Motor Learning in People with Multiple Sclerosis: A Systematic Review and Meta-analysis

Happy facial emotional congruence in patients with relapsing-remitting multiple sclerosis

BACKGROUND

Emotion categorization has often been studied in the relapsing-remitting form of multiple sclerosis (RR-MS), suggesting an impairment in the recognition of emotions. The production of facial emotional expressions in RR-MS has not been considered, despite their importance in non-verbal communication.

METHOD

Twenty-five RR-MS patients and twenty-five matched controls completed a task of emotional categorization during which their faces were filmed. The stimuli were dynamic (sound or visual), expressed by adults (women or men), and expressing happy (laughing or smiling) or negative emotion. Two independent blinded raters quantified the happy facial expressions produced. The categorization task was used as a proxy for emotional categorization, while the happy facial expressions produced assessed the production of emotions.

RESULTS

The main analysis indicated impaired categorization of RR-MS for happy stimuli selectively, whereas their happy facial expressions were not statistically different from those of the control group. More specifically, this group effect was found for smiles (and not laughter) and for happy stimuli produced by men. Analysis of individual patient profiles suggested that 77% of patients with impaired judgments produced normal facial expressions, suggesting a high prevalence of this dissociation. Only 8% of our samples showed reverse dissociation, with happy facial expressions significantly different from those of the control group and normal emotional judgments.

CONCLUSION

These results corroborated the high prevalence of emotional categorization impairment in RR-MS but not for negative stimuli, which can probably be explained by the methodological specificities of the present work. The unusual impairment found for happy stimuli (for both emotional categorization and facial congruence) may be linked to the intensity of the perceived happy expressions but not to the emotional valence. Our results also indicated a mainly preserved production of facial emotions, which may be used in the future sociocognitive care of RR-MS patients with impaired emotional judgments.

Explicit and implicit abilities in humor processing in patients with relapsing-remitting multiple sclerosis

Sociocognitive impairment is well known in the relapsing-remitting form of multiple sclerosis (RR-MS). The purpose of the present study was to assess explicit and implicit humor abilities in this population. Based on clinical observation and contrary to the current cognitive model, we hypothesized that implicit performances (happy facial expressions) would be better than explicit ones (humor judgment assessed by explicit humor comprehension, subjective feeling of amusement as a conscious appreciation of funniness, and verbal justifications of funniness). Twenty-five RR-MS patients and twenty-five healthy participants completed the tasks. Their face was filmed during humor ratings. Patients' results suggest that 32% of them showed an impairment in explicit humor comprehension, with normal facial expressions. Both groups found great difficulty in justifying the cause of their amusement. All these results may suggest the existence of a supplementary implicit pathway in humor processing. The preservation of this implicit pathway may be advantageous for future remediation. Contrary to the current model, we found that the subjective feeling of amusement was preserved when comprehension was impaired. Further studies will be needed to clarify this component, and adjust the theoretical modeling.

Electromyographic biofeedback-driven gaming to alter calf muscle activation during gait in children with spastic cerebral palsy

BACKGROUND

Children with cerebral palsy often show deviating calf muscle activation patterns during gait, with excess activation during early stance and insufficient activation during push-off.

RESEARCH QUESTION

Can children with cerebral palsy improve their calf muscle activation patterns during gait using one session of biofeedback-driven gaming?

METHODS

Eighteen children (6-17 y) with spastic cerebral palsy received implicit game-based biofeedback on electromyographic activity of the calf muscle (soleus or gastrocnemius medialis) while walking on a treadmill during one session. Biofeedback alternately aimed to reduce early stance activity, increase push-off activity, and both combined. Early stance and push-off activity and the double-bump-index (early stance divided by push-off activity) were determined during baseline and walking with feedback. Changes were assessed at group level using repeated measures ANOVA with simple contrast or Friedman test with post-hoc Wilcoxon signed rank test, as well as individually using independent t-tests or Wilcoxon rank sum tests. Perceived competence and interest-enjoyment were assessed through a questionnaire.

