Mental representation of autobiographical memories along the sagittal mental timeline: Evidence from spatiotemporal interference

Abstract

Time is usually conceived of in terms of space: many natural languages refer to time according to a back-to-front axis. Indeed, whereas the past is usually conceived to be "behind us", the future is considered to be "in front of us." Despite temporal coding is pivotal for the development of autonoetic consciousness, little is known about the organization of autobiographical memories along this axis. Here we developed a spatial compatibility task (SCT) to test the organization of autobiographical memories along the sagittal plane, using spatiotemporal interference. Twenty-one participants were asked to recall both episodic and semantic autobiographical memories (EAM and SAM, respectively) to be used in the SCT. Then, during the SCT, they were asked to decide whether each event occurred before or after the event presented right before, using a response code that could be compatible with the back-to-front axis (future in front) or not (future at back). We found that performance was significantly worse during the non-compatible condition, especially for EAM. The results are discussed in light of the evidence for spatiotemporal encoding of episodic autobiographical memories, taking into account possible mechanisms explaining compatibility effects.

Keywords: Episodic memory; Mental time travel; Mental timeline; Semantic memory; Spatiotemporal interference.

Fig. 1

Experimental timeline and conditions. Compatible (A) and non-compatible (B) conditions of EAM are shown in the left panels. Compatible (C) and non-compatible (D) conditions of SAM are shown in the right panels. EAM episodic autobiographical memory, SAM semantic autobiographical memory

Fig. 2

Results of the spatial compatibility task. Accuracy is shown on the left, whereas response times are shown on the right. EAM episodic autobiographical memory, SAM semantic autobiographical memory, C compatible, NC non-compatible