You may have experienced sleepless nights when you were anxious, stressed or too excited. Such emotions are well-known to affect wakefulness and can even cause insomnia, though the underlying mechanisms in our brain have still been unclear. Scientists in the Sleep Institute in Japan spotted neurons that play crucial roles in connecting emotions and sleep, shedding light on the future discovery of drug targets for anxiety disorder and/or sleep disorders. Encountering predators, adapting to a novel environment or expecting a reward ― these stressful or emotionally-salient situations require animals to shift their behavior to a vigilant state, altering their physiological conditions through modulation of autonomic and endocrine functions. The bed nucleus of the stria terminalis (BNST) is a part of the extended amygdala, which is generally considered as a key player in stress response, fear and anxiety. Through projections to various brain regions including relay nuclei of the autonomic nervous system, hypothalamic regions and the central nucleus of the amygdala, the BNST controls endocrine and autonomic reactions in response to emotionally-salient stimuli, along with behavioral expression of anxiety and fear.