Iowa gambling task in schizophrenia: a review and new data in patients with schizophrenia and co-occurring cannabis use disorders.
BACKGROUND
We reviewed previous studies comparing schizophrenia patients and healthy subjects for performance on the Iowa Gambling Task (IGT) (a laboratory task designed to measure emotion-based decision-making), and found mixed results. We hypothesize that deficits in IGT performance in schizophrenia may be more specifically related to concurrent substance use disorders. To test this hypothesis, we compared schizophrenia patients with (SCZ((+))) or without (SCZ((-))) cannabis use disorders, to healthy subjects, on measures of cognition and IGT performance.


METHODS
A comprehensive battery of cognitive tests and the IGT were administered to three groups of subjects: (1) 13 subjects with DSM-IV diagnosis of schizophrenia and no concurrent substance use disorders (mean age: 28+/-12 (SD); 54% males); (2) 14 subjects with schizophrenia and concurrent cannabis use disorders (mean age: 29+/-9 (SD); 71% males); and (3) 20 healthy subjects (mean age 33+/-10 (SD); 60% males).


RESULTS
Compared to the healthy group, both schizophrenia groups were cognitively more impaired, and did worse on IGT performance. There were no differences between SCZ((+)) and SCZ((-)) patients on most of the cognitive tests, and IGT performance.


CONCLUSIONS
Schizophrenia patients show widespread impairments in several cognitive domains and emotion-based decision-making. These results are consistent with the evidence that schizophrenia reflects a dorsolateral and orbitofrontal/ventromedial prefrontal cortex dysfunction. More intriguing, it appears that the concurrent abuse of cannabis has no compounding effects on cognition, as well as emotion/affect-based decision-making.
Sevy
Serge
S
Department of Psychiatry Research, Zucker Hillside Hospital, North-Shore-Long Island Jewish Health System, 75-59 263rd Street, Glen Oaks, NY, 11004, USA. sevy@lij.edu
Burdick
Katherine E
KE
Visweswaraiah
Hema
H
Abdelmessih
Sherif
S
Lukin
Meredith
M
Yechiam
Eldad
E
Bechara
Antoine
A
D000293:Adolescent; D000328:Adult; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology; D015897:Comorbidity; D003657:Decision Making; D039721:Diagnostic and Statistical Manual of Mental Disorders; D007174:Disruptive, Impulse Control, and Conduct Disorders / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D005715:Gambling / Q000523:psychology*; D006801:Humans; D008297:Male; D002189:Marijuana Abuse / Q000175:diagnosis / Q000453:epidemiology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D011581:Psychological Tests; D012559:Schizophrenia / Q000175:diagnosis / Q000453:epidemiology*; D012720:Severity of Illness Index