The goal of this observational study is to investigate concussions and contact sports practices in REM sleep behaviour disorder (RBD).
The main questions it aims to answer are:
* What is the proportion of patients with RBD that have a history of concussions or exposure to contact sports?
* Is this proportion higher to that in control patients without a diagnosis of RBD?
Participants will undergo an interview with a sleep medicine specialist to answer questions about history of concussions and contact sports practices.
Researchers will compare an RBD group and a control group (without RBD) to see if the proportion of concussions and exposure to contact sports differ.