Investigating the role of rest on our ability to consolidate our memories.
Is it truly possible to learn while at rest? Delving into the intricate mechanisms of the brain and applying engineering principles, Kathleen Jacquerie centered her Ph.D. thesis on the notion that, contrary to common belief, periods of rest could enhance our memory consolidation. Under the supervision of Guillaume Drion from the Neuromorphic Engineering Laboratory at ULiège, she navigated at the intersection of neuroscience and engineering to shed light on the benefits associated with periods of rest.
T
he human brain, an organ as complex as it is mysterious, goes through various states throughout the day. When it is in learning mode, the activity of our brain is markedly different from that observed when it is at rest. This transition occurs at the level of neurons, the fundamental building blocks of the brain. Neurons have the unique ability to change their connections - called synapses - and it is precisely through these connections that our memories take shape. Imagine that every new piece of information you learn creates a constellation of connections between your neurons. At first sight, you might think that intensive, continuous learning is the key to engraving information in our memory. But what about rest periods? Would they be conducive to strengthening our ability to memorise? This is the hypothesis put forward by Kathleen Jacquerie, a doctorate in engineering science from the Université de Liège who is currently doing a post-doctorate in the laboratory run by Eve Marder, a world-renowned neurobiologist, at Brandeis University (USA).
"As part of my research work, I wanted to propose an innovative approach, computational neuroscience, which combines neuroscience and engineering to unravel the intimate workings of the brain. This discipline, known as neuromorphic engineering, draws its inspiration from brain mechanisms, neurons, and synapses to create more efficient and energy-saving electronic components. To do this, it is crucial to master the workings of biological neurons and memory. Neuromorphic engineering enabled me to design equations capable of reproducing the activity of our neurons," continues the researcher. With my computer's help, I could simulate different states of neuronal activity. On the one hand, the 'tonic' mode is associated with learning, where neurons react to external stimuli by generating action potentials. On the other hand, the 'burst' mode, during periods of rest, where the neurons are disconnected from external stimuli but nevertheless activate strongly collectively, followed by a silent phase". These simulations revealed the evolution of neuronal connections during these state transitions. The results of this research have led to the creation of a novel model of memory consolidation, based on the 'bursts' generated by neurons during periods of rest. This computer model represents a valuable tool for furthering our understanding of memory mechanisms.
These results, which highlight the transitions between the 'tonic' and 'burst' modes of neurons, pave the way for the design of electronic neurons capable of reproducing these two states. Loris Mendolia, a doctoral student in the Neuromorphic Engineering Laboratory at the University of Liège, is currently working on this by developing an electronic component capable of mimicking these modes. "Eventually, the equations formulated by our research could be integrated into these components, opening the door to the creation of electronic devices capable of storing memory by drawing inspiration from our memory mechanisms," enthuses the young researcher.
These results also mark a step forward in our understanding of human memory. On the one hand, Kathleen is offering complementary support for experimental research. Secondly, her project opens up prospects for the development of innovative technologies inspired by our brains. This work illustrates an example of research resulting from the intersection between neuroscience and engineering, where mind and machine meet to push back the limits of our knowledge.
Currently a Postdoctoral Fellow in Boston, Kathleen Jacquerie is studying the impact of global warming on the nervous system and has swapped her computer and models for a microscope and crabs.
About Kathleen Jacquerie
Kathleen Jacquerie's academic career bears witness to her burning passion for understanding brain mechanisms while applying engineering principles. A graduate in Engineering Sciences from the University of Liège, her final year thesis (under the supervision of Professor Guillaume Drion) focused on the modelling of thalamic neurons, renowned for their transitions between wakefulness and sleep.
After a research placement at Cambridge University under the supervision of Timothy O'Leary and Rodolphe Sepulchre, where she acquired additional skills in neural modelling, she did her exchange semester in neuro-engineering at the Technical University of Munich (TUM).
Back in Liège, she was awarded an F.R.S.-FNRS fellowship to do her doctorate, still in the field of neuroscience, on the modelling of memory consolidation as a function of brain state. With her doctorate in hand, Kathleen Jacquerie moved to Boston to undertake a postdoctorate in the laboratory directed by Eve Marder. Her research focused on exploring the impact of global warming on the nervous system, combining her passion for neuroscience with her deep commitment to societal challenges. By using the crab's nervous system, she has direct access to neurons, nerves, and muscles, offering a unique opportunity to unveil fundamental neuronal principles. It is notable that her project has been selected by three prestigious bodies: BAEF, Fulbright and WBI, demonstrating the growing recognition given to work that combines the fundamentals of engineering with an understanding of the brain.
