Abstract
The acquisition and retention of motor skills is necessary for everyday functioning in the elderly and may be critical in the context of motor rehabilitation. Recent studies indicate that motor training closely followed by sleep may result in better engagement of procedural (“how to”) memory consolidation processes in the elderly. Nevertheless, elderly individuals are mostly morning oriented and a common practice is to time rehabilitation programs to morning hours. Here, we tested whether the time-of-day wherein training is afforded (morning, 8–10:30 a.m., or evening, 6–9 p.m.) affects the long-term outcome of a multi-session motor practice program (10 sessions across 3–4 weeks) in healthy elderly participants. Twenty-nine (15 women) older adults (60–75 years) practiced an explicitly instructed five-element key-press sequence by repeatedly generating the sequence “as fast and accurately as possible.” The groups did not differ in terms of sleep habits and quality (1-week long actigraphy); all were morning-oriented individuals. All participants gained robustly from the intervention, shortening sequence tapping duration and retaining the gains (> 90%) at 1-month post-intervention, irrespective of the time-of-day of training. However, retesting at 7-months post-intervention showed that the attrition of the training induced gains was more pronounced in the morning trained group compared to the evening group (76 and 56.5% loss in sequence tapping time; 7/14 and 3/14 participants showed a > 5% decline in accuracy relative to end of training, respectively). Altogether, the results show that morning-oriented older adults effectively acquired skill in the performance of a sequence of finger movements, in both morning and evening practice sessions. However, evening training leads to a significant advantage, over morning training, in the long-term retention of the skill. Evening training should be considered an appropriate time window for motor skill learning in older adults, even in individuals with morning chronotype. The results are in line with the notion that motor training preceding a sleep interval may be better consolidated into long-term memory in the elderly, and thus result in lower forgetting rates.
Highlights
Motor functioning and, the ability of older adults to acquire new fine motor skills and generate effective longterm procedural (“how to”) memory are often reduced compared to young adults (Voelcker-Rehage, 2008)
Using the well-established paradigm of the finger tapping sequence learning (FTSL) task (Karni et al, 1995, 1998), we investigated whether the time-of-day wherein training is afforded is a significant factor in motor skill acquisition, the ability to generalize the gains in performance, and importantly, the retention of the skill, in healthy elderly participants
We tested whether the time-of-day wherein training was afforded during a multi-session motor training program affects the acquisition and mastering of a movement sequence or the long-term
Summary
The ability of older adults to acquire new fine motor skills and generate effective longterm procedural (“how to”) memory are often reduced compared to young adults (Voelcker-Rehage, 2008). The decline in motor learning abilities was suggested to reflect a general decrease in neuroplasticity with aging (King et al, 2013), or stricter control (“gating”) of the brain’s plasticity mechanisms subserving procedural long-term memory (Korman et al, 2015), or both. The latter notion implies that in specific biobehavioral conditions, devised to meet the age-related constraints on plasticity, the potential of older adults to master motor skills may be better expressed. Recent studies suggest that time-of-day effects may differ across cognitive domains (Schmidt et al, 2015); implicit memory retrieval may, be better at offpeak than at peak alertness hours in both young and elderly (May et al, 2005)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
