Decision making under uncertainty and mood induction: further evidence for liberal acceptance in schizophrenia.
BACKGROUND
Cognitive biases, especially jumping to conclusions (JTC), are ascribed a vital role in the pathogenesis of schizophrenia. This study set out to explore motivational factors for JTC using a newly developed paradigm.


METHODS
Twenty-seven schizophrenia patients and 32 healthy controls were shown 15 classical paintings, divided into three blocks. Four alternative titles (one correct and three lure titles) had to be appraised according to plausibility (0-10). Optionally, participants could decide for one option and reject one or more alternatives. In random order across blocks, anxiety-evoking music, happy music or no music was played in the background.


RESULTS
Patients with schizophrenia, particularly those with delusions, made more decisions than healthy subjects. In line with the liberal acceptance (LA) account of schizophrenia, the decision threshold was significantly lowered in patients relative to controls. Patients were also more prone than healthy controls to making a decision when the distance between the first and second best alternative was close. Furthermore, implausible alternatives were judged as significantly more plausible by patients. Anxiety-evoking music resulted in more decisions in currently deluded patients relative to non-deluded patients and healthy controls.


CONCLUSIONS
The results confirm predictions derived from the LA account and assert that schizophrenia patients decide hastily under conditions of continued uncertainty. The fact that mood induction did not exert an overall effect could be due to the explicit nature of the manipulation, which might have evoked strategies to counteract their influence.
University Medical Center Hamburg-Eppendorf, Hospital for Psychiatry and Psychotherapy, Hamburg, Germany. moritz@uke.uni-hamburg.de
S
S
Moritz
R
R
Veckenstedt
S
S
Randjbar
B
B
Hottenrott
T S
TS
Woodward
F V
FV
von Eckstaedt
C
C
Schmidt
L
L
Jelinek
T M
TM
Lincoln
D000328:Adult; D000339:Affect; D001007:Anxiety / Q000523:psychology; D003072:Cognition Disorders / Q000175:diagnosis* / Q000523:psychology*; D003657:Decision Making; D003702:Delusions / Q000175:diagnosis / Q000523:psychology; D005260:Female; D006240:Happiness; D006801:Humans; D007175:Impulsive Behavior / Q000175:diagnosis* / Q000523:psychology; D008297:Male; D011939:Mental Recall; D008875:Middle Aged; D009146:Music; D010364:Pattern Recognition, Visual; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000175:diagnosis*; D012565:Schizophrenic Psychology; D035501:Uncertainty; D055815:Young Adult