RESULTS

Children successfully decreased their electromyographic activity during early stance feedback trials (relative decrease of 6.8 ± 12.2 %, P = 0.025), with a trend during the combined feedback trials (6.5 ± 13.9 %, P = 0.055), and increased their electromyographic activity during push-off feedback trials (8.1 ± 15.8 %, P = 0.038). Individual improvements were seen in twelve of eighteen participants. All children experienced high levels of interest-enjoyment (8.4/10) and perceived competence (8.1/10).

SIGNIFICANCE

This exploratory study suggests that children with cerebral palsy can achieve small within-session improvements of their calf muscle activation pattern when provided with implicit biofeedback-driven gaming in an enjoyable manner. Follow-up gait training studies can incorporate this method to assess retention and long-term functional benefits of electromyographic biofeedback-driven gaming.

Cognitive-Motor Interference and Cortical Activation While Walking in Individuals With Multiple Sclerosis

The present study expands on current understanding of dual-task cognitive-motor interference, by including cortical activation measures to both traditional and ecologically valid dual-task paradigms. Fifteen individuals with multiple sclerosis and 14 control participants underwent mobility testing while wearing functional near-infrared spectroscopy. In the absence of increased prefrontal cortical activation, subjects with multiple sclerosis performed significantly worse on measures of cognition under both single- and dual-task conditions. These findings suggest that persons with multiple sclerosis may be unable to allocate additional cortical resources to cognition under dual-task conditions, leading to significant cognitive-motor interference and decrements in performance. This study is the first to investigate cortical activation across several commonly used and ecologically valid dual-task assessments.

The impact of aerobic and resistance training intensity on markers of neuroplasticity in health and disease

OBJECTIVE

To determine the effects of low- vs. high-intensity aerobic and resistance training on motor and cognitive function, brain activation, brain structure, and neurochemical markers of neuroplasticity and the association thereof in healthy young and older adults and in patients with multiple sclerosis, Parkinson's disease, and stroke.

DESIGN

Systematic review and robust variance estimation meta-analysis with meta-regression.

DATA SOURCES

Systematic search of MEDLINE, Web of Science, and CINAHL databases.

RESULTS

Fifty studies with 60 intervention arms and 2283 in-analyses participants were included. Due to the low number of studies, the three patient groups were combined and analyzed as a single group. Overall, low- (g=0.19, p = 0.024) and high-intensity exercise (g=0.40, p = 0.001) improved neuroplasticity. Exercise intensity scaled with neuroplasticity only in healthy young adults but not in healthy older adults or patient groups. Exercise-induced improvements in neuroplasticity were associated with changes in motor but not cognitive outcomes.

CONCLUSION

Exercise intensity is an important variable to dose and individualize the exercise stimulus for healthy young individuals but not necessarily for healthy older adults and neurological patients. This conclusion warrants caution because studies are needed that directly compare the effects of low- vs. high-intensity exercise on neuroplasticity to determine if such changes are mechanistically and incrementally linked to improved cognition and motor function.

The Role of Cognitive Impairment on Physical Therapy Attendance and Outcomes in Multiple Sclerosis

BACKGROUND AND PURPOSE

Many persons with multiple sclerosis (PwMS) experience cognitive impairments, which may affect their ability to engage in physical therapy. There is limited information on how cognitive impairments are associated with PwMS' ability to participate and improve their functional outcomes. This study aimed to assess the relationship between cognitive functioning and PwMS' attendance, total goal attainment, and functional improvement following physical therapy intervention.

METHODS

Participants (n = 45) were PwMS who participated in a larger self-management study and enrolled in physical therapy within the past 2 years. Objective cognitive functioning was examined using tests of prospective memory, retrospective memory, working memory, and processing speed, along with a self-report measure. Bivariate analyses were conducted to examine the relationship between cognitive functioning and each physical therapy outcome (session attendance, attaining goals, and changes in functional outcome measures), followed by logistic regressions with age, education, gender, and disability level as covariates.

RESULTS

Difficulty learning new verbal information was associated with a greater likelihood of "no showing" one or more of their physical therapy sessions. Reductions in working memory and processing speed were associated with PwMS not meeting all their rehabilitation goals. Despite deficits in new learning, memory, and processing speed, 85.2% of those with pre-/postscores showed improvements in at least one functional outcome measure following physical therapy intervention.

