Neuroimaging in anorexia nervosa.

Neuroimaging in anorexia nervosa has revealed morphological and functional alterations, most of which are currently interpreted as consequences of the anorectic state that are reversible, at least partially, after weight gain. Enlargement of CSF spaces, mainly of cortical sulci, is evident on CT and MRI. This reversible shrinkage of brain tissue ("pseudoatrophy") also affects the pituitary gland. A functional imaging study with positron emission tomography (PET) revealed caudate hyperactivity during the anorectic state, and several mild right-left asymmetries possibly related to alterations of mental state (vigilance, depression, etc.) have also been reported in bulimia nervosa. New aspects may be added, when techniques to image functional brain activation during specific tasks and regional receptor binding capacities are used to study anorexia nervosa.