Facilitation of human long-term memory with post learning physical exercise: an exploratory fMRI study
No Thumbnail Available
The Synaptic Tagging and Capture (STC)-hypothesis has put forward a rationale of how memory consolidation takes place on the cellular level, based on numerous animal studies. Research has demonstrated the importance of dopaminergic and noradrenergic activation and time for the late phase of consolidation. Post-learning interventions are believed to be effective when applied within two hours after learning. These predictions of the STC-hypothesis have yet to be tested in hu mans. lnterestingly, exercise is believed to have a net positive effect on neuronal plasticity and consequently memory, due to associations with acute neural and systemic up-regulations of dopamine and noradrenalin signalling. Therefore, this exploratory study made use of the physiological effects of acute exercise to test the predictions of the STC-hypothesis in humans. 48 healthy young adults were included in a between-subject design with fMRI measurements during memory retrieval two days after learning. Participants were randomly assigned to two experimental groups, performing exercise immediately after learning or after a 4 hour delay. Exercise consisted of a single-bout of sub-maxima! bicycle interval training. We find that delayed compared to immediate physical exercise after learning leads to better memory retention two days later. Furthermore, delayed exercise was associated with greater prefrontal activation during retrieval at this time. This exploratory study therefore suggests that exercise effects on memory are variable and follow a different time-course in animals and humans. Further research using post-learning interventions to test the STC-hypothesis in hu mans is necessary to unravel critica! features in memory consolidation.
Faculteit der Sociale Wetenschappen