Article

Altered insula response to taste stimuli in individuals recovered from restricting-type anorexia nervosa.

Department of Psychiatry, School of Medicine, Western Psychiatric Institute and Clinic, University of Pittsburgh, Pittsburgh, PA 15213, USA.
Neuropsychopharmacology (Impact Factor: 7.83). 03/2008; 33(3):513-23. DOI: 10.1038/sj.npp.1301443
Source: PubMed

ABSTRACT Anorexia nervosa (AN) is an illness characterized by aversion to ingestion of normally palatable foods. We examined whether there is a primary disturbance of taste processing and experience of pleasure using a sucrose/water task in conjunction with functional magnetic resonance imaging (fMRI). To avoid confounding effects of illness, 16 women recovered from restricting-type AN were compared to 16 control women (CW). We used a region of interest-based fMRI approach to test the idea that individuals with AN have differential neural activation in primary and secondary taste cortical regions after sucrose and water administration. Compared to CW, individuals recovered from AN showed a significantly lower neural activation of the insula, including the primary cortical taste region, and ventral and dorsal striatum to both sucrose and water. In addition, insular neural activity correlated with pleasantness ratings for sucrose in CW, but not in AN subjects. Altered taste processing may occur in AN, based on differences in activity in insular-striatal circuits. These data provide the first evidence that individuals with AN process taste stimuli differently than controls, based on differences in neural activation patterns.

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