The impact of attentional demands on audiovisual integration depends on task-specific components

Research investigating how attentional demands impacts audiovisual (AV) integration has used a variety of multisensory tasks and procedures to manipulate attentional demands, leading to very differing results. Also, the secondary tasks used to increase attentional demands draw on the sensory modalities already being investigated; for example, a visual distracter task may be used to increase attentional demands in an audiovisual integration task. It is therefore not clear whether the additional task interfered with sensory processing or with audiovisual integration. We used a Colavita task where participants are asked to report the modality of auditory, visual, and audiovisual stimuli to investigate whether increasing attentional demands would impact audiovisual integration. In Experiments 1 and 2, we used a concurrent foot-tapping task to show that increasing attentional demands by having participants completing a secondary task in a different modality interfered with sensory processing but did not affect audiovisual integration. In Experiments 3 and 4, we manipulated attentional demands by having participants respond to all stimuli or only to target stimuli and showed that audiovisual integration was only impacted when targets were infrequent: When participants responded to specific targets amongst five different distracters, they no longer produced more "visual-only" responses than "auditory-only" responses. Whether attentional demands can impact audiovisual integration does not seem unitary and instead seems to depend on task-specific components. (PsycInfo Database Record (c) 2023 APA, all rights reserved).