Investigating the role of value in perceptual multistability: a computational and neuroimaging approach

• Applicant: Professor Shervin Safavi, Ph.D.
• Subject Area: Human Cognitive and Systems Neuroscience ; Experimental and Theoretical Network Neuroscience ; Cognitive, Systems and Behavioural Neurobiology
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 550411021

When humans (and some other animals) are exposed to particular forms of ambiguous stimuli (e.g. the Necker cube and binocular rivalry), they experience multiple percepts that switch over time. The existence and dynamics of perceptual switching have been investigated with a diverse range of tools and approaches, and has provided important insights into a wide range of questions in cognitive neuroscience, from core principles of information processing in the brain to aspects of higher cognitive processes such as visual awareness. Prevalent cognitive-, computational- and algorithmic-level accounts of multistable perception start from the seminal idea of analysis by synthesis. This account suggests, as we have a generative model about what we expect to see, and perception is inverting this model. Although this account of perceptual multistability has provided important insights into this phenomenon, it struggles to explain multiple aspects of recent data, both in conventional settings and psychiatric conditions. For instance, when participants in a binocular rivalry experiment are exposed to one image relevant to the task at hand, rivaling with another irrelevant image, they perceive the former image for far longer times than the latter; thus, task relevance can trump pure inferential factors in determining dominance. As the second example, in the frequently used case of rivalry between face and house images, faces enjoy longer dominance. One of the key shortcomings of this account of multistability, is its utility-free nature In the case of face-house rivalry, classical account, treats both stimuli as a target of inference, without taking into account their utility. However, faces in this case, have higher utility compared to houses (because of their special position in our visual diets, aesthetic judgments, and their social relevance). We argue, exactly the value or utility justifies the perceptual privilege of the faces in binocular rivalry. Lastly, various aspects of perceptual multistability (e.g. differences in the rate of perceptual switches) have been found to differ in a wide range of psychiatric conditions (where in most of them decision-making is central). We propose a novel framework, based on Reinforcement Learning, in which perceptual multistability is treated as an active decision process, with perceptual alternation being an action that results from an internal decision-making process. The proposed project has four main objectives: 1. Development of a novel computational model of perceptual multistability that accommodates the key role of value 2. Empirical demonstration of the contribution of multiple sources of value in perceptual multistability and evaluating our computational model 3. Identifying key sub-clinical trans-diagnostic psychiatric traits concerning the role of value in perceptual multistability 4. Identifying the neural substrate of value processing in perceptual multistability through a neuroimaging experiment.

• DFG Programme: Research Grants
• International Connection: Switzerland
• Co-Investigator: Professor Dr. Peter Dayan
• Cooperation Partner: Professor Philipp Sterzer, Ph.D.