Étude de la relation entre la plasticité de la myéline et le comportement en utilisant l'imagerie par résonance magnétique

 

Christine Tardif

Université McGill

 

Domaine : neurosciences, santé mentale et toxicomanies

Programme Chercheurs-boursiers - Junior 1

Concours 2019-2020

Myelin is a lipid-rich cellular membrane that is wrapped around axons and speeds up the transmission of information across the brain. Brain plasticity has thus far mainly been linked to the dynamic nature of neurons, but new evidence now suggests that myelin plasticity is an additional route by which experience can shape our brain structure and function. Human imaging studies have shown that brain myelination continues after childhood, well into mid-life, and that myelin deficits occur in several mental health disorders, including schizophrenia, autism and anxiety disorders. The link between experience and myelination has gained traction, yet we still have limited insight into whether myelin plasticity causes changes in behaviour or is a secondary effect.

Mice can be used to study the causal relationship between risk factors (e.g. genes or early life experiences), myelin plasticity and behaviour. However an animal that is more similar to the human is necessary to relate myelin plasticity to more complex cognitive functions and behaviours. The common marmoset is a small monkey that shows human-like social interactions supported by a more developed brain. I propose to study the spatio-temporal dynamics of myelination and their relationship to brain function and behaviour in mice, marmosets and humans. To achieve this goal, I will develop and use magnetic resonance imaging techniques to non-invasively measure myelination of the brain.

This research program will make significant contributions to our understanding of the dynamic relationship between myelin plasticity and behaviour, and lead to the design of improved therapies that harness myelin plasticity (using psychological or pharmaceutical therapies) to enhance resilience in people at risk for or diagnosed with a mental health disorder. The brain imaging tools developed in my proposed research program can be used to monitor the impact of future therapies as well.