Effects of walking exercise training on learning and memory and hippocampal neuroimaging outcomes in MS: A targeted, pilot randomized controlled trial

PURPOSE

The current pilot study involved a single-blind, randomized controlled trial (RCT) on the effects of treadmill walking exercise training compared with an active control condition on learning and memory (L/M) and hippocampal neuroimaging outcomes in 11 fully-ambulatory persons with multiple sclerosis (MS) who demonstrated impairments in new learning.

METHODS

The study protocol is registered at clinicaltrials.gov: NCT03319771 (February 2018). Eleven fully-ambulatory persons with MS-related impairments in new learning were randomly assigned into either 12-weeks of supervised, treadmill walking exercise training or 12-weeks of low-intensity resistive exercise (active control condition). Participants underwent neuropsychological tests of L/M and hippocampal neuroimaging before and after the 12-week study period; outcomes were administered by treatment-blinded assessors.

RESULTS

There were moderate-to-large intervention effects on measures of verbal L/M (η_p² = 0.11, d = 0.63, 95% CI: -0.61, 1.83), whereby those in the intervention condition demonstrated improvement in California Verbal Learning Test-II (CVLT-II) scores compared with the control condition. There were smaller effects on a composite L/M measure (η_p² = 0.02, d = 0.28, 95% CI: -0.93, 1.46). There were large intervention effects on normalized hippocampal volume (η_p² = 0.36, d = 1.13, 95% CI: 0.09, 2.82), whereby hippocampal volume was preserved in the intervention condition, compared with hippocampal atrophy in the control condition. By comparison, there were no intervention effects on hippocampal resting-state functional connectivity.

CONCLUSIONS

Collectively, this study provides initial proof-of-concept data for further examining treadmill walking exercise training as a possible behavioral approach for managing L/M impairment and preserving hippocampal volume as common and debilitating manifestations of MS.

Cognitive fatigue in traumatic brain injury: a pilot study comparing state and trait fatigue

OBJECTIVE

Cognitive fatigue is a common and disabling symptom following a traumatic brain injury (TBI). Literature on cognitive fatigue has distinguished between two types of fatigue: "state" fatigue refers to the acute experience of fatigue, whereas "trait" fatigue refers to the susceptibility to fatigue over an extended period. However, it is not clear whether state and trait fatigue are distinguishable constructs. Here, we examine the relationship between state and trait fatigue in individuals with TBI, hypothesizing that trait and state measures assess different constructs.

PARTICIPANTS

Twenty-one participants with moderate-severe TBI were recruited.

DESIGN

Participants underwent a cognitively fatiguing task while in an MRI scanner and completed self-report measures examining trait and state fatigue.

RESULTS

No correlation was found between state and trait fatigue. However, the two measures of trait fatigue, Fatigue Severity Scale (FSS) and the Modified Fatigue Impact Scale (MFIS), correlated with one another; additionally only trait fatigue correlated with depression scores, consistent with the literature.

CONCLUSION

These findings suggest that trait and state fatigue may not be interdependent and that it is important to carefully define the type of fatigue under consideration when assessing fatigue in individuals with TBI.

Internet-based technology in multiple sclerosis: Exploring perceived use and skills and actual performance

OBJECTIVE

The use of Internet-based technology (IBT) is an important component of everyday living. However, persons with multiple sclerosis (MS) may face barriers to use. This study aimed to compare IBT perceived use and skills and actual performance in persons with MS and healthy controls (HCs). In addition, it aimed to examine IBT perceptions as a unique predictor of IBT performance beyond demographic, cognitive, motor, and affective factors in persons with MS.

METHOD

Ninety-six persons with MS and 65 HCs aged 18 to 65 completed self-report and performance-based IBT measures along with assessments of cognition, motor function, and affect at a single time point.

RESULTS

The MS group reported perceptions of less IBT use and poorer skills than HCs and demonstrated worse IBT performance as per accuracy and speed on the Actual Reality. In persons with MS, IBT perceptions and performance were significantly associated. Cognition and dexterity were significantly associated with IBT performance, and anxiety was associated with IBT perceptions. Disease duration, processing speed, and IBT perceptions were unique predictors of IBT performance in the MS group within a multivariate model.

