Everyone has experienced the behavioural changes during the daily shift from wakefulness to sleep (further info). Sleep let us recover from the energy consuming state of wakefulness and supports our brain in memory formation. High arousal, for instance, lets us appreciate a musical concert or prepares us for novel tasks in our job. However, it may also let us worry about uncertainties or tricky things in life. Everybody has indeed felt a little anxious at one time or another. It may have been when we were dealing with issues of work, school, or relationships, or more specific, when we were afraid of heights, closed spaces, or spiders. It is indeed very rare to meet someone who is genuinely without any fear (indicating that fear reactions are important in that they prevent us from encounters that may be harmful or dangerous! Further info). However, fear reactions may escape control, leading to states of excessive and prolonged anxiety (an anxiety disorder; further info), which make life miserable. Impaired regulation of sleep/wake states (further info) affect millions of people and may appear as insomnia but also as a state of dramatically reduced consciousness. Scientists of the Institute of Physiology I aim at the identification of the molecular regulators and neurocircuitries that are involved in the control of the sleep/wake cycle and in the control of fear and anxiety, and they identify mechanisms leading to clinically relevant dysfunctions. In addition, recent effort is directed to specific signalling mechanisms between the two major types of cells in the brain, nerve and glia cells. The Institute provides an excellent, interdisciplinary infrastructure, including laboratories of molecular biology, electrophysiology, optogenetics, and functional microscopical imaging, and a broad spectrum of model systems, including genetic rat and mouse models. Research is embedded into interdisciplinary collaborative research centers on fear, anxiety, anxiety disorders and multiple sclerosis.