The hypothalamus is located in the limbic system and is involved in homeostasis (the way in which an organism maintains a balanced internal environment). In relation to eating behavior, there are different mechanisms which detect the state of the internal environment (e.g. whether the body has enough nutrients) and correct/restore that environment to its optimal state. A decline in glucose levels in the blood activates the lateral hypothalamus (the ‘on’ switch), which causes hunger and leads the person to search for food and eat. This means that glucose levels rise, which then activates the ventromedial hypothalamus (the ‘off’ switch), leading to feelings of satiation (feeling full), so the person stops eating.