In mental time travel (MTT) one is “traveling” back-and-forth in time, remembering, and imagining events. Despite intensive research regarding memory processes in the hippocampus, it was only recently shown that the hippocampus plays an essential role in encoding the temporal order of events remembered, and therefore plays an important role in MTT. Does it also encode the temporal relations of these events to the remembering self? We asked patients undergoing pre-surgical evaluation with depth electrodes penetrating the temporal lobes bilaterally toward the hippocampus to project themselves in time to a past, future, or present time-point, and then make judgments regarding various events. Classification analysis of intracranial evoked potentials revealed clear temporal dissociation in the left hemisphere between lateral-temporal electrodes, activated at ∼100–300ms, and hippocampal electrodes, activated at ∼400–600ms. This dissociation may suggest a division of labor in the temporal lobe during self-projection in time, hinting toward the different roles of the lateral-temporal cortex and the hippocampus in MTT and the temporal organization of the related events with respect to the experiencing self.
Bibliographical noteFunding Information:
We would like to thank our patients for their kind agreement to participate in the study. MN is grateful to the Azrieli Foundation for the award of an Azrieli Fellowship.
The study was supported by the Israel Science Foundation and the Agnes Ginges Center for Neurogenetics.
© 2018 Schurr, Nitzan, Eliahou, Spinelli, Seeck, Blanke and Arzy.
- Episodic memory
- Lateral temporal
- Mental time travel