Functional Brain Imaging Unit, Wohl Institute for Advanced Imaging, Tel-Aviv Sourasky Medical Center, 6, Weizmann Street, 64239 Tel-Aviv, Israel.
Functional Brain Imaging Unit, Wohl Institute for Advanced Imaging, Tel-Aviv Sourasky Medical Center, 6, Weizmann Street, 64239 Tel-Aviv, Israel; Psychology Department, Tel-Aviv University, Tel-Aviv, Israel; Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
Eur Psychiatry. 2014 Mar;29(3):160-6. doi: 10.1016/j.eurpsy.2013.02.004. Epub 2013 Jun 10.
A substantial proportion of schizophrenia patients also meets DSM-IV criteria for obsessive-compulsive disorder (OCD). Schizophrenia with OCD ("schizo-obsessive") patients are characterized by distinct clinical characteristics, treatment response and prognosis. Whether schizo-obsessive patients exhibit a distinct pattern of brain activation is yet unknown. To address this question, the present functional magnetic resonance imaging (fMRI) study explicitly compared alterations in brain activation and functional connectivity (FC) underlying a working memory deficit in schizophrenia patients with and without OCD.
fMRI was applied during the N-back working memory (WM) task in three groups: schizo-obsessive (n=16), schizophrenia (n=17) and matched healthy volunteers (n=20). WM-related activation in the right dorsolateral prefrontal cortex (DLPFC) and the right caudate nucleus, brain areas relevant to schizophrenia and OCD, and FC analysis were used for the evaluation.
The two schizophrenia groups with and without OCD exhibited a similar reduction in activation in the right DLPFC and right caudate, as well as decreased FC compared to the healthy controls. Notably, reduced regional brain activation was not related to severity of schizophrenic or OCD symptoms.
Schizo-obsessive patients do not differ from their non-OCD schizophrenia counterparts in brain activation patterns during the N-back WM task. Cognitive paradigms taping alternative neural networks (e.g., orbitofrontal cortex) particularly relevant to OCD, are warranted in the search for potential distinctive brain activation patterns of the schizo-obsessive subgroup.
相当一部分精神分裂症患者也符合 DSM-IV 强迫症（OCD）的标准。伴有强迫症的精神分裂症（“精神分裂-强迫”）患者具有明显的临床特征、治疗反应和预后。精神分裂-强迫患者是否表现出独特的大脑激活模式尚不清楚。为了解决这个问题，本项功能磁共振成像（fMRI）研究明确比较了伴有和不伴有强迫症的精神分裂症患者在工作记忆缺陷的大脑激活和功能连接（FC）方面的改变。
在三组中应用 fMRI 进行 N-back 工作记忆（WM）任务：精神分裂-强迫组（n=16）、精神分裂症组（n=17）和匹配的健康志愿者组（n=20）。评估使用了与精神分裂症和强迫症相关的右侧背外侧前额叶皮层（DLPFC）和右侧尾状核的 WM 相关激活以及 FC 分析。
伴有和不伴有强迫症的两组精神分裂症患者在右侧 DLPFC 和右侧尾状核的激活均出现相似的减少，与健康对照组相比，FC 也降低。值得注意的是，区域脑激活的减少与精神分裂症或 OCD 症状的严重程度无关。
在 N-back WM 任务中，精神分裂-强迫患者的大脑激活模式与非 OCD 精神分裂症患者没有差异。需要使用涉及到与 OCD 特别相关的替代神经网络（例如眶额皮层）的认知范式，以寻找精神分裂-强迫亚组潜在的独特大脑激活模式。
