member

Research work

In our modern societies which value productivity, sleep is often perceived as a loss of time, as if sleep ‘stole’ from us precious hours that we could spend ‘living’. Yet sleep disturbances are a core symptom of numerous societal health issues such as aging, depression, Parkinson’s disease, or Alzheimer’s disease, suggesting that sleep has a crucial role for our global functioning. But the exact functions of sleep and underlying mechanisms remain poorly understood. My overarching goal is to discover what happens to us when we sleep, at the brain, cognitive, and experiential level. Is our stream of consciousness different across vigilance states? Does sleep transform the way we think and act while awake? Answering those questions is challenging because what happens in the sleeping mind is virtually inaccessible. This means that it is difficult to tease apart and measure one specific sleep-related cognitive process by relying solely on EEG activity. I attempt to circumvent this difficulty by combining different strategies:

• traditional indirect methods such as experience sampling (e.g. dream report) and behavioral measurements in cognitive tasks
• neuroimaging (fMRI, EEG) and advanced machine learning tools
• innovative approaches in cognitive research (gesture recognition algorithm, graph theory for semantic networks, targeted memory reactivation)
• clinical populations whose unique sleep peculiarities open a window into the sleeping mind: lucid dreamers who can signal in real-time that they are dreaming and sometimes control their dream scenario during rapid-eye-movement (REM) sleep, and sleepwalkers whose overt behaviors allow to visualize ongoing cognitive processes happening during non-REM sleep.

I use these strategies to investigate how sleep impacts major cognitive functions such as memory, creative problem solving, and perception. More specifically, my project is articulated in three main axes whose specific aims are:

1. To uncover the contribution of sleep memory reactivation in the evolution of a motor learning between encoding and recall, both at the brain and behavioral level.
2. To shed light on the sleep-dependent mechanisms associated with creative problem solving.
3. To better understand how auditory stimuli are processed across vigilance states at the brain and subjective level.

Overall, my project proposes to overcome traditional difficulties stalling research on dreams and sleep functions, -namely the lack of access and experimental control over mental and cognitive processes happening during sleep. It will help deciphering how sleep shapes our wake experiences. In a context where the standard sleep scoring criteria start to be called into question, I hope that my work will help discovering the ‘laws of sleep’, that is the minimal core determinants necessary to define sleep and account for the diversity of dissociated states between wakefulness and sleep that have been described so far. Interests : sleep; dream; memory; creativity; cognition