Transcranial Direct Current Stimulation of Supplementary Motor Region Impacts the Effectiveness of Interleaved and Repetitive Practice Schedules for Retention of Motor Skills

Commentary: Variability of Practice, Information Processing, and Decision Making—How Much Do We Know?

“…In contrast, learning from RP has been reported to involve more extensive activation of parts of the default network often associated with mind-wandering (Wymbs and Grafton, 2009 ). The importance of planning activity involving some of these regions (i.e., SMA, M1) has been verified using non-invasive stimulation to upregulate activity at these sites during RP leading to improved retention (Kim and Wright, 2020 ; Kim et al, 2021 ). Taken together, these data are consistent with the basic tenet of the forgetting-reconstruction account.…”

A multi-representation approach to the contextual interference effect: effects of sequence length and practice

“…Another limitation of the present study is the use of a 24-h retention interval. A few studies showed that the retention benefit of RP continued to increase across successive days (Kim & Wright, 2020;Walker et al, 2003aWalker et al, , 2003bWalker et al, 2003aWalker et al, , 2003b. This was especially due to RP resisting the typical forgetting over days that is observed after BP.…”

Exposure to Sleep, Rest, or Exercise Impacts Skill Memory Consolidation but so Too Can a Challenging Practice Schedule

“…Anodal stimulation (e.g., 1 mA for 20 min) is a condition in which the anode is placed over the neural region being targeted resulting in an upregulation of activity at the stimulated site (e.g., M1) reflected in an increased MEP from the application of single-pulse TMS compared with sham stimulation ( E ). Applying anodal tDCS at right M1 while the learner performed a motor sequence task with the left hand during RP results in offline gains rather than the anticipated loss in performance commonly observed following RP when performed in the absence of stimulation ( Kim and Wright, 2020 ; F ).…”

“…Finally, it is critical to highlight that offline enhancement garnered via IP is not restricted to retention that is evaluated after 24 h or longer during which the learner is privy to overnight sleep as is the case for the influence of acute exercise for offline gain ( Jo et al, 2019 ). Performance facilitation from IP has also been observed during tests administered as early as 6 h following the termination of practice as well as during the more common time frames used to assess memory, typically up to 72 h, when sleep-related consolidation might also contribute to any reported benefits ( Kim and Wright, 2020 ). These data are important because they implicate practice organization, specifically IP, as a means to mediate postpractice consolidation independent of the powerful impact induced from exposure to sleep.…”

“…It is important to note these data do not necessarily imply that the neural substrates supporting the effects of these different interventions are (1) restricted to just M1 or (2) involve the same neural substrates. Indeed, there are recent data indicating that exogenous stimulation using tDCS of neural sites beyond M1 during RP can mediate the nature of offline changes in performance ( Kim and Wright, 2020 ). At this juncture then, the extant data suggest that, much like the case for sleep and exercise, the implementation of consolidation following IP that moves skill memory from its initial labile to more stable or even enhanced form is linked to heightened activity at M1 or maybe more broadly in neural circuitry incorporating M1.…”