Evaluation of Dopamine and AN

Question 1

+/- fMRI studies

Answer 1

fMRI studies have confirmed that dopamine neurons are activated in anorexia nervosa, but it is not clear whether this response is due to the disorder or to its resulting nutritional deficit - does demonstrate involvement of dopamine but cannot establish cause and effect

Question 2

+ Frank - anorexic vs. obese sample

Answer 2

Frank enrolled 21 anorexic and 19 obese female volunteers, as well as 23 healthy controls, and measured the brain’s dopamine centres using scanning techniques. Dopamine centres were averactive in AN women and lethargic in obese ones - validates role of dopamine in restricting eating through anhedonia and repetition of behaviour

Question 3

+ Kaye - PET scans

Answer 3

Kay used PET imaging to assess the activity of brain dopamine receptors and found increased dopamine activity in recovering anorexics - suggests role of dopamine in AN

Question 4

Kaye - dopamine and anxiety

Answer 4

Kaye found that, in people with AN, the release of dopamine in the dorsal striatum triggers anxiety rather than pleasure - supports idea that dop. does not properly function in AN sufferers

Question 5

Antipsychotic drugs

Answer 5

Antipsychotic drugs which target the dopamine system have so far failed to live up to their promise in treating eating disorders - refutes role of dopamine as sole cause

Question 6

Brains of rodents

Answer 6

The brains of starved rodents came to resemble those of anorexics - suggests food consumption leads to reduced dopamine, rather than dopamine being the cause of AN - cause and effect