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Updated: Mar 10, 2026

Measuring Neural Mechanisms Underlying Sleep-Dependent Memory Consolidation During Naps in Early Childhood
Published on: October 2, 2019
Mental time travel to the future might be reduced in sleep
Jana Speth1, Astrid M Schloerscheidt1, Clemens Speth1
1University of Dundee, School of Psychology, Dundee DD1 4HN, Scotland, UK.
Abstract:
We present a quantitative study of mental time travel to the future in sleep. Three independent, blind judges analysed a total of 563 physiology-monitored mentation reports from sleep onset, REM sleep, non-REM sleep, and waking. The linguistic tool for the mentation report analysis is based on established grammatical and cognitive-semantic theories and has been validated in previous studies. Our data indicate that REM and non-REM sleep must be characterized by a reduction in mental time travel to the future, which would support earlier physiological evidence at the level of brain function.
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