CONCLUSION

Persons with MS present with poorer IBT performance compared with HCs, which can limit participation. Processing speed and patient perceptions of IBT use and skills should be considered in technology design and training to improve the capabilities of persons with MS to use IBT for everyday living. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

A pilot randomized controlled trial of robotic exoskeleton-assisted exercise rehabilitation in multiple sclerosis

BACKGROUND

Co-occurring mobility and cognitive impairments are common, debilitating, and poorly-managed with pharmacological therapies in persons with multiple sclerosis (MS). Exercise rehabilitation (ER), particularly walking ER, has been suggested as one of the best approaches for managing these manifestations of MS. However, there is a focal lack of efficacy of ER on mobility and cognitive outcomes in persons with MS who present with substantial neurological disability. Such severe neurological disability oftentimes precludes the ability for participation in highly-intensive and repetitive ER that is necessary for eliciting adaptations in mobility and cognition. To address such a concern, robotic exoskeleton-assisted ER (REAER) might represent a promising intervention approach for managing co-occurring mobility and cognitive impairments in those with substantial MS disability who might not benefit from traditional ER.

METHODS

The current pilot single-blind, randomized controlled trial (RCT) compared the effects of 4-weeks of REAER with 4-weeks of conventional gait training (CGT) as a standard-of-care control condition on functional mobility (timed up-and-go; TUG), walking endurance (six-minute walk test; 6MWT), cognitive processing speed (CPS; Symbol Digit Modalities Test; SDMT), and brain connectivity (thalamocortical resting-state functional connectivity (RSFC) based on fMRI) outcomes in 10 persons with substantial MS-related neurological disability.

RESULTS

Overall, compared with CGT, 4-weeks of REAER was associated with large improvements in functional mobility (η_p²=.38), CPS (η_p²=.53), and RSFC between the thalamus and ventromedial prefrontal cortex (η_p²=.72), but not walking endurance (η_p²=.01). Further, changes in RSFC were moderately associated with changes in TUG, 6MWT, and SDMT performance, respectively, whereby increased thalamocortical RSFC was associated with improved functional mobility, walking endurance, and CPS (|ρ|>.36).

CONCLUSION

The current pilot RCT provides initial support for REAER as an approach for improving functional mobility and CPS, perhaps based on adaptive and integrative central nervous system plasticity, namely increases in RSFC between the thalamus and ventromedial prefrontal cortex, in a small sample of persons with substantial MS disability. Such a pilot trial provides proof-of-concept data for the design and implementation of an appropriately-powered RCT of REAER in a larger sample of persons with MS who present with co-occurring impairments in both mobility and cognitive functioning.

Prioritizing progressive MS rehabilitation research: A call from the International Progressive MS Alliance

Background:

People with multiple sclerosis (MS) experience myriad symptoms that negatively affect their quality of life. Despite significant progress in rehabilitation strategies for people living with relapsing-remitting MS (RRMS), the development of similar strategies for people with progressive MS has received little attention.

Objective:

To highlight key symptoms of importance to people with progressive MS and stimulate the design and implementation of high-quality studies focused on symptom management and rehabilitation.

Methods:

A group of international research experts, representatives from industry, and people affected by progressive MS was convened by the International Progressive MS Alliance to devise research priorities for addressing symptoms in progressive MS.

Results:

Based on information from the MS community, we outline a rationale for highlighting four symptoms of particular interest: fatigue, mobility and upper extremity impairment, pain, and cognitive impairment. Factors such as depression, resilience, comorbidities, and psychosocial support are described, as they affect treatment efficacy.

Conclusions:

This coordinated call to action—to the research community to prioritize investigation of effective symptom management strategies, and to funders to support them—is an important step in addressing gaps in rehabilitation research for people affected by progressive MS.

Using Signal Detection Theory to Better Understand Cognitive Fatigue

When we are fatigued, we feel that our performance is worse than when we are fresh. Yet, for over 100 years, researchers have been unable to identify an objective, behavioral measure that covaries with the subjective experience of fatigue. Previous work suggests that the metrics of signal detection theory (SDT)-response bias (criterion) and perceptual certainty (d')-may change as a function of fatigue, but no work has yet been done to examine whether these metrics covary with fatigue. Here, we investigated cognitive fatigue using SDT. We induced fatigue through repetitive performance of the n-back working memory task, while functional magnetic resonance imaging (fMRI) data was acquired. We also assessed cognitive fatigue at intervals throughout. This enabled us to assess not only whether criterion and d' covary with cognitive fatigue but also whether similar patterns of brain activation underlie cognitive fatigue and SDT measures. Our results show that both criterion and d' were correlated with changes in cognitive fatigue: as fatigue increased, subjects became more conservative in their response bias and their perceptual certainty declined. Furthermore, activation in the striatum of the basal ganglia was also related to cognitive fatigue, criterion, and d'. These results suggest that SDT measures represent an objective measure of cognitive fatigue. Additionally, the overlap and difference in the fMRI results between cognitive fatigue and SDT measures indicate that these measures are related while also separate. In sum, we show the relevance of SDT measures in the understanding of fatigue, thus providing researchers with a new set of tools with which to better understand the nature and consequences of cognitive fatigue.

