Department of Psychiatry, Academic Medical Centre, Amsterdam, The Netherlands.
Psychol Med. 2010 Aug;40(8):1325-36. doi: 10.1017/S0033291709991814. Epub 2009 Nov 17.
Cannabis use is common in patients with recent-onset schizophrenia and this is associated with poor disease outcome. More insight in the cognitive-motivational processes related to cannabis use in schizophrenia may inform treatment strategies. The present study is the first known to compare implicit and explicit cannabis associations in individuals with and without psychotic disorder.
Participants consisted of 70 patients with recent-onset psychotic disorder and 61 healthy controls with various levels of cannabis use. Three Single-Category Implicit Association Tests (SC-IAT) were used to assess 'relaxed', 'active' and 'negative' implicit associations towards cannabis use. Explicit expectancies of cannabis use were assessed with a questionnaire using the same words as the SC-IAT.
There were no differences in implicit associations between patients and controls; however, patients scored significantly higher on explicit negative affect expectancies than controls. Both groups demonstrated strong negative implicit associations towards cannabis use. Explicit relaxed expectancies were the strongest predictors of cannabis use and craving. There was a trend for implicit active associations to predict craving.
The findings indicate that patients suffering from schizophrenia have associations towards cannabis similar to controls, but they have stronger negative explicit cannabis associations. The strong negative implicit associations towards cannabis could imply that users of cannabis engage in a behaviour they do not implicitly like. Explicit relaxing expectancies of cannabis might be an important mediator in the continuation of cannabis use in patients and controls.
近期发病的精神分裂症患者中常见大麻使用情况，这与疾病预后不良有关。更多地了解与精神分裂症中大麻使用相关的认知-动机过程，可能有助于制定治疗策略。本研究首次比较了有和无精神病障碍个体对大麻的内隐和外显关联。
参与者包括 70 名近期发病的精神病患者和 61 名具有不同大麻使用水平的健康对照者。使用三种单类别内隐联想测试（SC-IAT）评估对大麻使用的“放松”、“积极”和“消极”内隐关联。使用与 SC-IAT 相同的词的问卷评估大麻使用的外显期望。
患者与对照组之间的内隐关联无差异；然而，患者的外显负性情感期望得分显著高于对照组。两组均表现出对大麻使用的强烈负性内隐关联。外显放松期望是大麻使用和渴望的最强预测因素。内隐积极关联预测渴望的趋势明显。
研究结果表明，患有精神分裂症的患者对大麻的关联与对照组相似，但他们对大麻的外显负性关联更强。对大麻的强烈负性内隐关联可能表明使用者从事的是他们在内隐上不喜欢的行为。对大麻的外显放松期望可能是患者和对照组中继续使用大麻的一个重要中介因素。