DISCUSSION AND CONCLUSIONS

These findings demonstrate the ability for PwMS to make functional motor gains despite the presence of cognitive impairments and highlight the potential contributions of cognitive functioning on attendance and goal attainment of physical therapy intervention.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A362, which includes background, methods, results, and discussion in the authors' own voices).

Motor sequence learning in a goal-directed stepping task in persons with multiple sclerosis: a pilot study

Motor sequence learning in persons with multiple sclerosis (pwMS) and healthy controls (HC) under implicit or explicit learning conditions has not yet been investigated in a stepping task. Given the prevalent cognitive and mobility impairments in pwMS, this is important in order to understand motor learning processes and optimize rehabilitation strategies. Nineteen pwMS (the Expanded Disability Status Scale = 3.4 ± 1.2) and 18 HC performed a modified serial reaction time task by stepping as fast as possible on a stepping tile when it lit up, either with (explicit) or without (implicit) knowledge of the presence of a sequence beforehand. Motor sequence learning was studied by examining response time changes and differences between sequence and random blocks during the learning session (acquisition), 24 h later (retention), and in three dual-task (DT) conditions at baseline and retention (automaticity) using subtracting sevens, verbal fluency, and vigilance as concurrent cognitive DTs. Response times improved and were lower for the sequenced compared with the random blocks at the post- and retention tests (P's < 0.001). Response times during DT conditions improved after learning, but DT cost improved only for the subtracting sevens DT condition. No differences in learning were observed between learning conditions or groups. This study showed motor sequence learning, by acquisition and retention, in a stepping task in pwMS with motor impairments, to a similar degree as HC and regardless of learning conditions. Whether automaticity increased remains unclear.

Functional relevance of resistance training-induced neuroplasticity in health and disease

Repetitive, monotonic, and effortful voluntary muscle contractions performed for just a few weeks, i.e., resistance training, can substantially increase maximal voluntary force in the practiced task and can also increase gross motor performance. The increase in motor performance is often accompanied by neuroplastic adaptations in the central nervous system. While historical data assigned functional relevance to such adaptations induced by resistance training, this claim has not yet been systematically and critically examined in the context of motor performance across the lifespan in health and disease. A review of muscle activation, brain and peripheral nerve stimulation, and imaging data revealed that increases in motor performance and neuroplasticity tend to be uncoupled, making a mechanistic link between neuroplasticity and motor performance inconclusive. We recommend new approaches, including causal mediation analytical and hypothesis-driven models to substantiate the functional relevance of resistance training-induced neuroplasticity in the improvements of gross motor function across the lifespan in health and disease.

Procedural Learning Improves Cognition in Multiple Sclerosis

Background:

Multiple sclerosis (MS) is considered a neurodegenerative disease and an inflammatory demyelinating neuropathology in young population. Procedural memory has been poorly investigated in MS.

Objective:

We assessed whether the MS group was able to develop a motor-cognitive skill, using a procedural task (PLSC) developed in our laboratory, applying a manual and serial reaction time (RT) paradigm to semantic categorization.

Methods:

We evaluated 26 MS patients and 26 socio-demographic matched control participants using the PLSC task.

Results:

Using non-parametric statistical analyses, we observed a significant improvement of semantic categorization RTs with practice (p = 0.002), even with new verbal material to categorize in MS patients (p = 0.006), despite their motor and executive moderate deficits. This same profile of semantic procedural learning in MS was observed in previous studies carried out with Alzheimer’s and Parkinson’s diseases. Moreover, the visual-motor RTs remained stable or slightly improved over the five blocks in both groups, as well as in the AD groups of previous studies. The MS group showed longer visual-motor reaction times than those of the control group (p < 0.042), except in motor initiation aspect (p = 0.064). Both groups showed no significant differences for any type of error. Additionally, disability level and cognitive performances were not associated with the ratio of semantic procedural learning.

Conclusion:

The present results support the notion that MS patients may be capable of acquiring semantic skill, despite their motor disabilities and executive troubles. This work also addresses the possibilities to improve motor-cognitive skill RTs in neurodegenerative diseases.