Suppression of audiovisual integration to facilitate covert attention: implications for cochlear implant users

Poster Session F - Tuesday, April 16, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Cailey Salagovic¹ (csalagov@uwo.ca), Catherine Lin¹, Valerie Ah-Yen¹, Ryan Stevenson¹, Blake Butler¹; ¹University of Western Ontario

Flexibly processing and attending to sensory information is crucial for navigating complex environments. Multisensory integration aids in these processes by combining complementary signals into highly salient multisensory percepts. Stimuli can also be selectively ignored or attended, further facilitating efficient processing. Spoken language is an example of a multisensory signal, consisting of auditory information and complementary visual cues produced by articulators. Here, we present two experiments that examined the impact of multisensory integration on speech processing in cochlear implant (CI) users, for whom the spatial and frequency content of speech is significantly degraded. In experiment one, sentences were presented at various audiovisual offsets and intelligibility was assessed. Across both CI users and typically hearing listeners, intelligibility was greatest for near-synchronous audiovisual stimuli. However, at large asynchronies (i.e., beyond the bounds of what is physiologically possible), only typically-hearing listeners appeared to ignore misaligned visual cues and focus on auditory information. To further examine how the relative salience of auditory and visual cues affect a listener’s ability to attend to or ignore multisensory speech, participants in experiment two listened to simultaneous but spatially distinct streams of audiovisual and audio-only speech while listening monaurally (i.e., in the absence of robust spatial cues). Initial results suggest that during monaural listening, visual cues are more salient and less easily ignored than in the binaural condition. Combined, these results suggest the reduction in spatial cues provided to CI users may render them less likely to disengage from visual speech cues, even when they no longer support intelligibility.

Topic Area: ATTENTION: Multisensory