The hypothalamus controls some metabolic processes and autonomic responses via its sympathetic and parasympathetic centres. It synthesises and secretes releasing hormones which stimulate the pituitary to release hormonesThe hypothalamus controls hunger, thirst, body temperature, some aspects of parenting and attachment behaviours, aggression, fatigue, sleep, and circadian rhythms (the body clock).The hypothalamus has a rich blood supply and monitor the blood glucose concentration and water potential of the blood.