The positive link between executive function and lifetime cannabis use in schizophrenia is not explained by current levels of superior social cognition.
There has been a growing link between a history of cannabis use and neurocognitive performance in patients with schizophrenia. Fewer neurocognitive deficits may be a marker of the superior social cognition needed to obtain illicit substances, or cannabis use may indicate a distinct path to schizophrenia with less neurocognitive vulnerability. This study sought to determine whether the relationship of cannabis use and executive function exists independently of social cognition. Eighty-seven patients with schizophrenia were administered measures of social cognition and executive function. Social cognition was assessed using the Bell-Lysaker Emotion Recognition Test to measure affect recognition, and the Eyes and Hinting Tests to measure theory of mind. Executive function was assessed by the Mental Flexibility component of the Delis-Kaplan Executive Functioning Scale. The relations between the variables were examined with structural equation modeling. Cannabis use positively related to executive function, negatively related to affect recognition, and had no relationship with theory of mind. There were no indirect effects of other illicit substances on amount of regular cannabis use. Alcohol use was related to worse affect recognition. The relationship between cannabis use and better executive function was supported and was not explained by superior social cognition.
Division of Psychiatry, Haukeland University Hospital, Bergen, Norway; Department of Biological and Medical Psychology, University of Bergen, Norway.
Siri
S
Helle
Division of Psychiatry, Haukeland University Hospital, Bergen, Norway; Department of Addiction Medicine, Haukeland University Hospital, Bergen, Norway; Department of Clinical Psychology, University of Bergen, Norway.
Else-Marie
EM
Løberg
Division of Psychiatry, Haukeland University Hospital, Bergen, Norway.
Rolf
R
Gjestad
Roudebush Veteran Affairs Medical Center, Indianapolis, IN, USA; Indiana University - Bloomington, Bloomington, IN, USA.
Ashley M
AM
Schnakenberg Martin
Roudebush Veteran Affairs Medical Center, Indianapolis, IN, USA; Indiana University School of Medicine, Indianapolis, IN, USA. Electronic address: plysaker@iupui.edu.
Paul H
PH
Lysaker
D000328:Adult; D003071:Cognition / Q000502:physiology; D003430:Cross-Sectional Studies; D004644:Emotions; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008385:Marijuana Smoking / Q000523:psychology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D012565:Schizophrenic Psychology; D012919:Social Behavior; D012938:Social Perception; D056345:Theory of Mind / Q000502:physiology
Cannabis; Cognition; Emotional intelligence; Executive function; Schizophrenia; Theory of mind