The chronology of events in time–space is naturally available to the senses, and the spatial and temporal dimensions of events entangle in episodic memory when navigating the real world. The mapping of time–space during navigation in both animals and humans implicates the hippocampal formation. Yet, one arguably unique human trait is the capacity to imagine mental chronologies that have not been experienced but may involve real events—the foundation of causal reasoning. Herein, we asked whether the hippocampal formation is involved in mental navigation in time (and space), which requires internal manipulations of events in time and space from an egocentric perspective. To address this question, we reanalyzed a magnetoencephalography data set collected while participants self-projected in time or in space and ordered historical events as occurring before/after or west/east of the mental self [Gauthier, B., Pestke, K., & van Wassenhove, V. Building the arrow of time… Over time: A sequence of brain activity mapping imagined events in time and space. Cerebral Cortex, 29, 4398–4414, 2019]. Because of the limitations of source reconstruction algorithms in the previous study, the implication of hippocampus proper could not be explored. Here, we used a source reconstruction method accounting explicitly for the hippocampal volume to characterize the involvement of deep structures belonging to the hippocampal formation (bilateral hippocampi [hippocampus proper], entorhinal cortices, and parahippocampal cortex). We found selective involvement of the medial temporal lobes (MTLs) with a notable lateralization of the main effects: Whereas temporal ordinality engaged mostly the left MTL, spatial ordinality engaged mostly the right MTL. We discuss the possibility of a top–down control of activity in the human hippocampal formation during mental time (and space) travels.

时空事件的年代顺序对感官来说是自然可用的，并且在导航现实世界时，事件的空间和时间维度纠缠在情节记忆中。动物和人类在导航过程中的时空映射都涉及海马体的形成。然而，一个可以说是独一无二的人类特征是能够想象尚未经历过但可能涉及真实事件的心理年表——因果推理的基础。在这里，我们询问海马体的形成是否涉及时间（和空间）的心理导航，这需要从自我中心的角度对时间和空间中的事件进行内部操纵。为了回答这个问题，大脑皮层，29, 4398–4414, 2019]。由于先前研究中源重建算法的局限性，无法探讨海马体本身的含义。在这里，我们使用了一种明确考虑海马体积的源重建方法来表征属于海马结构的深层结构（双侧海马 [海马体]、内嗅皮层和海马旁皮层）的参与。我们发现内侧颞叶 (MTL) 的选择性参与具有显着的主要影响的偏侧化：虽然时间顺序主要与左侧 MTL 相关，但空间顺序主要与右侧 MTL 相关。我们讨论了在精神时间（和空间）旅行期间自上而下控制人类海马结构活动的可能性。