R2. Effects of Hearing Loss on Mobility and Participation of People Aging with Vision Disability

Principal Investigator: Carrie Bruce, Ph.D., CCC-SLP
Project Team: Katharina Echt, Ph.D.; Bruce Walker, Ph.D.; Sherri L. Smith, Au.D., Ph.D.
Project Collaborator: Karissa Bedi, M.Ed., COMS, CVRT

Specific Aims
Individuals aging with vision disability, who bear greater comorbidity burden, may experience considerable negative secondary impacts on mobility activity and participation. For individuals with age-related hearing loss (e.g., presbycusis, loss of sound and speech discrimination), negative outcomes can be attributed to diminished effectiveness of sound-based compensatory strategies (e.g., auditory spatial cues) and AT (e.g., sonic canes, talking GPS). This project will investigate the impact of acquired hearing impairment on the effectiveness of sound-based AT devices and strategies as related to mobility activity and participation of individuals aging with vision disability.

Specific aims of this project are to:

  1. understand the proximal impact of age-acquired hearing impairment on usability and satisfaction with mobility-related AT devices and compensatory strategies;
  2. understand the distal impacts on mobility activity and community participation;
  3. identify sound-related characteristics of AT devices (e.g., loudness, frequency) and compensatory strategies (e.g., types and levels of ambient environmental sound) that are linked to mobility performance;
  4. identify salient sound characteristics that can be incorporated into AT to improve usability of devices and effectiveness of mobility strategies; and
  5. develop and validate, evidence-based guidelines for AT design and integrative rehab practices to enhance the effectiveness of AT and compensatory strategies.

Hypotheses
The overarching hypothesis is that reduced auditory capacity due to age-related hearing loss will negatively impact mobility activity of visually impaired older persons by severely constraining options for compensatory device and/or strategy use. Distal impacts of these impairments and compensatory constraints will lead to additional activity limitations and participation restrictions.

H1. (Aim 1) Self-reported usability (i.e., effectiveness, efficiency, satisfaction) and use frequency of AT devices and compensatory strategies will be lower among individuals with vision disability and age-acquired hearing impairment compared to age-matched individuals with vision disability alone.

H2. (Aim 2) Individuals who report lower usability and frequency use of AT devices and compensatory strategies will have greater activity limitations and participation restrictions (measured by Fitbit activity data and life space restriction).

H3. (Aim 3) Actual mobility performance (measured by accuracy and task completion) is associated with usability (effectiveness, efficiency, frequency of use) of sound-based characteristics of AT devices (e.g., loudness, frequency, duration) and compensatory strategies (e.g., types and levels of environmental sound such as ambient noise, auditory cues, acoustic signatures).

H4. (Aim 4) User preferences for sound (measured by loudness level, frequencies, rates, duration, rhythm) will be associated with ability to discriminate sounds and degree, frequency, laterality and symmetry of hearing loss.