A single-session of mindfulness meditation expedites immediate motor memory consolidation to improve wakeful offline learning

Post-training meditation has been shown to promote wakeful motor memory stabilization in experienced meditators. We investigated the effect of single-session mindfulness meditation on wakeful and sleep-dependent forms of implicit motor memory consolidation in mediation naïve adults. Immediately after implicit sequence training, participants (N = 20, 8 females, Mage = 23.9 years ± 3.3) completed either a 10-minute focused attention meditation (N = 10), aiming to direct and sustain attention to breathing, or a control listening task. They were then exposed to interference through novel sequence training. Trained sequence performance was tested following a 5-hour wakeful period and again after a 15-hour period, which included sleep. Bayesian inference was applied to group comparison of mean reaction time (MRT) changes across training, interference, wakeful and post-sleep time points. Relative to control conditions, post-training meditation reduced novel sequence interference (BF10 = 6.61) and improved wakeful motor memory consolidation (BF10 = 8.34). No group differences in sleep consolidation were evident (BF10 = 0.38). These findings illustrate that post-training mindfulness meditation expedites wakeful offline learning of an implicit motor sequence in meditation naïve adults. Interleaving mindfulness meditation between acquisition of a target motor sequence and exposure to an interfering motor sequence reduced proactive and retroactive inference. Post-training mindfulness meditation did not enhance nor inhibit sleep-dependent offline learning of a target implicit motor sequence. Previous meditation training is not required to obtain wakeful consolidation gains from post-training mindfulness meditation.

Implicit Motor Imagery of the Foot and Hand in People with Achilles Tendinopathy: A Left Right Judgement Study

Objective To determine if impairment in motor imagery processes is present in Achilles tendinopathy (AT), as demonstrated by a reduced ability to quickly and accurately identify the laterality (left-right judgement) of a pictured limb. Additionally, this study aimed to use a novel data pooling approach to combine data collected at 3 different sites via meta-analytical techniques that allow exploration of heterogeneity. Design Multi-site case-control study. Methods Three independent studies with similar protocols were conducted by separate research groups. Each study-site evaluated left/right judgement performance for images of feet and hands using Recognise© software and compared performance between people with AT and healthy controls. Results from each study-site were independently collated, then combined in a meta-analysis. Results In total, 126 participants (40 unilateral, 22 bilateral AT cases, 61 controls) were included. There were no differences between AT cases and controls for hand image accuracy and reaction time. Contrary to the hypothesis, there were no differences in performance between those with AT and controls for foot image reaction time, however there were conflicting findings for foot accuracy, based on four separate analyses. There were no differences between the affected and unaffected sides in people with unilateral AT. Conclusions Impairments in motor imagery performance for hands were not found in this study, and we found inconsistent results for foot accuracy. This contrasts to studies in persistent pain of limbs, face and knee osteoarthritis, and suggests that differences in pathoetiology or patient demographics may uniquely influence proprioceptive representation.

Multiple bouts of high-intensity interval exercise reverse age-related functional connectivity disruptions without affecting motor learning in older adults

Exercise has emerged as an intervention that may mitigate age-related resting state functional connectivity and sensorimotor decline. Here, 42 healthy older adults rested or completed 3 sets of high-intensity interval exercise for a total of 23 min, then immediately practiced an implicit motor task with their non-dominant hand across five separate sessions. Participants completed resting state functional MRI before the first and after the fifth day of practice; they also returned 24-h and 35-days later to assess short- and long-term retention. Independent component analysis of resting state functional MRI revealed increased connectivity in the frontoparietal, the dorsal attentional, and cerebellar networks in the exercise group relative to the rest group. Seed-based analysis showed strengthened connectivity between the limbic system and right cerebellum, and between the right cerebellum and bilateral middle temporal gyri in the exercise group. There was no motor learning advantage for the exercise group. Our data suggest that exercise paired with an implicit motor learning task in older adults can augment resting state functional connectivity without enhancing behaviour beyond that stimulated by skilled motor practice.

Learning from the path not taken: Sensory prediction errors are sufficient for implicit adaptation of withheld movements

Current theories of motor control emphasize forward models as a critical component of the brain's motor execution and learning networks. These internal models are thought to predict the consequences of movement before sensory feedback from these movements can reach the brain, allowing for smooth, continuous online motor performance and for the computation of prediction errors that drive implicit motor learning. Taking this framework to its logical extreme, we tested the hypothesis that movements are not necessary for the generation of predictions, the computation of prediction errors, and implicit motor adaptation. Human participants were cued to move a computer mouse to a visually displayed target and were subsequently cued to withhold those movements on a subset of trials. Visual errors displayed on both trials with and without movements to the target induced single-trial learning. Furthermore, learning on trials without movements persisted when accompanying movement trials were never paired with errors and when movement and sensory feedback trajectories were decoupled. These data provide compelling evidence supporting an internal model framework in which forward models generate sensory predictions independent of the generation of movements.