ABSTRACT
OBJECTIVE: To explore decision-making, impulsiveness and temperamental traits in patients suffering from eating disorders (EDs), as compared with healthy controls (HC). METHOD: Fifty-one patients affected by ED (fourteen with anorexia restricting subtype, AN-R; fourteen with bulimia, BN; thirteen with anorexia bingeing/purging subtype, AN-BP; ten with binge-eating disorder, BED) and twenty-eight HC. The patients, recruited at the Section of Psychiatry of the University of Pisa (Italy, were evaluated with a battery of neuropsychological questionnaires, including the IOWA Gambling Task (IGT), the Barratt Impulsiveness Scale (BIS-11), the Temperament and Character Inventory (TCI), the Frontal Assessment Battery (FAB) and the Hamilton Depression Rating Scale (HAM-D). RESULTS: The results indicated that AN-R, AN-BP and BN patients showed poorer IGT performances than HC (p < .05), while BED performances were similar to those of HC. IGT scores suggested the existence of similarities in decision-making performances of AN-BP and BN patients, as they performed differently from HC starting from block 3 (F(16.2)=1.7). In addition, differences between AN-BP/BN and AN-R patients were detected, given that they performed differently starting from block 4. As far as BIS-11 is concerned, AN-BP and BN patients reached the highest BIS total scores, when compared with the other groups. Further, they shared similar temperamental and impulsiveness profiles, as demonstrated by their BIS-11 'motor impulsiveness' scores, and by their TCI 'novelty seeking', 'reward dependence' and 'persistence' dimensions. The post-hoc analyses revealed that both AN groups (namely, AN-R and AN-BP) scored significantly lower than HC on the FAB. No patients fulfilled the criteria for the diagnosis of a current major depression. CONCLUSIONS: Decision-making deficits are common in EDs. In AN-R these seem related to cognitive styles, while in AN-BP and BN patients with temperament features and impulsiveness traits.
ABSTRACT
Recent researches reported behavioral and emotional impairment in Parkinson's disease (PD), even in the earliest stages. This impairment affects also decision-making and learning processes. The Iowa gambling task (IGT) is commonly used to examine the decision-making capacity. The purpose of the present study was to investigate the neural correlates of feedback evaluation in the decision-making process into a learning context, using IGT and event-related potentials (ERPs) in a group of non-demented medicated PD patients. Fifteen PD patients and 15 healthy controls were recruited for the study. PD patients were administrated a basic neuropsychological assessment oriented to exclude cognitive impairments. Both groups underwent the computerized IGT during electroencephalography (EEG) registration. To analyse ERPs, continuous EEG data were epoched within a time-window starting 1000 ms before and ending 1000 ms after feedback presentation and averaged separately for positive (i.e., win condition) and negative (i.e., loss condition) feedbacks. Behavioral data revealed a significant lower performance of PD patients (p < 0.05) compared with the controls. While controls demonstrated a correct feedback evaluation, PD patients did not show any learning, selecting more disadvantageous decks even in the last part of task. Furthermore, ERPs results revealed that controls showed a significant difference (p < 0.05) in ERPs morphology recorded after the win and the loss conditions, suggesting that positive and negative feedbacks were differently evaluated and processed. PD patients showed a different pattern: their ERPs morphology was the same for positive and negative feedback. Interestingly, our ERPs results suggest that in PD patients an incorrect evaluation of context-relevant outcomes could be the reason of a poor performance in decision-making tasks, and could explain cognitive and behavioral problems related to impulse control disorder.
