The hypothalamus is located just under the thalamus, right above the brain stem and it is one of the most important parts of the human brain. Even though it’s very small (barely passes over the size of a peanut at the full developed adults), the hypothalamus must be understood as a path between the nervous system and the endocrine system.
What is this brain portion responsible for?
Basically, it creates and delivers certain neurohormones, which in their turn, control the temperature of the human body, the thirst sensation as well as the energy levels and the sleep needs. Due to these factors, it’s safe to assume that it’s responsible as well, or at least has a big role in keeping the homeostasis of the body, fact that is quite accurate actually.
Not only the humans have this brain part. All the vertebrates have it, and obviously, it’s a highly important part of the nervous system.
It responds to different stimuli such as brightness, smells, pheromones, pituitary homones, stress and different kind of information sent to the brain by the reproductive system, the digestive system and by the vascular system.
Basically, the hypothalamus is the brain part responsible for keeping the body temperature to 36,8-37 Celsius Degrees, but also for the setting the circadiam rhythms (in other words, the sleep hours). It can also stimulate or inhibit, with the help of the neurohormones the activity of the pituitary gland. This happens because these 2 brain parts are connected by the median eminence via a small tube named pituitary stalk. So, the hypothalamus can stimulate or inhibit the secretion of hormones like the growth hormone, prolactin, the luteinizing and the thyroid-stimulating hormone. It can also react over ACTH, betaendorphins and itermedins.