Using functional connectivity changes associated with cognitive fatigue to delineate a fatigue network

Cognitive fatigue, or fatigue related to mental work, is a common experience. A growing body of work using functional neuroimaging has identified several regions that appear to be related to cognitive fatigue and that potentially comprise a "fatigue network". These include the striatum of the basal ganglia, the dorsolateral prefrontal cortex (DLPFC), the dorsal anterior cingulate cortex (dACC), the ventro-medial prefrontal cortex (vmPFC) and the anterior insula. However, no work has been conducted to assess whether the connectivity between these regions changes as a function of cognitive fatigue. We used a task-based functional neuroimaging paradigm to induce fatigue in 39 healthy individuals, regressed the signal associated with the task out of the data, and investigated how the functional connectivity between these regions changed as cognitive fatigue increased. We observed functional connectivity between these regions and other frontal regions largely decreased as cognitive fatigue increased while connectivity between these seeds and more posterior regions increased. Furthermore the striatum, the DLPFC, the insula and the vmPFC appeared to be central 'nodes' or hubs of the fatigue network. These findings represent the first demonstration that the functional connectivity between these areas changes as a function of cognitive fatigue.

Effect of Ozanimod on Symbol Digit Modalities Test Performance in Relapsing MS

BACKGROUND

Cognitive dysfunction, including slowed cognitive processing speed (CPS), is one of the most disabling symptoms of multiple sclerosis (MS). The Symbol Digit Modalities Test (SDMT) is a preferred measure of CPS for MS trials and routine screening. Based on encouraging SDMT results in the phase 3 SUNBEAM trial, these post hoc, exploratory analyses were conducted to further compare effects of the sphingosine 1-phosphate receptor modulator ozanimod versus intramuscular interferon β-1a on CPS in participants with relapsing multiple sclerosis (RMS).

METHODS

In the phase 3, double-blind, double-dummy, SUNBEAM study, adults (aged 18‒55 years) with RMS (N=1,346) were randomized to once-daily oral ozanimod 0.92 or 0.46 mg, or weekly intramuscular interferon β-1a 30 µg. The study continued until the last participant was treated for 12 months. CPS was measured as part of a secondary endpoint using the SDMT. Exploratory, post hoc analyses evaluated SDMT change and percentages of participants with clinically meaningful (≥4-point) SDMT improvement or worsening at months 6 and 12, and relationship between SDMT and brain volume on magnetic resonance imaging.

RESULTS

Ozanimod improved SDMT scores compared with interferon β-1a at months 6 and 12. At month 12, least squares mean difference in SDMT z-scores for ozanimod 0.92 mg versus interferon β-1a was 0.102 (95% CI, 0.031‒0.174, nominal p = 0.0051; standardized mean difference = 0.1376). A greater percentage of ozanimod 0.92 mg‒treated participants had clinically meaningful improvements in SDMT scores versus interferon β-1a at month 6 (30.0% versus 22.2%) and month 12 (35.6% versus 27.9%). Of those with SDMT improvement at month 6, 66.4% of those treated with ozanimod 0.92 mg and 55.9% of those treated with interferon β-1a had sustained improvement at month 12. Brain volume loss was similar for those with SDMT improvement versus worsening at month 12.

CONCLUSIONS

In these exploratory analyses, ozanimod had modestly beneficial effects on CPS in RMS participants. The effects of ozanimod on SDMT are being further evaluated in an ongoing 3-year clinical trial. SUNBEAM is registered on clinicaltrials.gov (NCT02294058) and the European Clinical Trials Database (EudraCT 2014-002320-27).

