The "Mnemonic Time-Travel Effect"

This registered report aims at replicating the so-called "mnemonic time-travel" effect. Aksentijevic, Brandt, Tsakanikos, and Thorpe (2019) reported that memory was improved when their participants experienced backward motion before a memory test in comparison to when they experienced forward motion or no motion. This finding was interpreted as suggesting that backward motion brought individuals back to the moment of encoding. In the original study, the mnemonic time-travel effect was robustly found with various types of backward motion (real, simulated, and imagined). Such a spectacular finding calls for a preregistered replication. To determine the robustness of the effect, we performed a close replication of Experiment 4 of Aksentijevic et al. in which the mnemonic time-travel effect was most pronounced. Despite sufficient statistical power to detect an even considerably smaller effect than the one reported by Aksentijevic et al., we found no significant differences among the different motion conditions. The present results thus disconfirm the idea that experiencing backward motion improves memory which suggests that the empirical robustness of the mnemonic time travel effect should be further scrutinized before any conclusions about mnemonic space and time can be drawn.