The Eating Disorders (ED) of Anorexia Nervosa (AN) and Bulimia Nervosa (BN) are two psychiatric disorders characterised similarly by abnormal feeding behaviours whose aetiology currently remains undiscovered. As outlined by the DSM-IV (1994), AN is distinguished as the refusal by an individual to maintain body weight at or above the normal minimum weight for their age and height. Further characteristics include an extreme fear of becoming overweight and a disturbance in the way the individual perceives their body. There are two types of anorexia nervosa; restricting type (loss of weight only through dieting) and Bing-eating/Purging type (person engages in binge eating behaviour and purging e.g. vomiting or misuse of laxatives). Also from the DSM-IV, BN is …show more content…
(2011) reinforced the amygdala’s (in particular the right side) role in the processing of emotions as a function of its strong interconnectivity in relation to other structures of the ventral system. Specifically they found that in anorexic patients an increase in the activation of the amygdala alongside a decrease in activity of the cingulate cortex could possible result in a negative feedback loop; this loop is thought to comprise the feelings of fullness an AN individual will experience whether or not they have eaten. Similarly hyper-activity of the amygdala has been observed in BN patients although not as high as in AN in an fMRI study where when AN and BN patients viewed pictures of healthily weighted individuals and their own bodies (Vocks et al. 2010). Interestingly, in the same study by Vock et al. (2010), they also interpreted amygdala activation as possibly relating to a form of body-avoidance behaviour that is; they viewed their bodies as a threatening stimulus perhaps because they felt it was unattractive. Although all these regions tend to display abnormal function in ED patients, it appears the some specific ones have a more pivotal or direct