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Atilgan, H.

Publications and source records attributed to Atilgan, H..

2 recordsLinked to original sources

Training listeners to detect auditory-visual temporal coherence enhances their ability to exploit visual information for auditory scene analysis

The ability to use temporal relationships between cross-modal cues facilitates perception and behavior. Previously we observed that temporally correlated changes in the size of a visual stimulus and the intensity in an auditory stimulus influenced the ability of listeners to perform an auditory selective attention task (Maddox et al., 2015). In this task participants detected timbral changes in a target sound while ignoring those in a simultaneously presented masker. When the visual stimulus was temporally coherent with the target sound, performance was significantly better than when it was temporally coherent with the masker sound, despite the visual stimulus conveying no task-relevant information. Here, we trained observers to detect audiovisual temporal coherence and asked whether this improved their ability to benefit from visual cues during the auditory selective attention task. We observed these listeners improved performance in the auditory selective attention task and changed the way in which they benefited from a visual stimulus: after training performance was better when the visual stimulus was temporally coherent with either the target or the masker stream, relative to the condition in which the visual stimulus was coherent with neither auditory stream. A second group which trained to discriminate modulation rate differences between temporally coherent audiovisual streams improved task performance, but did not change the way in which they used visual information. A control group did not change their performance between pretest and post-test. These results provide insights into how crossmodal experience may optimize multisensory integration.

neuroscience

Integration of visual information in auditory cortex promotes auditory scene analysis through multisensory binding

How and where in the brain audio-visual signals are bound to create multimodal objects remains unknown. One hypothesis is that temporal coherence between dynamic multisensory signals provides a mechanism for binding stimulus features across sensory modalities. Here we report that when the luminance of a visual stimulus is temporally coherent with the amplitude fluctuations of one sound in a mixture, the representation of that sound is enhanced in auditory cortex. Critically, this enhancement extends to include both binding and non-binding features of the sound. We demonstrate that visual information conveyed from visual cortex, via the phase of the local field potential, and is combined with auditory information within auditory cortex. These data provide evidence that early cross-sensory binding provides a bottom-up mechanism for the formation of cross-sensory objects and that one role for multisensory binding in auditory cortex is to support auditory scene analysis.

neuroscience