The sleep disorder that leads to Parkinson’s

Pierre-Alexandre Bourgouin
PhD Student
Université du Québec à Montréal
At the Université du Québec à Montréal, PhD candidate Pierre-Alexandre Bourgouin studies the connection between a sleep disorder called idiopathic REM behaviour disorder and Parkinson’s disease. Bourgouin, a neuropsychologist, uses an imaging technology to search for changes in the white matter in the brains of people with this disorder, which can cause them to be violent during REM sleep. Since 80 percent of those people later develop Parkinson’s, he hopes to discover differences in their white matter—the connections between cells. Those differences could provide clues to how Parkinson’s develops.

One of the disturbing aspects of having idiopathic REM behaviour disorder is that most people who suffer from it have no idea that during their REM sleep cycles they thrash, kick, punch and otherwise harm their bed partners.

“It’s quite dangerous and often it’s the bed partner who seeks help,” says Pierre-Alexandre Bourgouin, a PhD candidate at the Université du Québec à Montréal. “The patients don’t realize what they do during sleep.”

Bourgouin, a neuropsychologist, is studying another disturbing aspect of this disorder: its connection to Parkinson’s disease. Although idiopathic REM behaviour disorder (iRBD) is relatively rare—less than two percent of the population suffers from it—80 percent of those who do have it later develop Parkinson’s and related disorders.

Bourgouin wants to know why the sleep behaviour disorder leads to Parkinson’s. To find the answers, he’s using an imaging technology called Diffusion Tensor Imaging (DTI) to scan the brains of people with the sleep disorder, searching for clues in their white matter. He’s looking for differences in the white matter, which consists of the axons, or connections, between brain cells, among people with the sleep disorder who also have cognitive impairment and mild motor symptoms of Parkinson’s disease. He’ll compare the images of their white matter to those of people who have the sleep disorder, but don’t have Parkinson’s symptoms.

Ultimately, Bourgouin hopes his discoveries could be used to help diagnose Parkinson’s disease by flagging changes in the brain’s white matter that could predict who will develop Parkinson’s. He’s also anxious to see if he can better understand how Parkinson’s progresses, and provide clues that could help find a treatment to halt the progression or prevent this disease.

“We’re studying people with REM behaviour disorder to better understand how the symptoms start, how they affect the brain, and how they unfold to full-blown Parkinson’s disease,” Bourgouin says.

As a curious child, Bourgouin has always been fascinated with the brain, he says—and that curiosity led him directly into research, where he can try to help people like those struggling with both iRBD and Parkinson’s. Bourgouin is grateful to receive a $35,000 over 2 years funded in partnership with Le Fonds de recherche du Québec — Santé

“In this domain of research, it could really have a clinical impact on the patients and could help people. That’s exciting,” Bourgouin says.

For more information on the Parkinson Research Program, visit