March 14, 2025 – World Sleep Day
We spend around a third of our lives asleep. The quantity of sleep, its quality, and the timing of our sleep-wake cycles change over the course of our lives. But what doesn’t change is the importance of these cycles for our health in general, and our mental health in particular. In the past year, Douglas research teams have made important discoveries about the links between sleep-wake cycles and mental health.
Prof. Reut Gruber works on sleep in children and adolescents. Over the past year, she has focused on suicidal ideation in young people and its potential link to sleep disturbances. According to Prof. Gruber, “Suicidal ideation in community adolescents without a psychiatric diagnosis is associated with increased daytime sleepiness and later wake-up times,” which is why we need to be vigilant about teen sleep and not neglect good sleep hygiene.
Later in life, sleep-wake cycles can be a good indicator of various mental health disorders, including mood disorders. Prof. Florian Storch investigates the links between sleep-wake cycles and bipolar disorder, using small animals as a study model to better understand the changes in the brain that may contribute to bipolar symptoms.
We recently showed, using mice as a model, that sleep timing comes under control of a second brain clock in patients with bipolar disorder: their sleep-wake cycle is no longer in line with the solar day environment but drifts due to the awakening of this second clock which is not operational in unaffected people.
– Prof. Florian Storch
Thus, in individuals living with bipolar disorder, the cyclical phases of mania and depression often lasting 48 hours could be explained by this second biological clock.
Prof. Diane Boivin is interested in the links between sleep and mood disorders, and has conducted recent literature reviews in collaboration with Dr. Christophe Moderie. “Up to 25% of people suffering from depression are also affected by excessive sleepiness, complicating their treatment. Our literature review enables us to identify various mechanisms underlying this phenomenon and to propose diagnostic approaches as well as targeted treatments, including pharmacological therapies, light therapy and cognitive-behavioral approaches.”
With the onset of menopause, many women report sleep-related problems. Pr. Boivin has focused on these changing sleep-wake cycles to identify possible links between sleep and menopause:
Our recent studies indicate that a weakening of the rhythms controlled by the biological clock would contribute to sleep disturbances in menopausal women, an observation that paves the way for new therapeutic avenues.
– Prof. Diane Boivin
In the near future, we may be able to treat this menopausal symptom more effectively, to ease this often difficult transition of life.
Finally, Prof. Judes Poirier, an expert in the study of Alzheimer’s disease, recently published research on studying sleep as a method of detecting the risk of Alzheimer’s disease:
We have recently discovered that certain biochemical markers of inflammation play an important role in sleep disturbances that significantly increase the risk of developing Alzheimer’s disease after the age of 65.
– Prof. Judes Poirier
Together, these researchers’ work highlights the importance of sleep at all stages of life.
To find out more, visit the theme group page :
“Sleep and Biological Rhythms”