Smell as a clinical-marker for functional limitations in multiple sclerosis: A pilot study

BACKGROUND

Olfactory dysfunction is a common symptom of multiple sclerosis (MS). The questions of whether and to what degree olfactory dysfunction can serve as a clinical marker of MS disability (i.e. cognitive impairments and functional limitations) are not yet answered. The current study aimed to explore associations between olfactory function (i.e. smell identification) with cognitive capacities, functional performance and quality of life (QOL) in persons with MS.

METHODS

Olfactory function was measured by the University of Pennsylvania Smell Identification Test (UPSIT). Functional ability was assessed by the Actual Reality^TM (AR) task. QOL was assessed by the Multiple Sclerosis Quality of Life-54 (MSQOL-54). Cognition was assessed by the Brief International Cognitive Assessment for MS (BICAMS) in 23 MS patients and 15 matched healthy controls.

RESULTS

MS patients had lower UPSIT scores than healthy controls. Worse UPSIT scores were associated with reduced performances on the BICAMS and AR task as well as lower MSQOL-54 scores. Specifically, UPSIT scores were related to MSQOL-54 scores independent of BICAMS composite scores, while the relationship between UPSIT score and AR performance was mediated by BICAMS composite score.

CONCLUSION

This study confirms previous studies which concluded that olfactory function is impaired in MS. Furthermore, olfactory dysfunction is related to limitations in activity performance and QOL. Taken together with previous studies, olfactory function may be considered as a clinical marker related to MS disability. Longitudinal studies are needed to confirm these results.

Cognitive impairment in multiple sclerosis: clinical management, MRI, and therapeutic avenues

Multiple sclerosis is a chronic, demyelinating disease of the CNS. Cognitive impairment is a sometimes neglected, yet common, sign and symptom with a profound effect on instrumental activities of daily living. The prevalence of cognitive impairment in multiple sclerosis varies across the lifespan and might be difficult to distinguish from other causes in older age. MRI studies show that widespread changes to brain networks contribute to cognitive dysfunction, and grey matter atrophy is an early sign of potential future cognitive decline. Neuropsychological research suggests that cognitive processing speed and episodic memory are the most frequently affected cognitive domains. Narrowing evaluation to these core areas permits brief, routine assessment in the clinical setting. Owing to its brevity, reliability, and sensitivity, the Symbol Digit Modalities Test, or its computer-based analogues, can be used to monitor episodes of acute disease activity. The Symbol Digit Modalities Test can also be used in clinical trials, and data increasingly show that cognitive processing speed and memory are amenable to cognitive training interventions.

Effects of a Single Bout of Aquatic Exercise on Mood in Multiple Sclerosis: A Pilot Study

Background

Physical activity is known to be an effective way of managing multiple sclerosis (MS)-related symptoms. Furthermore, it has been reported that even a single bout of physical activity can yield improvements in mood in persons with MS. Aquatic exercise can be an effective and enjoyable physical activity in persons with MS. However, there is little research on the immediate effects of aquatic exercise on mood in people with MS. Thus, we assessed the acute effects of a single bout of aquatic exercise on mood.

Methods

Eight adults with MS participated in a 45-minute aquatic exercise class as well as 45 minutes of a seated rest control condition. The Profile of Mood States questionnaire was given before and after each condition (rest and aquatic exercise). Repeated-measures analysis of variance and paired-samples t tests were used to examine whether aquatic exercise resulted in improvement in mood. Due to the small sample size, effect sizes were considered.

Results

Moderate-to-large effect sizes indicated a condition × time interaction such that mood increased and fatigue decreased after a single bout of aquatic exercise compared with after rest.

Conclusions

This proof-of-concept study suggests that mood symptoms are improved immediately after a short bout of aquatic exercise. Future research is needed to explore whether these effects are reliable and whether they can be sustained with more frequent bouts of aquatic exercise.

Inpatient length of stay moderates the relationship between payer source and functional outcomes in pediatric brain injury

OBJECTIVE

To examine the extent to which race/ethnicity, length of rehabilitation hospital stay (LOS), and payer source contribute to functional status following inpatient rehabilitation in children with acquired brain injury (ABI).

DESIGN

Retrospective cohort study from a pediatric rehabilitation hospital including 485 individuals with ABI.

METHODS

Functional Independence Measure for Children (WeeFIM) scores were transformed into age-corrected Developmental Functional Quotients (DFQ) to examine the effects of race/ethnicity, LOS, and payer source (public insurance vs. private) on functional outcomes while controlling for year of admission, admission DFQ, time to rehabilitation, age, and brain injury aetiology.

