Abstract：
Studies of the impact of brain injury on memory processes often focus on the quantity and episodic richness of those recollections. Here, we argue that the organization of one\'s recollections offers critical insights into the impact of brain injury on functional memory. It is well-established in studies of word list memory that free recall of unrelated words exhibits a clear temporal organization. This temporal contiguity effect refers to the fact that the order in which word lists are recalled reflects the original presentation order. Little is known, however, about the organization of recall for semantically rich materials, nor how recall organization is impacted by hippocampal damage and memory impairment. The present research is the first study, to our knowledge, of temporal organization in semantically rich narratives in three groups: (1) Adults with bilateral hippocampal damage and severe declarative memory impairment, (2) adults with bilateral ventromedial prefrontal cortex (vmPFC) damage and no memory impairment, and (3) demographically matched non-brain-injured comparison participants. We find that although the narrative recall of adults with bilateral hippocampal damage reflected the temporal order in which those narratives were experienced above chance levels, their temporal contiguity effect was significantly attenuated relative to comparison groups. In contrast, individuals with vmPFC damage did not differ from non-brain-injured comparison participants in temporal contiguity. This pattern of group differences yields insights into the cognitive and neural systems that support the use of temporal organization in recall. These data provide evidence that the retrieval of temporal context in narrative recall is hippocampal-dependent, whereas damage to the vmPFC does not impair the temporal organization of narrative recall. This evidence of limited but demonstrable organization of memory in participants with hippocampal damage and amnesia speaks to the power of narrative structures in supporting meaningfully organized recall despite memory impairment.
摘要：
脑损伤对记忆过程的影响的研究通常集中在这些回忆的数量和情节丰富度上。这里,我们认为，一个人的记忆的组织提供了关键的见解，脑损伤对功能记忆的影响。在单词列表记忆的研究中，已经确立了对无关单词的自由回忆具有清晰的时间组织。该时间邻接效应指的是单词列表被召回的顺序反映了原始呈现顺序的事实。鲜为人知，然而,关于语义丰富的材料的召回组织，海马损伤和记忆障碍如何影响回忆组织。本研究是第一项研究，根据我们的知识，在三组中，语义上丰富的叙事中的时间组织：（1）患有双侧海马损伤和严重的陈述性记忆障碍的成年人，(2)成人双侧腹内侧前额叶皮质(vmPFC)损害,无记忆障碍,和（3）人口统计学匹配的非脑损伤比较参与者。我们发现，尽管双侧海马损伤的成年人的叙事回忆反映了这些叙事经历的时间顺序高于机会水平，与对照组相比,它们的时间连续性效应显著减弱.相比之下,有vmPFC损伤的个体与非脑损伤的对比参与者在时间连续性上没有差异.这种群体差异模式产生了对认知和神经系统的见解，这些认知和神经系统支持在回忆中使用时间组织。这些数据提供了证据，表明叙事回忆中时间上下文的检索是海马依赖性的，而对vmPFC的损害不会损害叙事回忆的时间组织。海马损伤和健忘症参与者的记忆组织有限但可证明的证据表明，尽管记忆受损，叙事结构仍可支持有意义的有组织的回忆。
