Project description
A new path to study consciousness
When people experience thoughts, emotions or perceptions, they are aware of their consciousness. However, scientists still do not fully understand how consciousness works. Current research in the field attempts to investigate perceptual consciousness by studying brain response to a stimulus in both conscious and unconscious individuals. To report stimulus awareness, the participants need to make decisions. The EU-funded LEAP project will explore whether a mechanism behind decision-making – evidence accumulation – can help uncover how perceptual consciousness unfolds over time. To achieve this goal, a new computational model of latent evidence accumulation process will be developed and tested using behavioural measures. By combining this model with advanced electrophysiology techniques, the project aims to reveal how neuronal activity controls and guides perception.
Objective
How we consciously experience the world remains a mystery in science. To tackle this problem, scientific works on perceptual consciousness contrast brain activity when participants consciously perceive a stimulus versus when they are unaware of it. To report stimulus awareness, participants need to make decisions. However, the extent to which the well-studied mechanisms of decision-making apply to consciousness is unclear. One possible reason is that standard neuroimaging methods lack the sensitivity to observe whether the mechanisms of decision-making also operate in the absence of task relevance, as when participants become conscious of a stimulus irrespective of any task.
In this project, I will test the hypothesis that a mechanism of decision-making –evidence accumulation– explains how perceptual consciousness unfolds over time. First, I will develop a computational model of a latent evidence accumulation process (LEAP) and test it on behavioral measures of phenomenal aspects of perceptual experience: its duration and intensity. Second, I will search for single neuron activity in humans that instantiates evidence accumulation and test whether it also determines these phenomenal aspects of perceptual experience. Third, I will stimulate the corresponding brain regions to disentangle their causal role in either solely triggering perceptual experience or shaping it. Last, I will use the LEAP model to explain hallucinatory-like experiences in patients with Parkinson's disease and test whether deep-brain stimulation affects only decision-making –as previously shown– or also perceptual experience.
By combining computational modeling and cutting-edge electrophysiology, the LEAP project will provide unique mechanistic insights on how neuronal activity determines perceptual experience and guides its temporal dynamics. It will also provide a tool to better understand hallucinations, which remain today a major debilitating symptom in numerous psychiatric disorders.
Fields of science
Keywords
Programme(s)
- HORIZON.1.1 - European Research Council (ERC) Main Programme
Topic(s)
Funding Scheme
HORIZON-ERC - HORIZON ERC GrantsHost institution
75654 Paris
France