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Perceived size change induced by audiovisual temporal delays
Philip Jaekl1, Salvador Soto-Faraco, Laurence R Harris
1Departament de Tecnologies de la Informació i les Comunicacions, Grup de Recerca Neurociencia Cognitiva Universtitat Pompeu Fabra, Barcelona, Spain. phil.jaekl@upf.edu
Experimental Brain Research
|November 23, 2011
Summary
Audio-visual timing cues influence perceived object size by altering distance perception. Slight delays in sound arrival (up to 100 ms) made objects appear larger, revealing multisensory integration in visual perception.
Area of Science:
- Visual Perception
- Auditory Perception
- Multisensory Integration
Background:
- Visual object size perception relies on extraretinal cues, particularly distance information.
- Audiovisual asynchrony is a reliable but underutilized cue for distance perception.
Purpose of the Study:
- To investigate if audiovisual asynchronies can alter perceived object size.
- To determine if perceived size shifts are mediated by changes in perceived distance.
Main Methods:
- Participants matched the perceived size of a visual target (circle) presented with asynchronous audio to a probe stimulus.
- The timing of the audio stimulus relative to the visual stimulus was systematically varied.
Main Results:
- Perceived visual size increased when sound onset lagged visual onset by up to 100 ms.
- No significant size shifts were observed for longer delays or when sound led visual onset.
- This effect was attributed to audiovisual timing influencing the size-distance relationship.
Conclusions:
- Audiovisual timing provides a novel cue for distance perception, impacting visual size perception.
- The visual system dynamically integrates temporal information from different senses to construct a coherent perception of space and object properties.
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