Bistability for audiovisual stimuli: Perceptual decision is modality specific

Area of Science:

• Cognitive Neuroscience
• Psychology
• Sensory Perception

Background:

• Ambiguous stimuli can cause spontaneous perceptual alternations.
• Bistable perception exhibits common temporal dynamics across visual and auditory modalities.
• This raises questions about centralized versus distributed mechanisms in perceptual decision-making.

Purpose of the Study:

• To investigate whether bistable perception is governed by local, stimulus-specific competition or a central, supramodal mechanism.
• To test the distributed versus centralized hypothesis by simultaneously monitoring auditory and visual bistable perception.
• To differentiate between stimulus-similarity interactions and perceptual decision-linked interactions.

Main Methods:

• Observers simultaneously monitored bistable perception of ambiguous auditory (streaming) and visual (plaids or apparent motion) stimuli.
• The study utilized cross-modal presentation to analyze interactions between sensory modalities.
• Temporal dynamics of perceptual switches were analyzed in both unimodal and bimodal conditions.

Main Results:

• The long-term dynamics of bistable perception remained identical across unimodal and bimodal presentations.
• Even strong short-term cross-modal interactions did not alter the dynamics of bistable perception.
• Bistability was observed to co-occur independently in different sensory modalities.

Conclusions:

• The findings support models of distributed competition for perceptual decision and awareness.
• Bistable perception in different sensory modalities can operate independently.
• This suggests that perceptual decision-making is not solely reliant on a single, centralized mechanism.