Sleep therapy

Sleepwalkers in the lab

Parasomnias—such as somnambulism, sleep paralysis and behavioural disturbances in paradoxical sleep—are phenomena that continue to captivate the general public. However, little information about them is available. At most only a few researchers have bothered to measure the electrophysiological and neurological parameters of subjects during their “parasomniac” episodes. But no one has ever succeeded in clearly defining the mechanisms of the dissociated states that are often observed during these episodes.

Tomoka Takeuchi’s objective is to follow the various threads in this fabric in order to clarify the physiological and neurocognitive conditions that govern the appearance of dissociated states, which may be seen as predisposing factors of parasomnia. In her research, she will experimentally trigger various forms of dissociated states by waking up subjects during non-rapid eye movement sleep and when falling into paradoxical sleep. She will work with two groups: subjects suffering from frequent parasomnia, and a control group paired by age. Her hypothesis is that dissociated states will appear more often in people presenting frequent parasomnia.

The subjects will spend five consecutive nights in the laboratory. The first two will be for adaptation. During the next two—the actual experimental nights—the sleep interruption technique (SIT) will be used to trigger the dissociated states. The frequency of dissociated sleep stages, caused by sleep interruption, will then be compared for the two groups.

With her measurements, Ms. Takeuchi hopes to be able to formulate a relevant model of high-risk factors that will be able to predict the occurrence of parasomnia in clinical and preventive contexts.