RESULTS

Discharge DFQ scores tended to be lower for children with public insurance as well as those with longer LOS. There was no main effect of race/ethnicity, but a significant interaction effect for payer source×LOS (p < .001) was found. Further breakdown of the interaction showed lower discharge DFQ scores for children with public insurance primarily when LOS exceeded 28 days (p = .001).

CONCLUSION

Children with ABI who have both public insurance and LOS beyond 4 weeks tend to have poorer functional outcomes after inpatient rehabilitation. Because all children were receiving services at the same facility, payer source may be functioning as a proxy for other sociodemographic factors.

The emotional impact of the COVID-19 pandemic on individuals with progressive multiple sclerosis

Objective

Individuals with pre-existing chronic illness have shown increased anxiety and depression due to COVID-19. Here, we examine the impact of the COVID-19 pandemic on emotional symptomatology and quality of life in individuals with Progressive Multiple Sclerosis (PMS).

Methods

Data were obtained during a randomized clinical trial on rehabilitation taking place at 11 centers in North America and Europe. Participants included 131 individuals with PMS. Study procedures were interrupted in accordance with governmental restrictions as COVID-19 spread. During study closure, a COVID Impact Survey was administered via telephone or email to all participants, along with measures of depressive symptoms, anxiety symptoms, quality of life, and MS symptomatology that were previously administered pre-pandemic.

Results

4% of respondents reported COVID-19 infection. No significant changes were noted in anxiety, quality of life, or the impact of MS symptomatology on daily life from baseline to lockdown. While total HADS-depression scores increased significantly at follow-up, this did not translate into more participants scoring above the HADS threshold for clinically significant depression. No significant relationships were noted between disease duration, processing speed ability or EDSS, and changes in symptoms of depression or anxiety. Most participants reported the impact of the virus on their psychological well-being, with a little impact on financial well-being. The perceived impact of the pandemic on physical and psychological well-being was correlated with the impact of MS symptomatology on daily life, as well as changes in depression.

Conclusions

Overall, little change was noted in symptoms of depression or anxiety or overall quality of life.

Changes in plant function and root mycobiome caused by flood and drought in a riparian tree

Under increasingly harsh climatic conditions, conservation of threatened species requires integrative studies to understand stress tolerance. Riparian Ulmus minor Mill. populations have been massively reduced by Dutch Elm disease (DED). However, resistant genotypes were selected to restore lost populations. To understand the acclimation mechanisms to the succession of abiotic stresses, ramets of five DED-tolerant U. minor genotypes were subjected to flood and subsequently to drought. Physiological and biochemical responses were evaluated together with shifts in root-fungal assemblages. During both stresses, plants exhibited a decline in leaf net photosynthesis and an increase in percentage loss of stem hydraulic conductivity and in leaf and root proline content. Stomatal closure was produced by chemical signals during flood and hydraulic signals during drought. Despite broad similarities in plant response to both stresses, root-mycobiome shifts were markedly different. The five genotypes were similarly tolerant to moderate drought, however, flood tolerance varied between genotypes. In general, flood did not enhance drought susceptibility due to fast flood recovery, nevertheless, different responses to drought after flood were observed between genotypes. Associations were found between some fungal taxonomic groups and plant functional traits varying with flood and drought (e.g. proline, chlorophyll and starch content) indicating that the thriving of certain taxa depends on host responses to abiotic stress.

Beyond cognitive dysfunction: Relevance of ecological validity of neuropsychological tests in multiple sclerosis

In neurological diseases such as multiple sclerosis (MS), a neuropsychological assessment is often requested to assist clinicians in evaluating the role of cognition in a patient's level of everyday functioning. To be effective in this charge, it is assumed that performance on neuropsychological tests is related to how a person may function in everyday life, and the question is often asked: "Are neuropsychological tests ecologically valid?" In this review, we synthesize the literature that examines the use of neuropsychological tests to assess functioning across a variety of everyday functioning domains in MS (i.e. driving, employment, instrumental activities of daily living (IADLs)). However, we critically examine the usefulness of asking this broad question regarding ecological validity, given the psychometric and conceptual pitfalls it may yield. While many neuropsychological tests may be generally considered "ecologically valid" in MS, it is much more helpful to specify for whom, under what circumstances, and to what degree.

