ABSTRACT

Introduction: The automatic interaction between a cue and a memory trace can give rise to the vivid recollection of a purely sensory past experience. But are humans able to reach back intentionally to purely sensory experiences in the absence of any exogenous or endogenous cue? In the present study, we propose an alternative hypothesis, claiming that the retrieval of associated semantic memories, stored in the left hemisphere and acting as endogenous cues, is a prerequisite for intentionally recollecting sensory experience stored in the right hemisphere during mental time travels (MTT).

Methods: To investigate this issue, we administered an MTT task to 26 epileptic patients (16 males and 10 females) who had undergone right or left temporal lobectomy and to 28 age and education matched controls. The task was devised so as to require the recollection of purely visual memories in the absence of external cues. Participants also performed two conventional recognition tasks with visual and verbal materials. The three between-subjects memory tasks were analyzed separately with the Kruskal-Wallis test and the Wilcoxon rank-sum test in order to investigate differences across groups. According to our hypothesis, we expected side asymmetries in the patients’ performance on the two recognition tasks but not the MTT task.

Results: While patients showed the well-known hemispheric asymmetry for visual and verbal material in the (external-cue dependent) recognition tasks, no side asymmetries emerged in the purely visual MTT task.

Conclusions: In keeping with the view that visual memories cannot be targeted directly by a strategic search process, the lack of any side asymmetry in our MTT task can be interpreted as a trade-off between left-sided strategic search for associated semantic memories and right-sided storage of visual ones.

摘要

简介：提示和记忆轨迹之间的自动交互可以使您对过去的纯粹感官体验产生生动的回忆。但是，在没有任何外在或内在线索的情况下，人类是否能够有意识地退回到纯粹的感官体验？在本研究中，我们提出了另一种假设，声称检索存储在左半球并作为内源线索的相关语义记忆是在心理时间旅行期间有意回收存储在右半球的感官体验的前提（MTT） ）。

方法：为调查此问题，我们对26例接受了右或左颞叶切除术的癫痫患者（16例男性和10例女性）以及28例年龄和文化程度相匹配的对照组进行了MTT任务。设计任务是为了在没有外部提示的情况下要求回忆纯视觉记忆。参与者还使用视觉和言语材料执行了两个常规的识别任务。为了调查各组之间的差异，分别使用Kruskal-Wallis检验和Wilcoxon秩和检验分别分析了三个受试者之间的记忆任务。根据我们的假设，我们期望患者在两个识别任务上的表现不对称，而在MTT任务上则不会。

结果：虽然患者在（依赖外部提示）识别任务中显示出众所周知的视觉和言语物质半球不对称性，但在纯粹的视觉MTT任务中未出现侧面不对称性。

结论：鉴于视觉记忆不能通过战略搜索过程直接作为目标的观点，我们的MTT任务中缺乏任何侧面不对称性可以解释为在针对关联语义记忆的左侧战略搜索与右战略搜索之间的权衡。视觉存储。