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Introduction

Biological Explanations for Eating Behaviour The first study into eating behaviours was Canon and Wasburn (1912) they conducted a study in which the stomach would contract to indicate hunger and satiety. This research tells us that the strength of the gastric contraction correlated with the hunger and satiety of the participant. The participant was requested to push a button to indicate when they felt hungry. This shows that when we are hungry our brain sends signals to the stomach so that it can contract. A limitation of the study is that it contained one participant so it cannot be generalised. The part of the brain which receives signals of satiety is called the Ventromedial Hypothalamus it is located in the Hypothalamus and controls the amount we eat. ...read more.

Middle

The hormone that is involved in signalling satiety is Cholecystokinin CCK which is the hormone released due to presence of food and sends signals to the VH to indicate satiety. CCK works when food passes from the duodenum, CCK is then released which signals satiety to the brain. A study into CCK is Smith, Gibbs & Kulkosky they injected CCK in animals and humans they found that it lead to a decrease in human size it also sends signals of satiety to the brain. Absence of CCK leads to obesity. A limitation of this study would be ethical issues with the rats well being as the study holds strong forms of animal cruelty. ...read more.

Conclusion

Cummings investigated changes in blood Ghrelin over time between meals. 6 pps were allowed to eat lunch then Ghrelin samples were taken every five minutes from a tube inserted into the vein until the pps requested their evening meal. 5 of the 6 pps Ghrelin levels were closely correlated with the degree of hunger reported by the pps. They researchers concluded that Ghrelin levels notify stomach emptiness and are closely related to subjective feelings of hunger. Limitations of this study is that the data was correlation, so we cannot say that Ghrelin causes feelings of hunger also the all the pps were male therefore there's problems generalising results to the wider population in general and to females. The hormone involved in regulating body weight is called Leptin which is released from adipose to indicate body weight and reduce food intake. ...read more.

This student written piece of work is one of many that can be found in our AS and A Level Physiological Psychology section.