Feasibility of a school-based mindfulness program for improving inhibitory skills in children with autism spectrum disorder

BACKGROUND

Executive dysfunction is prevalent in children with autism spectrum disorder (ASD), including prominent difficulties in the two facets of inhibition, as well as with selective attention. School-based mindfulness has been used in typically-developing children to improve executive functioning, though this has not been investigated in children with ASD. Therefore, the purpose of this study was to examine the efficacy of a school-based mindfulness program for improving inhibition (prepotent response inhibition and interference control) and selective attention in children with ASD.

METHOD

Using a quasi-experimental, pre-post design, an eight week school-based mindfulness program (Mindful Schools;https://www.mindfulschools.org/), was administered to students with ASD (n = 27) at a private, not-for-profit school for children with special needs. The Walk/Don't Walk test and the Color-Word Interference test were used to evaluate prepotent response inhibition and interference control, respectively. Selective attention was measured using a cancellation test.

RESULTS

Significant improvements followed the intervention for prepotent response inhibition and interference control (medium effect sizes), as well as for overall selective attention (large effect size).

CONCLUSIONS

The study's findings demonstrate that school-based mindfulness holds promise for increasing specific executive functioning abilities in children with ASD.

0985 Utility Of A Rest-activity Ratio In A Pediatric Brain Injury Rehabilitation Sample: A Pilot Study

Introduction

Sleep is an important element of health that can impact daytime performance in brain injury rehabilitation. Actigraphy in a pediatric inpatient setting can pose challenges when there are increased amounts of time spent in a hospital bed. A rest-activity ratio (Duclos et al., 2013) has demonstrated utility in adult brain injury populations, showing sensitivity to improved regulation of the sleep-wake cycle as individuals recover during their hospitalization. The present study sought to examine the utility of this ratio in differentiating children with and without acquired brain injury (ABI).

Methods

Sixteen individuals, ages 8-16 (M=12.6, SD=2.4) admitted to an inpatient pediatric rehabilitation hospital wore an actigraph over a 7-day period. Eight inpatients were being treated for ABI whereas another 8 inpatients treated for other, non-neurological conditions served as a control. Raw activity counts across the 24-hour period were analyzed to derive a rest-activity ratio.

Results

Those with ABI had lower average ratios (0.73) compared with patients without ABI (0.84), F(1,14)=4.3, p=0.058. Individuals with ratios of 0.85 or higher were rated by their physical therapists as being more alert during therapy using a 5-point Likert scale, F(1,14)=4.1, p=0.061. While these results were marginally significant, this pilot sample was small, and the effect sizes were large (eta squared = 0.234 and 0.229 respectively).

Conclusion

The rest-activity ratio successfully distinguished those with ABI from a non-ABI sample. This preliminary evidence in a pediatric sample suggests that this ratio, shown to be sensitive to the effects of brain injury on sleep-wake regulation, may be a useful metric in the inpatient pediatric rehabilitation setting when sleep diaries may be difficult to obtain and patients may be spending more time in bed while awake. Future studies with larger sample sizes are needed to explore the correlates of this ratio with other aspects of rehabilitation after pediatric brain injury.

Support

This study was funded in part through a generous grant from the Church & Dwight Employee Giving Fund

Study protocol: improving cognition in people with progressive multiple sclerosis: a multi-arm, randomized, blinded, sham-controlled trial of cognitive rehabilitation and aerobic exercise (COGEx)

BACKGROUND

Cognitive dysfunction affects up to 70% of people with progressive MS (PMS). It can exert a deleterious effect on activities of daily living, employment and relationships. Preliminary evidence suggests that performance can improve with cognitive rehabilitation (CR) and aerobic exercise (EX), but existing data are predominantly from people with relapsing-remitting MS without cognitive impairment. There is therefore a need to investigate whether this is also the case in people with progressive forms of the disease who have objectively identified cognitive impairment. It is hypothesized that CR and EX are effective treatments for people with PMS who have cognitive impairment, in particular processing speed (PS) deficits, and that a combination of these two treatments is more effective than each individual treatment given alone. We further hypothesize that improvements in PS will be associated with modifications of functional and/or structural plasticity within specific brain networks/regions involved in PS measured with advanced MRI techniques.

