ABSTRACT

Cannabis use can increase severity of symptoms and risk of relapse for people with psychosis. Childhood sexual abuse and high schizotypy increase the risk further. The mechanisms involved remain unclear, and this limits psychological therapies. In three linked studies, we examined the role of two candidate mechanisms – external attribution and cognitive fusion. Study 1 examined these processes in a general population sample and showed that paranoia, psychotic-type experiences, and linked distress were higher in cannabis-users, and mediated by cognitive fusion but not external attribution. Study 2 examined the impact of established risk factors in general population cannabis-users and showed that external attribution and cognitive fusion partially or fully accounted for the effects of childhood sexual abuse and schizotypy on paranoia, psychotic-type experiences and linked distress. Study 3 examined these same processes in a clinical population of people with psychosis and found that external attribution and cognitive fusion partially or fully accounted for the impact of gender, age of first use, sexual abuse and schizotypy. External attribution and cognitive fusion may be key mechanisms in the maintenance of cannabis-related paranoia and account for the impact of established risk factors. We present a cognitive model incorporating these processes to inform clinical practice.

摘要

大麻的使用会增加精神病患者的症状严重程度和复发风险。童年时期的性虐待和精神分裂症进一步增加了患病风险。所涉及的机制尚不清楚，这限制了心理疗法。在三项相关研究中，我们研究了两种候选机制的作用-外部归因和认知融合。研究1在一般人群样本中检查了这些过程，结果表明，大麻使用者的偏执狂，精神病类型经历和相关困扰感较高，并且是由认知融合而非外部归因所介导的。研究2检验了既定危险因素对普通人群大麻使用者的影响，并表明外部归因和认知融合部分或完全解释了儿童期性虐待和精神分裂症对妄想症的影响，精神病类型的经历和相关的困扰。研究3在临床的精神病患者中检查了相同的过程，发现外部归因和认知融合部分或完全解释了性别，首次使用年龄，性虐待和精神分裂症的影响。外部归因和认知融合可能是维持与大麻有关的妄想症的关键机制，并说明了已建立的危险因素的影响。我们提出了一种认知模型，将这些过程纳入临床实践。外部归因和认知融合可能是维持与大麻有关的妄想症的关键机制，并说明了已建立的危险因素的影响。我们提出了一种认知模型，将这些过程纳入临床实践。外部归因和认知融合可能是维持与大麻有关的妄想症的关键机制，并说明了已建立的危险因素的影响。我们提出了一种认知模型，将这些过程纳入临床实践。