Impact of schizophrenia on anterior and posterior hippocampus during memory for complex scenes.
Impact of schizophrenia on anterior and posterior hippocampus during memory for complex scenes.
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DOI：
10.1016/j.nicl.2016.11.017
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发表时间：
2017
影响因子：
4.2
通讯作者：
Ranganath, C.
中科院分区：
文献类型：
--
作者：
Ragland, J. D.;Layher, E.;Hannula, D. E.;Niendam, T. A.;Lesh, T. A.;Solomon, M.;Carter, C. S.;Ranganath, C.
海马功能障碍被认为是精神分裂症记忆缺陷的一种机制。现有的证据表明，前海马和后海马可能受到不同的影响。因此，我们使用功能性磁共振成像来检验这一假设，即精神分裂症患者的后海马活动不成比例地减少，特别是在空间记忆提取过程中。26名健康参与者和24名来自加州大学戴维斯分校早期精神病项目的精神分裂症患者进行了研究，同时在3特斯拉西门子扫描仪上获得了fMRI。在编码过程中，参与者通过关于项目特征的问题（例如，“这盏灯有方形的灯罩吗？”）或空间位置（例如，“台灯在沙发旁边的桌子上吗？”）。在测试中，参与者确定场景是否改变或不变。功能磁共振成像分析对比激活的先验区域的兴趣（ROI）在前和后海马正确识别项目的变化和空间的变化。正如预测的那样，精神分裂症患者在检测空间变化时后海马的激活减少，但在检测项目变化时则没有。出乎意料的是，患者在检测项目变化时表现出前海马的激活增加。全脑分析显示，减少额顶叶和纹状体的激活患者的空间，但不是项目变化试验。结果表明，海马功能障碍的梯度，其中后海马-这是必要的处理细粒度的空间关系-是不活跃的，和前海马-这可能会处理上下文更全面-是过度活跃。精神分裂症患者对场景中物体之间的空间关系表现出记忆受损。患者在空间记忆时后海马激活较少，而在项目记忆时前海马激活较多。精神分裂症患者海马功能障碍的这种梯度表明，在未来的研究中，不应将其作为一个单一的结构进行研究。
Hippocampal dysfunction has been proposed as a mechanism for memory deficits in schizophrenia. Available evidence suggests that the anterior and posterior hippocampus could be differentially affected. Accordingly, we used fMRI to test the hypothesis that activity in posterior hippocampus is disproportionately reduced in schizophrenia, particularly during spatial memory retrieval. 26 healthy participants and 24 patients with schizophrenia from the UC Davis Early Psychosis Program were studied while fMRI was acquired on a 3 Tesla Siemens scanner. During encoding, participants were oriented to critical items through questions about item features (e.g., “Does the lamp have a square shade?”) or spatial location (e.g., “Is the lamp on the table next to the couch?”). At test, participants determined whether scenes were changed or unchanged. fMRI analyses contrasted activation in a priori regions of interest (ROI) in anterior and posterior hippocampus during correct recognition of item changes and spatial changes. As predicted, patients with schizophrenia exhibited reduced activation in the posterior hippocampus during detection of spatial changes but not during detection of item changes. Unexpectedly, patients exhibited increased activation of anterior hippocampus during detection of item changes. Whole brain analyses revealed reduced fronto-parietal and striatal activation in patients for spatial but not for item change trials. Results suggest a gradient of hippocampal dysfunction in which posterior hippocampus – which is necessary for processing fine-grained spatial relationships – is underactive, and anterior hippocampus – which may process context more globally - is overactive. Patients with schizophrenia show impaired memory for spatial relationships amongst objects in scenes. Patients have less posterior hippocampal activation during spatial memory and more anterior hippocampal activation during item memory. This gradient of hippocampal dysfunction in schizophrenia, suggests that it should not be examined as a unitary structure in future studies.
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影响因子：
2.9
作者：
Hannula DE;Althoff RR;Warren DE;Riggs L;Cohen NJ;Ryan JD
通讯作者：
Ryan JD
影响因子：
6.6
作者：
Kraguljac, Nina Vanessa;White, David Matthew;Lahti, Adrienne Carol
通讯作者：
Lahti, Adrienne Carol
影响因子：
4.5
作者：
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通讯作者：
Konradi, Christine
影响因子：
16.2
作者：
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14.5
作者：
Benetti, Stefania;Mechelli, Andrea;McGuire, Philip
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