Executive functioning and spatial processing in anorexia nervosa: an experimental study and its significance for the allocentric lock theory.

PURPOSE

The allocentric lock theory (ALT) suggests that people with eating disorders have difficulties in multisensory integration in two reference frames-egocentric and allocentric, whereby the egocentric, but not allocentric, is impaired. This leads to a distorted body image that contributes to the development and maintenance of the disorder. The current study aimed to explore a facet of the ALT, namely, the visuo-spatial aspect, and its relation to cognitive flexibility in patients with anorexia nervosa (AN).

METHODS

Fifty-five participants took part in the study: 20 AN patients and 35 controls, matched by age and education. The object perspective taking test (OPTT) and the mental rotation test (MRT), tapping egocentric and allocentric representations, respectively, and a set-shifting task were administered. The brief symptom inventory was used to measure overall levels of distress.

RESULTS

AN patients showed higher level of distress. They performed poorer on the OPTT and set-shifting task but not on the MRT. The OPTT and MRT were correlated for controls but not for AN patients, while the set-shifting task and body mass index were associated with the OPTT but not with the MRT for the AN patients.

CONCLUSIONS

The findings support the ALT by demonstrating impaired visual egocentric representations and intact allocentric visual functions in AN patients, with cognitive flexibility associated only with the egocentric frame. Therefore, egocentric frame impairment in AN patients may be influenced by visual perception and cognitive flexibility deficiency.

LEVEL OF EVIDENCE

Level III: case-control analytic study.