Eus van Someren

Sleep and Cognition

Our group aims to unravel brain mechanisms underlying insomnia and its adverse consequences for other mental disorder. Insomnia is the second-most prevalent mental disorder and the primary modifiable risk factor for depression, anxiety disorders and PTSD. Surprisingly, circadian and homeostatic sleep regulation seem intact, and sleep deprivation failed as a model for insomnia. The emerging picture is that the risk of developing insomnia involves insufficient processing of emotional distress during restless REM sleep. This insufficiency is likely due to failing silencing of the locus coeruleus which would normally occur only during restful REM sleep. The failure disrupts nocturnal synaptic plasticity in limbic circuits. Non-stop taking tension to the next day, instead of resolving it overnight, could accumulate into the round-the-clock hyperarousal that characterizes insomnia.