Alders Gésine L, Milne Andrea M B, Minuzzi Luciano, Frey Benicio N, MacQueen Glenda M, Hall Geoffrey B
Department of Psychiatry and Behavioural Neurosciences, Faculty of Health Sciences.
Mood Disorders Research Unit, St. Joseph's Centre for Integrated Healthcare, Hamilton, Ontario.
Neuroreport. 2019 Jan 2;30(1):46-52. doi: 10.1097/WNR.0000000000001163.
The hippocampus is implicated in the pathophysiology of major depressive disorder (MDD), with evidence that morphological changes occur with disease progression. It was hypothesized that treatment-naive patients with depression would show performance deficits in hippocampus-dependent memory trials, with concurrent hippocampal activation deficits on functional magnetic resonance imaging, compared with control participants. Thirteen treatment-naive patients with MDD and 13 control participants completed a hippocampus-dependent memory functional magnetic resonance imaging process-dissociation task. On behavioural measures of habit memory and guessing, there were no significant differences between groups. Functional magnetic resonance imaging analysis indicated that compared with the control group, the MDD group showed increased activation in the parahippocampal gyrus and hippocampus on habit memory and nonitem trials. These alterations in hippocampal functioning with preserved cognitive performance on a test of hippocampus-dependent memory in MDD may be indicative of a compensatory mechanism.
海马体与重度抑郁症（MDD）的病理生理学有关，有证据表明其形态变化会随着疾病进展而出现。研究假设，与对照组参与者相比，未经治疗的抑郁症患者在依赖海马体的记忆试验中会表现出功能缺陷，同时在功能磁共振成像上会出现海马体激活缺陷。13名未经治疗的MDD患者和13名对照参与者完成了一项依赖海马体的记忆功能磁共振成像过程分离任务。在习惯记忆和猜测的行为测量方面，两组之间没有显著差异。功能磁共振成像分析表明，与对照组相比，MDD组在习惯记忆和非项目试验中，海马旁回和海马体的激活增加。在MDD患者依赖海马体的记忆测试中，海马体功能的这些改变伴随着认知表现的保留，这可能表明存在一种代偿机制。
