as well as various cognitive factors, including the degree of familiarity with
prosodic features of different native languages. The project examines the relative
contribution of peripheral hearing impairment, type of stimulus temporal complexity and
cognitive demand, and the linguistic background experience of listeners on the processing of
temporal prosody cues in speech and non-speech stimulus patterns. The project associated with
this clinical trial examines the efficacy of auditory training paradigms with stimuli that
feature temporal contrasts for improving perception of accented English and non-speech
sequences by older people. The research described in this application seeks to address one
goal outlined by the National Institute on Aging: to develop effective interventions to
maintain health and function and prevent or reduce the burden of age-related diseases,
disorders, and disabilities. The approach in this research program involves (a) an assessment
of the problems encountered in daily activities by the elderly population, (b) an analysis of
specific task demands in relation to individual capabilities, and (c) basic research on
sensory and perceptual changes with age and on the ameliorating effects of emerging
technologies (including rehabilitation). This three-dimensional approach is expected to
further progress toward improving communication and health-related quality of life for senior
citizens.

Inclusion Criteria:

- Age and hearing sensitivity:

- Younger listeners (18-40 years) with normal hearing;

- Older listeners (65-80 years) with normal hearing;

- Older listeners (65-80 years) with bilateral, mild-to-moderate sensorineural hearing
loss.

- High School Diploma,

- native speaker of English (based on self-report)

- normal middle-ear function (based on tympanometry)

- normal cognitive function (based on score on Montreal Cognitive Assessment)

- good-to-excellent word recognition scores (based on Northwestern University Test # 6
word recognition scores presented in quiet at suprathreshold levels).

Exclusion Criteria:

- non-native speaker of English,

- motor and/or speech disorders that prevent participant from providing a time-locked
response,

- presence of middle ear disease or conductive hearing loss,

- presence of severe or profound hearing loss,

- presence of poor word recognition scores,

- cognitive impairment.