Cognition and Brain Plasticity Group, Institute of Biomedicine Research of Bellvitge (IDIBELL), Spain; Department of Cognitive, Developmental and Educational Psychology, University of Barcelona, Spain; Institute of Neurosciences, University of Barcelona, Spain.
VA Boston Healthcare System Neuroimaging Research for Veterans Center (NeRVe) and the Memory Disorders Research Center, United States; Department of Psychiatry, Boston University School of Medicine, United States.
Neuropsychologia. 2018 Feb;110:7-13. doi: 10.1016/j.neuropsychologia.2017.08.020. Epub 2017 Aug 16.
The subjective sense of recollecting events from one's past is an essential feature of episodic memory, but the neural mechanisms supporting this capacity are poorly understood. We examined the role of large-scale patterns of neural synchrony using whole-head MEG recordings in healthy adults and S.M., who has severely deficient autobiographical memory (SDAM; Palombo et al., 2015), a syndrome in which autobiographical recollection is absent but other functions (including other mnemonic functions), are normal. MEG was conducted while participants listened to prospectively collected recordings documenting unique personal episodes (PE) that normally evoke rich recollection, as well as a condition including general semantic information that is non-specific in place or time (GS; Levine et al., 2004). We predicted that PE (and not GS) would be associated with changes in patterns of large-scale neural synchrony in comparison subjects. We found large-scale neural synchrony, specifically in the gamma frequency ranges (i.e., 27-45Hz), specific to PE and not GS. These synchrony differences between PE and GS were not apparent in S.M. Our findings provide empirical evidence for the supporting role of large-scale gamma neural synchrony underlying autobiographical recollection.
从过去事件中回忆的主观感觉是情景记忆的一个基本特征，但支持这种能力的神经机制还了解甚少。我们使用全头 MEG 记录检查了大规模神经同步模式的作用，参与者包括健康成年人和 S.M.，S.M. 患有严重的自传体记忆缺陷（SDAM；Palombo 等人，2015），这种综合征中没有自传体回忆，但其他功能（包括其他记忆功能）正常。MEG 是在参与者听前瞻性收集的记录时进行的，这些记录记录了通常会引起丰富回忆的独特个人事件（PE），以及包括位置和时间上不特定的一般语义信息的条件（GS；Levine 等人，2004）。我们预测，与比较对象相比，PE（而不是 GS）会与大规模神经同步模式的变化相关。我们发现，PE （而非 GS）具有特定的大规模神经同步，特别是在伽马频带（即 27-45Hz）。PE 和 GS 之间的这些同步差异在 S.M. 中并不明显。我们的发现为支持自传体回忆的大规模伽马神经同步提供了经验证据。
