Audiovisual Deficits in Older Adults with Hearing Loss: Biological Evidence

Abstract

Objective:To examine the impact of hearing loss (HL) on audiovisual (AV) processing in the aging population. We hypothesized that agerelated HL would have a pervasive effect on sensory processing, extending beyond the auditory domain. Specifically, we predicted that decreased auditory input to the neural system, in the form of HL over time, would have deleterious effects on multisensory mechanisms. Design:This study compared AV processing between older adults with normal hearing (N ϭ 12) and older adults with mild to moderate sensorineural HL (N ϭ 12). To do this, we recorded cortical evoked potentials that were elicited by watching and listening to recordings of a speaker saying the syllable "bi." Stimuli were presented in three conditions: when hearing the syllable "bi" (auditory), when viewing a person say "bi" (visual), and when seeing and hearing the syllables simultaneously (AV). Presentation level of the auditory stimulus was set to ϩ30 dB SL for each listener to equalize auditory input across groups. Results:In the AV condition, the normal-hearing group showed a clear and consistent decrease in P1 and N1 latencies as well as a reduction in P1 amplitude compared with the sum of the unimodal components (auditory ϩ visual). These integration effects were absent or less consistent in HL participants.Conclusions: Despite controlling for auditory sensation level, visual influence on auditory processing was significantly less pronounced in HL individuals compared with controls, indicating diminished AV integration in this population. These results demonstrate that HL has a deleterious effect on how older adults combine what they see and hear. Although auditory amplification vastly improves the communication abilities in most HLs, the associated atrophy of multisensory mechanisms may contribute to a patient's difficulty in everyday settings. Our findings and related studies emphasize the potential value of multimodal tasks and stimuli in the assessment and rehabilitation of hearing impairments.

Effects of hearing and vision impairments on the Montreal Cognitive Assessment

“…Dupuis et al integration mechanisms in the brain (e.g., van Wassenhove, Grant, & Poeppel, 2005). However, the ability to integrate multisensory information can be reduced in individuals with HL (Musacchia, Arum, Nicol, Garstecki, & Kraus, 2009). In addition, audiovisual stimulus presentation can improve working memory performance for individuals with NH when listening in noise (Pichora-Fuller, 1996) and for individuals with HL when listening in quiet (Brault, Gilbert, Lansing, McCarley, & Kramer, 2010).…”

Audiovisual Asynchrony Detection and Speech Intelligibility in Noise With Moderate to Severe Sensorineural Hearing Impairment

“…What made a difference was the age of the listeners. Elderly listeners in each listener group tended to have longer synchrony windows, which was linked to reduced audiovisual integration observed with the elderly in some studies (Musacchia et al 2009). Because many hearing-impaired listeners are older, our second and opposing expectation would then be a reduced sensitivity to asynchrony in hearing-impaired listeners.…”

Enhanced audio–visual interactions in the auditory cortex of elderly cochlear-implant users

“…This effect is based on the intersensory redundancy and is often referred to as the redundant signals effect (Giard and Peronnet, 1999;Girard et al, 2011;Mahoney et al, 2011;Miller, 1982). Multisensory interactions can be influenced by mild to moderate and extensive hearing loss Musacchia et al, 2009;Puschmann et al, 2014). For instance, congenitally deaf individuals and CI users show less pronounced visuoetactile interactions when compared with NH individuals Landry et al, 2013).…”