Schizophrenia Division and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, Ontario M5T 1R8, Canada; Institute of Medical Science, Faculty of Medicine, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.
Schizophrenia Division and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, Ontario M5T 1R8, Canada.
Schizophr Res. 2019 Apr;206:400-406. doi: 10.1016/j.schres.2018.10.012. Epub 2018 Nov 22.
Planning and executing goal-directed behaviours are critical final steps in translating motivation into action. Amotivation is a key feature of schizophrenia, but its impact on goal-directed functioning has not been extensively studied in an objective and ecologically valid manner. To address this, we investigated goal-directed planning and action in schizophrenia using a virtual reality task, the Multitasking in the City Test (MCT). The MCT was administered to 49 outpatients with schizophrenia and 55 healthy controls, and required participants to complete a series of errands in a virtual city. Ability to complete the task as directed was assessed by a performance score based on errands completed and errors committed. Task efficiency was evaluated by the total distance travelled, and an index of path efficiency comparing an optimal route with the traversed route. Schizophrenia participants had lower performance scores, travelled farther, and had reduced path efficiency compared to healthy controls. Greater distance travelled and lower path efficiency in schizophrenia were related to amotivation. Path efficiency in schizophrenia was also related to neurocognition, including planning ability; notably, this relationship appeared to be independent of the relationship with amotivation. Individuals with schizophrenia demonstrated impaired goal-directed planning and action in the context of a simulated everyday errands task, both in terms of reduced capacity to complete errands and reduced efficiency in doing so. The latter may manifest as diminished real-world motivated and functional behaviour in patients with schizophrenia and indicates a specific deficit in the execution of planned behaviour.
规划和执行目标导向行为是将动机转化为行动的关键最后步骤。动机缺乏是精神分裂症的一个主要特征，但它对目标导向功能的影响尚未以客观和生态有效的方式进行广泛研究。为了解决这个问题，我们使用虚拟现实任务——城市多任务测试（MCT）来研究精神分裂症中的目标导向规划和行为。MCT 被施用于 49 名精神分裂症门诊患者和 55 名健康对照者，要求参与者在虚拟城市中完成一系列差事。根据完成的差事和犯的错误，基于绩效得分来评估按指示完成任务的能力。通过总距离评估任务效率，并通过与最佳路线比较的路径效率指数来评估路径效率。与健康对照组相比，精神分裂症患者的绩效得分较低，行进的距离更远，路径效率降低。精神分裂症患者的行进距离越大，路径效率越低，与动机缺乏有关。精神分裂症患者的路径效率也与神经认知有关，包括规划能力；值得注意的是，这种关系似乎独立于与动机缺乏的关系。在模拟日常差事任务的背景下，精神分裂症个体表现出目标导向规划和行为受损，无论是在完成差事的能力降低还是在完成差事的效率降低方面。后者可能表现为精神分裂症患者现实世界中动机和功能行为的减弱，并表明计划行为的执行存在特定缺陷。