METHODS

This study is a multisite, randomized, double-blinded, sham controlled clinical trial of CR and aerobic exercise. Three hundred and sixty subjects from 11 sites will be randomly assigned into one of four groups: CR plus aerobic exercise; CR plus sham exercise; CR sham plus aerobic exercise and CR sham plus sham exercise. Subjects will participate in the assigned treatments for 12 weeks, twice a week. All subjects will have a cognitive and physical assessment at baseline, 12 weeks and 24 weeks. In an embedded sub-study, approximately 30% of subjects will undergo structural and functional MRI to investigate the neural mechanisms underlying the behavioral response. The primary outcome is the Symbol Digit Modalities Test (SDMT) measuring PS. Secondary outcome measures include: indices of verbal and non-verbal memory, depression, walking speed and a dual cognitive-motor task and MRI.

DISCUSSION

The study is being undertaken in 6 countries (11 centres) in multiple languages (English, Italian, Danish, Dutch); with testing material validated and standardized in these languages. The rationale for this approach is to obtain a robustly powered sample size and to demonstrate that these two interventions can be given effectively in multiple countries and in different languages.

TRIAL REGISTRATION

The trial was registered on September 20th 2018 at www.clinicaltrials.gov having identifier NCT03679468. Registration was performed before recruitment was initiated.

Difference in Cortical Modulation of Walking between Persons with Multiple Sclerosis and Healthy Controls: An EEG pilot study

The overall goal of this study is to investigate the role of parietal cortex in the control of walking in persons with Multiple Sclerosis (pwMS). We examined within-brain connectivity and cortico-muscular connectivity as pwMS and healthy control (HC) participants walked on an instrumented treadmill. Cortical activity was collected using EEG, muscle activity was collected using wireless EMG modules, and gait data were obtained by using the instrumented treadmill. Results show significant activation of sensorimotor and posterior parietal cortex during walking in both groups. Connectivity between parietal (posterior cingulate cortex PCC) and premotor regions (pars opercularis), and between PCC and contralateral muscles were higher in the healthy control group. Higher connectivity correlated with higher walking speed.

Mobility and Cognitive Improvements Resulted from Overground Robotic Exoskeleton Gait-Training in Persons with MS

Multiple sclerosis (MS) is a non-traumatic, immune-mediated neurodegenerative disease of the central nervous system (CNS), affecting more than 2 million individuals globally and approximately one million in the United States [1], [2]. This autoimmune inflammatory disease of the CNS featuring both neuroinflammatory and neurodegenerative aspects [3], often results in mobility and cognitive impairment. Rehabilitation has been suggested as the best [4], and perhaps, one of few methods for restoring function in MS [5]. The goal of the present investigation is to examine the effects of 4 weeks of supervised, over-ground gait training using a robotic exoskeleton (RE) compared with a control condition (conventional gait therapy, CGT) in persons with MS with ambulatory and cognition disabilities. Four subjects (mean age=50 years, three females) with relapsing-remitting MS (RRMS) participated in this study and completed a total of eight sessions (1-hour/session) gait training in a standard therapy gym either using a RE supervised by an RE training physical therapist (PT) or with the CGT supervised by a PT. Outcome measures (walking speed and temporal-spatial parameters) were measured on a level surface without RE using an instrumented walkway, for both groups, pre- and post-intervention. The two participants in the RE group were also tested in the same testing environment, while wearing a RE pre- and post-intervention. Cognitive processing speed was assessed using the Symbol Digit Modalities Test (SDMT) pre- and post-intervention. Subjects in the RE group tested without a RE increased average walking speed, stride length, and step length with decreased stride width and step time bilaterally after the 8-session of RE training. The two participants in the CGT group only had modest improvements in walking performance. Furthermore, while the CGT group had no improvements in the processing speed (SDMT scores), an average of 80% improvement in the processing speed was noted in the RE group.

Protocol for a systematically-developed, phase I/II, single-blind randomized controlled trial of treadmill walking exercise training effects on cognition and brain function in persons with multiple sclerosis

