Lisa Roux

Université de Bordeaux, CNRS UMR 5297, Interdisciplinary Institute for Neuroscience

Title

Breathing and hippocampal network activity during wake and sleep

Abstract

Brain activity and breathing rate influence each other but it remains unclear how fine respiratory features accompany brain state transitions. By recording nasal pressure and hippocampal activity in freely-moving mice, we detected respiratory pauses nested within breathing cycles. We showed that these pauses are the key components dictating the animal’s respiratory rate and that they strongly impact neuronal networks. Moreover, pause properties discriminated Wake, rapid eye movement (REM) and non-REM (NREM) sleep. We proved that the rules linking respiration and states are generalizable by predicting states based on respiratory features in animals that were not part of our training set. Transient increases in pause durations paralleled the infra-slow oscillations of noradrenaline during NREM, highlighting the classical NREM packets delineated by movement-based micro-arousals and sigma-band power troughs. As pauses after inhalation predicted subtler sigma-band variations, we proposed new packets, based on pauses, structuring NREM in ~30s windows of high sigma power. Overall, our work revealed how respiratory features highlight the macro- and micro-architectures of sleep, suggesting new relationships between brain functions and respiration.

Biosketch

Lisa Roux is a research directorat CNRS leading the team “Neurophysiology of Natural Behaviors” at the Interdisciplinary Institute for Neuroscience (IINS, CNRS UMR5297, Bordeaux University, France) since 2018. She did her PhD under the supervision of C. Giaume at the Collège de France where she worked on neuro-glial interactions in the olfactory system using primarily slice electrophysiology. Her work unraveled a bi-directional loop of interactions between neuron and astrocyte networks which could impact olfactory information processing.In 2012, Lisa Rouxjoinedthe lab of Gyorgy Buzsáki (NYU, USA) as a postdoctoral fellow. There,she used advanced in vivo electrophysiology and optogenetic approaches in freely moving miceto understand the mechanisms of hippocampal oscillations and their function in spatial memory processes. Her work also uncovered the key role played by sharp wave ripple oscillations in the maintenance of the hippocampal “cognitive map” during spatial learning. As an independent group leader at the IINS, she now aims at understanding how the dialog between olfactory and memory networks underlie the formation, consolidation and recall of long-term memory traces. Her teammainly focuses on two paleocorticesimportant for memory function: the hippocampus and the olfactory piriform cortex.