Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, New York.
Division of Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, New York.
Depress Anxiety. 2019 May;36(5):433-441. doi: 10.1002/da.22888. Epub 2019 Mar 21.
Identifying brain activity patterns that are associated with suicidal ideation (SI) may help to elucidate its pathogenesis and etiology. Suicide poses a significant public health problem, and SI is a risk factor for suicidal behavior.
Forty-one unmedicated adult participants in a major depressive episode (MDE), 26 with SI on the Beck Scale for Suicidal Ideation and 15 without SI, underwent resting-state functional magnetic resonance imaging scanning. Twenty-one healthy volunteers (HVs) were scanned for secondary analyses. Whole brain analysis of both amplitude of low-frequency fluctuations (ALFFs) and fractional ALFF was performed in MDE subjects to identify regions where activity was associated with SI.
Subjects with SI had greater ALFF than those without SI in two clusters: one in the right hippocampus and one in the thalamus and caudate, bilaterally. Multi-voxel pattern analysis distinguished between those with and without SI. Post hoc analysis of the mean ALFF in the hippocampus cluster found it to be associated with a delayed recall on the Buschke memory task. Mean ALFF from the significant clusters was not associated with depression severity and did not differ between MDE and HV groups.
These results indicate that SI is associated with altered resting-state brain activity. The pattern of elevated activity in the hippocampus may be related to how memories are processed.
识别与自杀意念（SI）相关的大脑活动模式可能有助于阐明其发病机制和病因。自杀是一个严重的公共卫生问题，SI 是自杀行为的一个风险因素。
41 名未接受药物治疗的重度抑郁症发作（MDE）患者，26 名贝克自杀意念量表（Beck Scale for Suicidal Ideation）上有 SI，15 名无 SI，进行了静息态功能磁共振成像扫描。21 名健康志愿者（HV）进行了二次分析。对 MDE 患者进行全脑分析，包括低频振幅（ALFF）和分数 ALFF，以确定与 SI 相关的活动区域。
有 SI 的受试者在两个簇中的 ALFF 高于无 SI 的受试者：一个在右侧海马体，一个在丘脑和尾状核，双侧。多体素模式分析可区分有 SI 和无 SI 的受试者。对海马体簇中平均 ALFF 的事后分析发现，它与 Buschke 记忆任务的延迟回忆有关。来自显著簇的平均 ALFF 与抑郁严重程度无关，并且在 MDE 和 HV 组之间没有差异。
这些结果表明，SI 与静息状态下大脑活动的改变有关。海马体中活性升高的模式可能与记忆处理方式有关。