Slowed cognitive processing speed (CPS) is a common and debilitating consequence of multiple sclerosis (MS) that is notoriously difficult to treat. As such, we undertook a systematic line of research that indicated that supervised, progressive treadmill walking exercise (TMWX) training might improve CPS and brain functioning among fully-ambulatory persons with MS. The current study will be the first adequately-powered, single-blind randomized controlled trial (RCT) that examines the efficacy of 12-weeks of TMWX training compared with an active control condition on CPS, thalamocortical brain connectivity (based on resting-state fMRI), and exploratory functional outcomes in 88 fully-ambulatory persons with MS who present with slowed CPS. The intervention condition involves supervised, progressive TMWX training 3 times/week over 12-weeks; this initially involves 15-min of light-to-moderate intensity TMWX that progresses up to 40-min of vigorous intensity TMWX. The active control condition involves supervised, minimal intensity, stretching-and-resistance exercise that will be delivered on the same frequency as the intervention condition. The primary study outcomes involve Symbol Digit Modalities Test performance (i.e., CPS) and fMRI-based measures of thalamocortical resting-state functional connectivity. Exploratory study outcomes involve measures of community participation, activities of daily living, quality of life, and functional mobility. All study outcomes will be administered before and after the 12-week study period by treatment-blinded assessors. If successful, the current study will provide the first Class I evidence for the effects of TMWX training as an approach for improving CPS and its neural correlate, and possibly mitigating the impact of slowed CPS on functional outcomes in MS.

The application of Strategy-based Training to Enhance Memory (STEM) in multiple sclerosis: A pilot RCT

New learning and memory (NLM) impairments are common in multiple sclerosis (MS), negatively impacting daily life. Few studies seek to remediate these deficits to improve everyday functioning. Self-generation, spaced learning and retrieval practice have been shown to improve NLM in healthy persons and have been incorporated into an 8-session treatment protocol, Strategy-based Training to Enhance Memory (STEM). STEM teaches participants about each of the techniques, how to apply them in daily life and provides practice. Participants are taught to restructure a memory-demanding situation to optimize self-generation, spaced learning and retrieval practice. This pilot double-blind, placebo-controlled, randomized clinical trial (RCT) tested the efficacy of STEM in 20 learning-impaired participants with clinically definite MS (9 treatment, 11 control). Significant treatment effects were noted on self-report measures of daily functioning (primary outcome). Objective neuropsychological testing approached significance, showing a medium-large effect on verbal NLM. Results suggest that STEM may improve everyday functioning in individuals with MS. A full-scale RCT is warranted to validate findings in a larger sample so that findings may be generalized to the broader MS community.

Comparing learning performance on the open trial selective reminding test with the California verbal learning test II in traumatic brain injury

Introduction: Learning and memory deficits are prevalent following moderate to severe traumatic brain injury (TBI), affecting between 54% and 84% of impacted individuals.Objective: The current study examined learning performance on two tests of verbal memory: the OT-SRT and the CVLT-II.Methods: Sixty-eight participants with TBI performed the OT-SRT and the CVLT-II on two different days. Additionally, all participants completed cognitive tests assessing processing speed, working memory and executive functions. By definition, all participants with TBI were identified as having impaired learning on the OT-SRT, however only 38 were also identified as impaired on the CVLT-II. The sample was thus divided into two groups, those who failed both tests (Fail-2) and those who failed only the OT-SRT (Fail-1).Results: The Failed-1 group showed significantly better performance in processing speed, working memory and executive functions compared to the Fail-2 group. On the CVLT-II, the Fail-1 group performed significantly better on the number of words recalled on trials 1 and 5 compared to the Fail-2 group. Both groups performed similarly the OT-SRT.Discussion: The CVLT-II and the OT-SRT are not equivalent tests and should not be used interchangeably.

Computerized neuropsychological assessment devices in multiple sclerosis: A systematic review

Background:

The proliferation of computerized neuropsychological assessment devices (CNADs) for screening and monitoring cognitive impairment is increasing exponentially. Previous reviews of computerized tests for multiple sclerosis (MS) were primarily qualitative and did not rigorously compare CNADs on psychometric properties.

Objective:

We aimed to systematically review the literature on the use of CNADs in MS and identify test batteries and single tests with good evidence for reliability and validity.

Method:

A search of four major online databases was conducted for publications related to computerized testing and MS. Test–retest reliability and validity coefficients and effect sizes were recorded for each CNAD test, along with administration characteristics.

Results:

We identified 11 batteries and 33 individual tests from 120 peer-reviewed articles meeting the inclusion criteria. CNADs with the strongest psychometric support include the CogState Brief Battery, Cognitive Drug Research Battery, NeuroTrax, CNS-Vital Signs, and computer-based administrations of the Symbol Digit Modalities Test.

Conclusion:

We identified several CNADs that are valid to screen for MS-related cognitive impairment, or to supplement full, conventional neuropsychological assessment. The necessity of testing with a technician, and in a controlled clinic/laboratory environment, remains uncertain.