The undue influence of shape and weight on self-evaluation in anorexia nervosa, bulimia nervosa and restrained eaters: a combined ERP and behavioral study.

BACKGROUND: Current theories and nosology assume that the self-evaluation (SE) of individuals with eating disorders (EDs) is unduly influenced by body shape and weight. However, experimental data supporting this link are scarce, and it is not specified which subdomains of SE might be affected. METHOD: We studied patients with anorexia nervosa (AN), bulimia nervosa (BN) and healthy controls (HC) with an affective priming (AP) procedure (Study 1) to unveil explicit and implicit associations between shape/weight and SE. We used weight/shape-related prime sentences, complemented by affectively congruent and incongruent target words from two SE domains. AP effects were assessed by event-related potentials (ERPs), reaction times (RTs) and subjective ratings. The ratings were also assessed (Study 2) in undergraduate restrained (RES) and unrestrained eaters (UNRES). RESULTS: Study 1 demonstrated stronger AP effects in both ED groups compared to HC on RTs and subjective ratings. ERPs showed AP effects only in the BN group. Restrained eaters showed similar, albeit less pronounced, priming effects on subjective ratings. CONCLUSIONS: ED patients associate shape/weight concerns with the non-appearance-related SE domains of interpersonal relationships and achievement/performance. These associations seem to be encoded deeper in BN patients relative to the other groups. Links between shape/weight and SE explain how body dissatisfaction impacts on self-esteem and mood in ED. The existence of similar associations in restrained eaters supports a continuum model according to which increasing associations between shape/weight and SE go along with increasing levels of ED symptoms.

Manual and verbal responses to completely masked (unreportable) stimuli: exploring some conditions for the metacontrast dissociation.

As reported by Neumann and Klotz [1994, in Attention and Performance XV: Conscious and Nonconscious Information Processing Eds C Umiltà, M Moscovitch (Cambridge, MA: MIT Press) pp 123-150], a geometric shape masked by metacontrast can affect response latency (RT) even if it is not visible, i.e. if it yields a d' value of zero in a signal-detection (SD) task (metacontrast dissociation). In the initial study as well as in most subsequent experiments, the RT task was manual and the SD task was verbal. Hence tasks and output modes were confounded. In the present study, two experiments were conducted to find out which of these factors is responsible for the metacontrast dissociation. In experiment 1, participants performed an RT task in either a manual or a verbal output mode. In experiment 2, these output modes were compared in an SD task. Independently of output modes, the masked primes affected RT but could not be detected in the SD task. It is concluded that tasks, but not output modes, are crucial for the metacontrast dissociation. Implications for the mechanisms underlying the metacontrast dissociation and for the functional difference between judgments and responses are discussed.