Granger Steven J, Olson Elizabeth A, Weinstein Sylvie J, Vratimos Isabelle R, Lynch Brian, Ren Boyu, Rosso Isabelle M
Center for Depression, Anxiety, and Stress Research, McLean Hospital, Belmont, MA, USA.
Department of Psychiatry, Harvard Medical School, Boston, MA, USA.
Cogn Affect Behav Neurosci. 2025 Jan 9. doi: 10.3758/s13415-024-01252-2.
Post-traumatic stress and major depressive disorders are associated with "overgeneral" autobiographical memory, or impaired recall of specific life events. Interpersonal trauma exposure, a risk factor for both conditions, may influence how symptomatic trauma-exposed (TE) individuals segment everyday events. The ability to parse experience into units (event segmentation) supports memory. Neural state transitions occur within a cortical hierarchy and play a key role in event segmentation, with regions like the occipital cortex, angular gyrus, and striatum involved in parsing event structure. We examined whether interpersonal trauma exposure was associated with alterations in the cortical hierarchy and striatal activity at neural state transitions in symptomatic TE versus healthy control (HC) individuals. Fifty older adolescents and young adults (29 TE, 21 HC) viewed the film "Partly Cloudy" during functional magnetic resonance imaging. A greedy-state boundary search algorithm assessed the optimal number of events, quality, and segmentation agreement of neural state transitions in the occipital cortex and angular gyrus. Striatal (nucleus accumbens, caudate, and putamen) activity was assessed at occipital and angular gyrus-evoked state transitions. Compared to HCs, TE participants displayed less occipital and greater angular gyrus-evoked optimal number of neural state transitions. TE participants also displayed lower quality of neural state segmentation solutions in occipital and angular cortices compared to HCs. Additionally, TE participants had less putamen activity at angular gyrus-evoked state transitions than HCs. This investigation provides neurobiological insights into aberrant event segmentation in symptomatic TE individuals, shedding light on mechanisms influencing overgeneral memory in trauma-related disorders.
创伤后应激障碍和重度抑郁症与“过度概括”的自传体记忆有关，即对特定生活事件的回忆受损。人际创伤暴露是这两种疾病的一个风险因素，可能会影响有创伤暴露症状（TE）的个体对日常事件的划分方式。将经历解析为单元的能力（事件划分）有助于记忆。神经状态转换发生在皮层层级结构中，并在事件划分中起关键作用，枕叶皮层、角回和纹状体等区域参与解析事件结构。我们研究了人际创伤暴露是否与有症状的TE个体相对于健康对照（HC）个体在神经状态转换时的皮层层级结构和纹状体活动改变有关。50名年龄较大的青少年和年轻人（29名TE，21名HC）在功能磁共振成像期间观看了电影《多云》。一种贪婪状态边界搜索算法评估了枕叶皮层和角回中神经状态转换的最佳事件数量、质量和划分一致性。在枕叶和角回诱发的神经状态转换时评估纹状体（伏隔核、尾状核和壳核）的活动。与HC相比，TE参与者在枕叶诱发的神经状态转换数量较少，而在角回诱发的神经状态转换数量较多。与HC相比，TE参与者在枕叶和角回皮层的神经状态划分解决方案质量也较低。此外，在角回诱发的神经状态转换时，TE参与者的壳核活动比HC少。这项研究为有症状的TE个体异常事件划分提供了神经生物学见解，揭示了影响创伤相关障碍中过度概括记忆的机制。
