INTRODUCTION
The brain is generally made up of cells which communicate with other parts of the brain and body by endocrine and nervous processes. The types of chemicals (neurotransmitter) released and the amplitude of electrical signals determines the level of output signalled from cell to cell.
The hypothalamus is a small structure about 4g in weight, it is located along the ventral midline of the brain, underneath the thalamus surrounding the third ventricle.
This structure derives from a specialised region of the forebrain during development named the “diencephalon”. It consists of specialised cells grouped into nuclei which have acquired many different functions to help regulate ones internal environment.
The hypothalamus allows the body to respond to the external environment eg. If you’re lying on the beach, hypothalamic nuclei will detect a change in temperature and send outputs to other parts of the Nervous system subsequently causing vasodilation and sweating to occur to allow you to cool down.
It is the hypothalamus along with other connections in the brain which allows your body to respond to the external environment and also detect changes within the internal environment to maintain homeostasis.
The animation above shows the location of the hypothalamus marked in red
Human Brain image courtesy of Wikimedia Commons. This image is in the public domain and thus free of any copyright restrictions.