[Altered visual information processing in anorectic girls--the study on potentials related to the test of attention]

Combined biological and psychological basis of anorexia nervosa, related to increased self-control, low self-esteem and peculiar motivation, makes a synthetic approach still hard to achieve. The presented study assessed cognitive functions in anorectic patients with respect to both neuropsychological (test of attention) and biological (electrophysiology of information processing) approaches, and their reciprocal interrelations as well.

Eleven adolescent anorectic females and 10 control subjects performed the Continuous Attention Test CAT. Parameters of potentials elicited by the visual CAT items were referred to the CAT results.

The anorectic girls were more accurate during CAT performance, revealing a lower index of errors, especially of commissions. On the other hand, they revealed a lower amplitude of the P2 component (correlated with index of commissions) and shortened latency of the frontal N2 component (correlated with a lower index of errors). The groups differed in relations between psychometric and biological parameters referring to the earlier stages of information processing. In the control group, high index of detections was correlated to right-sided P1 and P2 components. In the patient group, correlations linked a lowered index of commissions with right-sided N1 and bilateral P2 amplitudes.

Increased self-control in anorexia nervosa, reflected by lower frequency of needless reactions, is related to alterations in biological visual information processing yet on its early, preconscious stage.