[Decision-making and delusion. A study on decision-making in delusional, depressive and healthy subjects]

Delusion as a phenomenon was always in the focus of psychiatric interest. Explanations for its origin reach from disturbed perception or affect to deficits in cognition. In our study we investigated 20 deluded, 20 depressive and 20 healthy subjects in order to find out differences in decision making, while a neutral test situation. Our hypothesis was that deluded subjects need less information for decision making and tend less to change their decision, made before, than both control groups will do this. For examination our hypothesis a modified version of "Probabilistic Inference Task" by Philips and Edwards was performed. In summary we found that deluded subjects need less information for decisions making than the control groups. Furthermore, decision making of deluded subjects seems more impulsive and less referring to formal logical criteria than it was found in depressed and healthy volunteers.