Research experiences & projects
How memories are stored in the brain? Which brain networks and which cellular and molecular mechanisms are involved in memory formation and its short- or long-term retention? These questions remain largely debate. My research interests are focus on learning and memory, in particular in complex memory, and the modifications of memories across lifetime according to the environmental and physiological conditions, including their influence on precision, forgetting, reinforcement and updating of memories. I am interest in cellular and molecular mechanisms underlying brain plasticity, their role in the formation and the retention of memories and the brain structures within which these changes occur during the laying down of memories. I am also interested in the role of adult hippocampal neurogenesis in these processes, in particular the role of the newborn neurons in the function of pattern separation and sorting out the memories.
December 2019 - February 2022 Neuroscience post-doc researcher
CNES post-doc fellowship
"Impact of microgravity and hypergravity on memory processes"
Supervisor: Dr. Jean-Luc Morel
Institute of neurodegenerative diseases (IMN), CNRS UMR5293, Bordeaux
The causes of cognitive and memory deficits observed in astronauts during spaceflight, or in simulated human or animal microgravity models, remain largely unknown. Several types of cerebral alterations may be at the origine of these deficits, from genes to cerebral connectivity. I have focused on adult neurogenesis. I used a simulated rat microgravity model (hindlimb suspension) which mimics the main physiological effects observed in humans in weightlessness (muscle and bone loss, cardiovascular deconditioning). The results showed an alteration in adult neurogenesis in the hippocampus and subventricular zone, the two main neurogenic niches in the adult brain. I also assessed the effect of a countermeasure, physical exercise. In the simulated microgravity model, we observed compensation on survival loss of new neurons only in the hippocampus.
September 2018 - October 2019 Neuroscience post-doc researcher
"Boosting remote episodic memory in rats"
Supervisor: Dre. Alexandra Veyrac & Dre. Nadine Ravel
Lyon Neuroscience Research centre, INSERM U1028, CNRS UMR5292
In daily life, episodic memories are mainly incidentally acquired without any conscious effort and constitutes a more or less faithful record of individual experiences. This essential property of episodic memory makes it particularly sensitive to forgetting and interferences. I explored different experimental strategies that may boost long term episodic memory retention in rats. For this, we used two different non-invasive strategies: a specific re-expositon to some elements of the episode during the memory consolidation or a memory-modulating event (novelty) presented before the episode experience. I also perform local field potential in vivo recording in several brain areas on rats that behaves during episodic memory to characterize the brain network implied from the encoding to the remote episodic recollection, in direct link with the observed behavior, and to quantify the modifications when remote memory retention is boost, notably the changes in activity, coherence and connectivity within the relevant brain networks.
April 2016 - June 2018 Neuroscience post-doc researcher
"Facilitate memory persistence through consolidation and reconsolidation in early, middle, and late adulthood in rats"
Supervisor: Dre. Szu-Han Wang
Centre for Clinical Brain Sciences, Edinburgh, Scotland
Memory for weak events rarely create an enduring memory, contrary to strong events. However, when environmental novelty is introduced around memory encoding, it can modulate the memory persistence, phenomenon called behavioral tagging and capture (BTC). We hypothesized that the neuronal ensemble activated by the novelty need to share, at least in part, the same neuronal ensemble activated by the memory encoding for BTC to occur. I showed that the neuronal assemblies representing the novelty and the memory encoding had significant overlapping in the hippocampus, in particular in the distal CA1 and proximal CA3. During early normal aging, novelty did not facilitate long-term memory persistence. But, re-exposure to the encoded environment after learning improved memory persistence in middle-aged rats, suggesting a weakened tagging and capture mechanism at an early stage of aging.. At the cellular level, both encoding- and novelty-triggered neuronal populations were significantly reduced with a more profound effect in encoding neurons. Long-term memory decline in late aging, and novelty or memory reactivation enabled memory maintenance during normal aging. Prior training improved cognition through facilitating task performance, strengthening short-terme memory and intermediate memory, and enabling encoding-boosted long-term memory.
October 2015 - March 2016 Neuroscience post-doc researcher
"Role of hippocampal adult neurogenesis in episodic memory"
Supervisors : Dre. Alexandra Veyrac & Dr. Serge Laroche
Neuroscience Paris-Saclay Institute, CNRS UMR9197, Orsay, France
October 2011 - September 2015 Neuroscience PhD fellowship
Ministerial Scholarship and FRM Grant
"Neurogenèse adulte hippocampique : Rôle fonctionnel dans la mémoire épisodique et recrutement des nouveaux neurones lors de la mémorisation"
Supervisors : Dre. Alexandra Veyrac & Dr. Serge Laroche
Neuroscience Paris-Saclay Institute (NeuroPSI), CNRS UMR9197, Orsay, France
I studied the cellular and molecular mechanisms behind episodic memory in rats and in particular the role of adult hippocampal neurogenesis. We used an episodic memory task in rats based on the presentation of occasional episodes. We showed that rats are able to remember on the very long-term brief past episodes of life and to use their episodic memories in a flexible way. Moreover, we characterized profiles of memory retention that allows us to identify individual abilities in the recollection of the various memories elements. Performances of rats subjected to focal irradiation of the hippocampus showed that adult hippocampal neurogenesis contributes significantly to the consolidation and faithful recall of episodic memory, in particular when flexibility is required to remember.
2010 - 2011 (9 months) Internship of Master 2nd year
"Role of the immediate early gene Zif268 in hippocampal adult neurogenesis"
Supervisors : Dre. Alexandra Veyrac & Dr. Serge Laroche
Centre de Neurosciences Paris-Sud, CNRS UMR8195, Orsay, France
I studied the molecular mechanisms underlying the recruitment of newborn hippocampal neurons by learning. For this, we investigated the role of the immediate early gene zif268. We showed that this gene plays a crucial role in the selection and recruitment of newborn hippocampal neurons by spatial learning during their critical period of integration in hippocampal neural networks.
2009 (3 months) Internship of Master 1st year
"Role of the immediate early gene Zif268 in hippocampal adult neurogenesis"
Supervisors : Dre. Alexandra Veyrac & Dr. Serge Laroche
Centre de Neurosciences Paris-Sud, CNRS UMR8195, Orsay, France
