Sleep Restores The Potential To Undergo Learning Induced Increases Of Corticomotor Excitability: New Evidence In Line With The Synaptic Downscaling Hypothesis

Abstract

Event Abstract Back to Event Sleep Restores The Potential To Undergo Learning Induced Increases Of Corticomotor Excitability: New Evidence In Line With The Synaptic Downscaling Hypothesis Toon De Beukelaar1, Jago Van Soom1 and Nicole Wenderoth2* 1 Catholic University of Leuven, Department of Kinesiology, Belgium 2 ETH Zurich, Department of Health Sciences and Technology, Switzerland "Synaptic downscaling" is hypothesized to be an important process during sleep such that previously potentiated synapses are reset. This is necessary for the acquisition of new memories during subsequent wakefulness. Even though synaptic downscaling is an appealing concept, there is little experimental evidence available in humans. Here we measured training-induced changes in corticomotor excitability as a marker for a person's capacity to undergo neuroplastic changes. In accordance with synaptic downscaling, we hypothesized that the neuroplastic potential would be reduced in the evening, but would be restored again after one night of sleep. Subjects (n=19) were assigned to one of two groups: the WAKE-group acquired a 5-element sequence at 8am and a different sequence at 8pm after a day awake, while the SLEEP-group first learned a sequence at 8pm and a second at 8am after a night of sleep. Neuroplasticity was quantified by measuring Input-Output (I/O) curves with transcranial magnetic stimulation (TMS) before and after the learning task. In the WAKE-group, repeated measures ANOVA revealed a significantly larger increase from pre- to post-learning in the morning than evening. Moreover, pre-learning excitability was higher in the evening than morning (p<.05). In the SLEEP-group, the opposite pattern of neuroplasticity was observed (p<.05) such that changes from pre- to post-learning were smaller in the evening than morning when tested after a sufficient amount of sleep. Behaviorally both groups improved significantly during training with no differences between groups or between learning sessions. In conclusion, our neural data are in line with the synaptic downscaling hypothesis and provide new evidence on the interaction between sleep and neuroplasticity. However, these neural effects were subtle and were not reflected in behavioral estimates of motor memory formation. Keywords: Sleep, Transcranial Magnetic Stimulation, motor learning, consolidation, Finger Sequence Task, Synaptic Downscaling Conference: XII International Conference on Cognitive Neuroscience (ICON-XII), Brisbane, Queensland, Australia, 27 Jul - 31 Jul, 2014. Presentation Type: Poster Topic: Memory and Learning Citation: De Beukelaar T, Van Soom J and Wenderoth N (2015). Sleep Restores The Potential To Undergo Learning Induced Increases Of Corticomotor Excitability: New Evidence In Line With The Synaptic Downscaling Hypothesis. Conference Abstract: XII International Conference on Cognitive Neuroscience (ICON-XII). doi: 10.3389/conf.fnhum.2015.217.00176 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 19 Feb 2015; Published Online: 24 Apr 2015. * Correspondence: Prof. Nicole Wenderoth, ETH Zurich, Department of Health Sciences and Technology, Zurich, Switzerland, nicole.wenderoth@hest.ethz.ch Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Toon De Beukelaar Jago Van Soom Nicole Wenderoth Google Toon De Beukelaar Jago Van Soom Nicole Wenderoth Google Scholar Toon De Beukelaar Jago Van Soom Nicole Wenderoth PubMed Toon De Beukelaar Jago Van Soom Nicole Wenderoth Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.