Fajnerová Iveta, Rodriguez Mabel, Levčík David, Konrádová Lucie, Mikoláš Pavol, Brom Cyril, Stuchlík Aleš, Vlček Kamil, Horáček Jiří
Prague Psychiatric Center Prague, Czech Republic ; Department of Neurophysiology of Memory, Institute of Physiology, Academy of Sciences of the Czech Republic v.v.i. Prague, Czech Republic ; Department of Psychiatry and Medical Psychology, 3rd Faculty of Medicine, Charles University in Prague Prague, Czech Republic.
Prague Psychiatric Center Prague, Czech Republic.
Front Behav Neurosci. 2014 May 27;8:157. doi: 10.3389/fnbeh.2014.00157. eCollection 2014.
Cognitive deficit is considered to be a characteristic feature of schizophrenia disorder. A similar cognitive dysfunction was demonstrated in animal models of schizophrenia. However, the poor comparability of methods used to assess cognition in animals and humans could be responsible for low predictive validity of current animal models. In order to assess spatial abilities in schizophrenia and compare our results with the data obtained in animal models, we designed a virtual analog of the Morris water maze (MWM), the virtual Four Goals Navigation (vFGN) task.
Twenty-nine patients after the first psychotic episode with schizophrenia symptoms and a matched group of healthy volunteers performed the vFGN task. They were required to find and remember four hidden goal positions in an enclosed virtual arena. The task consisted of two parts. The Reference memory (RM) session with a stable goal position was designed to test spatial learning. The Delayed-matching-to-place (DMP) session presented a modified working memory protocol designed to test the ability to remember a sequence of three hidden goal positions.
Data obtained in the RM session show impaired spatial learning in schizophrenia patients compared to the healthy controls in pointing and navigation accuracy. The DMP session showed impaired spatial memory in schizophrenia during the recall of spatial sequence and a similar deficit in spatial bias in the probe trials. The pointing accuracy and the quadrant preference showed higher sensitivity toward the cognitive deficit than the navigation accuracy. Direct navigation to the goal was affected by sex and age of the tested subjects. The age affected spatial performance only in healthy controls.
Despite some limitations of the study, our results correspond well with the previous studies in animal models of schizophrenia and support the decline of spatial cognition in schizophrenia, indicating the usefulness of the vFGN task in comparative research.
认知缺陷被认为是精神分裂症的一个特征性表现。在精神分裂症动物模型中也证实了类似的认知功能障碍。然而，用于评估动物和人类认知的方法可比性较差，这可能是当前动物模型预测效度较低的原因。为了评估精神分裂症患者的空间能力，并将我们的结果与在动物模型中获得的数据进行比较，我们设计了莫里斯水迷宫（MWM）的虚拟模拟任务，即虚拟四目标导航（vFGN）任务。
29名首次出现精神分裂症症状的精神病发作后患者和一组匹配的健康志愿者进行了vFGN任务。他们需要在一个封闭的虚拟场景中找到并记住四个隐藏的目标位置。该任务由两部分组成。具有稳定目标位置的参考记忆（RM）环节旨在测试空间学习能力。延迟位置匹配（DMP）环节采用了一种改进的工作记忆方案，旨在测试记住三个隐藏目标位置序列的能力。
在RM环节中获得的数据显示，与健康对照组相比，精神分裂症患者在指向和导航准确性方面的空间学习能力受损。DMP环节显示，精神分裂症患者在回忆空间序列时空间记忆受损，在探测试验中的空间偏差也有类似缺陷。指向准确性和象限偏好对认知缺陷的敏感性高于导航准确性。直接导航到目标受测试对象的性别和年龄影响。年龄仅在健康对照组中影响空间表现。
尽管本研究存在一些局限性，但我们的结果与先前在精神分裂症动物模型中的研究结果非常吻合，支持精神分裂症患者空间认知能力下降的观点，表明vFGN任务在比较研究中的有用性。
