Alham Al-Sharman

Performance on a functional motor task is enhanced by sleep in middle-aged and older adults.

Background and Purpose: Although sleep has been shown to enhance motor skill learning, it remains unclear whether sleep enhances learning of a functional motor task in middle-aged and older individuals. The purpose of this study was to examine whether sleep enhances motor learning of a functional motor task in middle-aged and older adults. Methods: Twenty middle-aged and 20 older individuals were randomly assigned to either the sleep condition or the no-sleep condition. Participants in the sleep condition practiced a novel walking task in the evening, and returned the following morning for retesting. Participants in the no-sleep condition practiced the walking task in the morning and returned the same day in the evening for a retest. Outcome measures included time around the walking path and spatiotemporal gait parameters. Results: Only the middle-aged and older adults in the sleep condition demonstrated significant off-line improvement in performance, measured as a decline in time to walk around the novel path and improvement in spatiotemporal gait parameters. The middle-aged and older adults in the no-sleep condition failed to demonstrate off-line improvements in performance of this functional task. Conclusions: This is the first study to provide evidence that sleep facilitates learning a clinically relevant functional motor task in middle-aged and older adults. Because many neurologic conditions occur in the middle-aged and older adults and sleep issues are very prevalent in many neurologic conditions, it is imperative that physical therapists consider sleep as a factor that may impact motor learning and recovery in these individuals. Video Abstract available. (See Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A73) for more insights from the authors.

Sleep Parameters, Functional Status, and Time Post-Stroke are Associated with Offline Motor Skill Learning in People with Chronic Stroke.

Background Mounting evidence demonstrates that individuals with stroke benefit from sleep to enhance learning of a motor task. While stage NREM2 sleep and REM sleep have been associated with offline motor skill learning in neurologically intact individuals, it remains unknown which sleep parameters or specific sleep stages are associated with offline motor skill learning in individuals with stroke. Methods Twenty individuals with chronic stroke (>6 months following stroke) and 10 control participants slept for three consecutive nights in a sleep laboratory with polysomnography. Participants practiced a tracking task the morning before the third night and underwent a retention test the morning following the third night. Offline learning on the tracking task was assessed. Pearson’s correlations assessed for associations between the magnitude of offline learning and sleep variables, age, upper-extremity motor function, stroke severity, depression, and time since stroke occurrence. Results Individuals with stroke performed with significantly less error on the tracking task following a night of sleep (p = 0.006) while the control participants did not (p = 0.816). Increased sleep efficiency (r = −0.285), less time spent in stage NREM3 sleep (r = 0.260), and more time spent in stage REM sleep (r = −0.266) were weakly-to-moderately associated with increased magnitude of offline motor learning. Furthermore, higher upper-extremity motor function (r = −0.400), lower stroke severity (r = 0.360), and less time since stroke occurrence (r = 0.311) were moderately associated with increased magnitude of offline motor learning. Conclusion This study is the first study to provide insight into which sleep stages and individual characteristics may be associated with offline learning in people with stroke. Further research is needed to delineate which factors or combination of factors promote offline motor learning in people with neurologic injury to best promote motor recovery in these individuals.

Sleep promotes offline enhancement of an explicitly learned discrete but not an explicitly learned continuous task.

Background Healthy young individuals benefit from sleep to promote offline enhancement of a variety of explicitly learned discrete motor tasks. It remains unknown if sleep will promote learning of other types of explicit tasks. The purpose of this study is to verify the role of sleep in learning an explicitly instructed discrete motor task and to determine if participants who practice an explicitly instructed continuous tracking task demonstrate sleep-dependent offline learning of this task. Methods In experiment 1, 28 healthy young adults (mean age 25.6 ± 3.8 years) practiced a serial reaction time (SRT) task at either 8 am (SRT no-sleep group) or 8 pm (SRT sleep group) and underwent retention testing 12 ± 1 hours later. In experiment 2, 20 healthy young individuals (mean age 25.6 ± 3.3 years) practiced a continuous tracking task and were similarly divided into a no-sleep (continuous tracking no-sleep group) or sleep group (continuous tracking sleep group). Individuals in both experiments were provided with explicit instruction on the presence of a sequence in their respective task prior to practice. Results Individuals in the SRT sleep group demonstrated a significant offline reduction in reaction time whereas the SRT no-sleep group did not. Results for experiment 1 provide concurrent evidence that explicitly learned discrete tasks undergo sleep-dependent offline enhancement. Individuals in the continuous tracking sleep group failed to demonstrate a significant offline reduction in tracking error. However, the continuous tracking no-sleep group did demonstrate a significant offline improvement in performance. Results for experiment 2 indicate that sleep is not critical for offline enhancement of an explicit learned continuous task. Conclusion The findings that individuals who practiced an explicitly instructed discrete task experienced sleep-dependent offline learning while those individuals who practiced an explicitly instructed continuous task did not may be due to the difference in motor control or level of complexity between discrete and continuous tasks.

