Information AboutHunger |
| CATEGORIES ABOUT HUNGER | |
| food and drink | |
| motivation | |
| neuropsychology | |
| limbic system | |
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Hunger is a feeling experienced when the Glycogen level of the Liver falls below a threshold, usually followed by a desire to eat. The usually unpleasant feeling originates in the Hypothalamus and is released through receptors in the liver. Although an average nourished human can survive weeks without food intake,1 the sensation of hunger typically begins after several hours without eating. Hunger can also be applied metaphorically to cravings of other sorts, e.g. "hungry for victory." HUNGER PAINS When hunger contractions occur in the Tonus . Periods between contractions increase with old age. SATIETY Satiety, or the feeling of fullness, is the disappearance of hunger after a meal. It is a process mediated by the ventromedial nucleus in the Hypothalamus . It is therefore the "satiety center." Various hormones, first of all Cholecystokinin , have been implicated in conveying the feeling of satiety to the brain. Leptin increases on satiety, while Ghrelin increases when the stomach is empty. Therefore, satiety refers to the psychological feeling of "fullness" or satisfaction rather than to the physical feeling of being engorged, i.e. the feeling of physical fullness after eating a very large meal. Satiety directly influences feelings of Appetite that are generated in the Limbic System , and hunger that is controlled by neurohormones, especially Serotonin in the lateral hypothalamus. BEHAVIORAL RESPONSE Hunger appears to increase activity and movement in many animals - for example an experiment on s with their Cerebral Cortex or stomachs completely removed. Increased activity on Hamster Wheel s occurred when rats were deprived not only of food, but also water or B Vitamins such as Thiamine Guerrant, N.B., Dutcher, R.A. (1940) ''Journal of Nutrition'' 20:589. This response may increase the animal's chance of finding food, though it has also been speculated the reaction relieves pressure on the home population. REFERENCES EXTERNAL LINKS
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