Patients with eating disorders favour immediate gratification and ignore long term negative consequences. These behaviours are reflected in data showing that individuals with anorexia nervosa (AN) have impaired decision-making (DM) ability. This study aimed to investigate DM in individuals with bulimia nervosa (BN) using the Iowa Gambling Task (IGT) and skin conductance responses (SCR).
A total of 26 BN patients and 51 healthy controls were recruited. Participants completed the IGT while
their SCR were recorded. Published data of 29 patients with AN were included as an additional clinical comparison group.
Both of the AN and the BN groups performed poorly in the IGT in comparison with the HC group. The BN patients showed no decrease in SCR relative to the HC group whereas a markedly diminished SCR was seen in the AN group.
Individuals with BN perform poorly on the IGT just like AN patients, but unlike the AN group, people with BN do not show diminished SCR. The divergence between SCR and the IGT performance is not consistent with the Somatic Marker Hypothesis. Impaired DM may be related to personality factors such as obsessive-compulsive traits.
Tchanturia, K., Liao, P., Uher, R., Lawrence, N., Treasure, J., & Campbell, I. C. (2007): An investigation of decision making in anorexia nervosa using the Iowa Gambling Task and skin conductance measurements. Journal of International, Neuropsychological Society13:1-7. Liao, P., Uher R., Lawrence, N., Treasure, J., Schmidt, U., Campbell, I. C., Collier, D. A., & Tchanturia, K. (Submitted). An examination of decision-making ability in bulimia nervosa.
|Schmidt, U., Tchanturia, K., & Liao, P.-C. (2008). A neuropsychological examination of specific and global frontal lobe functions in siblings with and without eating disorders. In Aquém e além do cérebro. Behind and beyond the brain. Proceedings of the 7th Symposium of Fundação Bial. Porto: Fundação Bial.|