Bilateral anodal transcranial direct current stimulation effect on balance and fearing of fall in patient with Parkinson’s disease

BACKGROUND A number of studies have examined the therapeutic effects of transcranial direct current stimulation (tDCS) stimulation in patients with Parkinsons disease (PD) using unilateral anodal stimulation applied either on the left or right brain hemisphere. However, PD involves the dysfunctions of both brain hemispheres. OBJECTIVES This study investigates the therapeutic effects of bilateral anodal tDCS stimulation on balance and fear of fall outcomes in patient with PD. METHODS Eighteen patients with idiopathic PD completed the study. Ten sessions of bilateral anodal tDCS stimulation were applied over the FC1 and FC2 targeting both pre-frontal and motor areas for each patient, 5 sessions per week for 2 weeks. Berg Balance Scale (BBS), Falls Efficacy Scale-International (FES-I), and 10 meters walk test (10mwt) were applied before and after the stimulation therapy. RESULTS Paired t-test showed a significant increase in the BBS scores and decrease in the FES-I scores after the bilateral tDCS compared with those scores before tDCS therapy (P < 0.05), as well improvement in the 10mwt scores. CONCLUSION Our data showed that bilateral anodal tDCS serves as an effective, safe and feasible approach for rehabilitation of patients with PD with the issues related to balance and fear of fall.

Sleep characteristics of individuals with chronic stroke: a pilot study

Changes in sleep characteristics in individuals with chronic stroke are not well described, particularly compared with healthy individuals. Therefore, the aim of this pilot study was to explore the sleep characteristics in individuals with chronic stroke compared to age- and sex-matched controls. Sixteen individuals with chronic stroke and ten age- and sex-matched controls underwent two nights of polysomnographic recording. The sleep characteristics of interest included total sleep time, sleep efficiency, and percent time, as well as time in minutes spent in stages N1, N2, and N3 and stage R sleep. The individuals with chronic stroke spent less percent time in stage N3 compared with controls (P=0.048). No significant differences in the other sleep characteristics were found between the stroke and control groups. Individuals with chronic stroke present with altered stage N3 sleep compared with healthy controls. These alterations in stage N3 sleep might be a sign of neuronal dysfunction and may impact recovery following stroke. A larger scale study is needed to confirm these findings.

Depression is a predictor for balance in people with multiple sclerosis

BACKGROUND Balance impairments are common and multifactorial among people with multiple sclerosis (MS). Depression is the most common psychological disorder in MS population and is strongly correlated with MS disease. Depression might be one of the factors that contribute to balance deficits in this population. However, the relationship between depression and balance impairments has not been explored in people with MS. OBJECTIVE To investigate the association between depression and balance impairments in people with MS. METHODS Cross sectional design was used in patients with MS. The Activities-specific Balance Confidence scale (ABC) and Berg Balance Scale (BBS) was used to assess balance. Beck Depression Inventory (BDI-II) was used to quantify depression and Kurtizki Expanded Disability Status Scale (EDSS) was utilized for the evaluation of MS disability severity. Pearson correlation coefficient was used to examine the association between depression and balance measurements. Multiple linear stepwise regressions were also conducted to find out if depression is a potential predictor for balance deficits. RESULTS Seventy-five individuals with MS (Female = 69%) with a mean age (SD) of 38.8 (10) and a mean (SD) EDSS score of 3.0 (1.4) were recruited in this study. Depression was present in 53% of the patients. Depression was significantly correlated with balance measurements and EDSS. However, multiple linear stepwise regressions found that only depression and age significantly predict balance. CONCLUSION Depression and balance were found frequent and associated in people with MS. Importantly depression was a significant predictor for balance impairments in individuals with MS. Balance rehabilitation may be hindered by depression. Therefore, depression should be evaluated and treated properly in individuals with MS.

Executive Function Is Associated With Off-Line Motor Learning in People With Chronic Stroke

Background and Purpose: Sleep has been shown to promote off-line motor learning in individuals following stroke. Executive function ability has been shown to be a predictor of participation in rehabilitation and motor recovery following stroke. The purpose of this study was to explore the association between executive function and off-line motor learning in individuals with chronic stroke compared with healthy control participants. Methods: Seventeen individuals with chronic stroke (>6 months poststroke) and 9 healthy adults were included in the study. Participants underwent 3 consecutive nights of polysomnography, practiced a continuous tracking task the morning of the third day, and underwent a retention test the morning after the third night. Participants underwent testing on 4 executive function tests after the continuous tracking task retention test. Results: Participants with stroke showed a significant positive correlation between the off-line motor learning score and performance on the Trail-Making Test from Delis-Kaplan Executive Function System (r = 0.652; P = 0.005), while the healthy control participants did not. Regression analysis showed that the Trail-Making Test–Delis-Kaplan Executive Function System is a significant predictor of off-line motor learning (P = 0.008). Discussion and Conclusions: This is the first study to demonstrate that better performance on an executive function test of attention and set-shifting predicts a higher magnitude of off-line motor learning in individuals with chronic stroke. This emphasizes the need to consider attention and set-shifting abilities of individuals following stroke as these abilities are associated with motor learning. This in turn could affect learning of activities of daily living and impact functional recovery following stroke. Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A166).

Sleep-Dependent Learning of a Functional Motor Task Declines with Age

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