Department of Integrative Medical Biology Physiology), Umeå University, 90187 Umeå, Sweden.
Proc Natl Acad Sci U S A. 2010 Dec 21;107(51):22356-9. doi: 10.1073/pnas.1016823108. Epub 2010 Dec 6.
"Mental time travel" refers to conscious experience of remembering the personal past and imagining the personal future. Little is known about its neural correlates. Here, using functional magnetic resonance imaging, we explored the hypothesis that mental time travel into "nonpresent" times (past and future) is enabled by a special conscious state (chronesthesia). Well-trained subjects repeatedly imagined taking one and the same short walk in a familiar environment, doing so either in the imagined past, present, or future. In an additional condition, they recollected an instance in which they actually performed the same short walk in the same familiar setting. This design allowed us to measure brain activity correlated with "pure" conscious states of different moments of subjective time. The results showed that the left lateral parietal cortex was differentially activated by nonpresent subjective times compared with the present (past and future > present). A similar pattern was observed in the left frontal cortex, cerebellum, and thalamus. There was no evidence that the hippocampal region is involved in subjective time travel. These findings provide support for theoretical ideas concerning chronesthesia and mental time travel.
“心理时间旅行”是指有意识地回忆个人过去和想象个人未来的体验。目前对于其神经关联知之甚少。在这里，我们使用功能磁共振成像技术，探索了这样一个假设，即进入“非现在”时间（过去和未来）的心理时间旅行是由一种特殊的意识状态（时间感）所实现的。经过训练的受试者反复想象在熟悉的环境中进行一次相同的短距离散步，分别在想象中的过去、现在或未来进行。在另外一个条件下，他们回忆起在同一个熟悉的环境中实际进行同样短距离散步的一个实例。这个设计使我们能够测量与不同主观时间点的“纯”意识状态相关的大脑活动。结果表明，与现在相比，左外侧顶叶皮层在非现在的主观时间上的激活程度不同（过去和未来>现在）。在左额叶皮层、小脑和丘脑也观察到了类似的模式。没有证据表明海马区参与了主观时间旅行。这些发现为关于时间感和心理时间旅行的理论观点提供了支持。
