A model of different cognitive processes during spontaneous and intentional coupling to music in multiple sclerosis

Evidence for using auditory-motor coupling in neurological rehabilitation to facilitate walking is increasing. However, the distinction between spontaneous and intended coupling and its underlying mechanisms is yet to be investigated. In this study, we include 30 persons with multiple sclerosis and 30 healthy controls (HCs) in an experiment with two sessions in which participants were asked to walk to music with various tempi, matching their preferred walking cadence (PWC) up to 10% above in incremental steps of 2%. In the first session, no instructions were given to synchronize. In the second, participants were instructed to synchronize steps to the beats. Spontaneous synchronization was possible at 0% and +2% of the PWC, and fewer persons with multiple sclerosis were able to do so compared with HCs. Instruction was needed to synchronize at above +2% tempo in all participants. In the instructed session, the +6% condition marked a cutoff for cognitively impaired persons, as they were no longer able to synchronize. Based on our findings, we constructed a model illustrating that spontaneous entrainment is limited, operating during spontaneous coupling at only 0% and +2% of the PWC, and that at a higher tempo, entrainment requires intentional synchronization, with an active cognitive control mechanism

Comparing 16 different dual-tasking paradigms in individuals with multiple sclerosis and healthy controls : working memory tasks indicate cognitive-motor interference

Background: Cognitive-motor interference (CMI) is measured by dual-tasking (DT), which involves motor and cognitive tasks. There is no consensus as to whether CMI is present in multiple sclerosis (MS). Objectives: We investigated the effects of 16 DT conditions by measuring motor complexity, cognitive domain, and task difficulty. Method: In total, 40 persons with MS (pwMSs) with Expanded Disease Status Scale (EDSS) 3.2 +/- 1.7 and 31 age- and sex-matched healthy controls (HCs) completed 2 single walking, 8 single cognitive, and 2 complex walking tasks and 16 cognitive-motor DT. The main outcomes were mean values of gait velocity and the percentage change from single to DT (motor DT costs, mDTCs) and mean values of cognitive task accuracy and the percentage changes (cognitive DTC, cDTC). Results: Two-way analyses of variance showed the main effect of cognitive task yielded anFratio ofF((4, 268))= 72.35,p< 0.01, for mean gait velocity, and anFratio ofF((4, 304))= 17.12,p< 0.001, for mDTC, indicating that the mean velocity was significantly lower and the mDTC significantly higher for DS_B (mean = 1.27, SD = 0.03, and mean = 13.52, SD = 1.28, respectively). The main effect of cognitive task yielded anFratio ofF((4, 116))= 84.32,p< 0.001, with the lowest average accuracy for DS_B (mean = 43.95, SD = 3.33); no effect was found for cDTC. In pwMSs, the EDSS accounted for 28% (F= 13.65,p= 0.001) of variance in a model predicting the highest mDTC. Conclusions: Overall, among different cognitive tasks added, the Digit Span backward was the most interfering cognitive task over gait velocity and accuracy. The effect was similar independently from the motor complexity and the group. PwMSs and HCs behaved in a similar manner at all motor complexity levels and during all cognitive task

A pilot study of the effects of running training on visuospatial memory in MS: A stronger functional embedding of the hippocampus in the default-mode network?

Background/objective: Endurance exercise can improve memory function in persons with multiple sclerosis (pwMS), but the effects on hippocampal functioning are currently unknown. We investigated the effects of a running intervention on memory and hippocampal functional connectivity in pwMS. Methods/results: Memory and resting-state functional magnetic resonance imaging (fMRI) data were collected in a running intervention (n = 15) and waitlist group (n = 14). Visuospatial memory improvement was correlated to increased connectivity between the hippocampus and the default-mode network (DMN) in the intervention group only. Conclusion: As a result of endurance exercise, improvements in visuospatial memory may be mediated by a stronger functional embedding of the hippocampus in the DMN

Cognitive rehabilitation and aerobic exercise for cognitive impairment in people with progressive multiple sclerosis (CogEx): a randomised, blinded, sham-controlled trial

Background Cognitive dysfunction in people with relapsing-remitting multiple sclerosis can improve with cognitive rehabilitation or exercise. Similar effects have not been clearly shown in people with progressive multiple sclerosis. We aimed to investigate the individual and synergistic effects of cognitive rehabilitation and exercise in patients with progressive multiple sclerosis.Methods CogEx was a randomised, sham-controlled trial completed in 11 hospital clinics, universities, and rehabilitation centres in Belgium, Canada, Denmark, Italy, UK, and USA. Patients with progressive multiple sclerosis were eligible for inclusion if they were aged 25-65 years and had an Expanded Disability Status Scale (EDSS) score of less than 7. All had impaired processing speed defined as a performance of 1 center dot 282 SD or greater below normative data on the Symbol Digit modalities Tests (SDMT). Participants were randomly assigned (1:1:1:1), using an interactive web-response system accessed online from each centre, to cognitive rehabilitation plus exercise, cognitive rehabilitation plus sham exercise, exercise plus sham cognitive rehabilitation, or sham exercise plus sham cognitive rehabilitation. The study statistician created the randomisation sequence that was stratified by centre. Participants, outcome assessors, and investigators were blinded to group allocation. The study statistician was masked to treatment during analysis only. Interventions were conducted two times per week for 12 weeks: cognitive rehabilitation used an individualised, computer-based, incremental approach to improve processing speed; sham cognitive rehabilitation consisted of internet training provided individually; the exercise intervention involved individualised aerobic training using a recumbent arm-leg stepper; and the sham exercise involved stretching and balance tasks without inducing cardiovascular strain. The primary outcome measure was processing speed measured by SDMT at 12 weeks; least squares mean differences were compared between groups using linear mixed model in all participants who had a 12-week assessment. The trial is registered with ClinicalTrials.gov, NCT03679468, and is completed.Findings Between Dec 14, 2018, and April 2, 2022, 311 people with progressive multiple sclerosis were enrolled and 284 (91%) completed the 12-week assessment (117/311 [38%] male and 194/311 [62%] female). The least squares mean group differences in SDMT at 12 weeks did not differ between groups (p=0 center dot 85). Compared with the sham cognitive rehabilitation and sham exercise group (n=67), differences were -1 center dot 30 (95% CI -3 center dot 75 to 1 center dot 16) for the cognitive rehabilitation plus exercise group (n=70); -2 center dot 78 (-5 center dot 23 to -0 center dot 33) for the sham cognitive rehabilitation plus exercise group (n=71); and -0 center dot 71 (-3 center dot 11 to 1 center dot 70) for the cognitive rehabilitation plus sham exercise group (n=76). 11 adverse events possibly related to the interventions occurred, six in the exercise plus sham cognitive rehabilitation group (pain, dizziness, and falls), two in the cognitive rehabilitation plus sham exercise group (headache and pain), two in the cognitive rehabilitation and exercise group (increased fatigue and pain), and one in the dual sham group (fall).Interpretation Combined cognitive rehabilitation plus exercise does not seem to improve processing speed in people with progressive multiple sclerosis. However, our sham interventions were not inactive.Studies comparing interventions with a non-intervention group are needed to investigate whether clinically meaningful improvements in processing speed might be attainable in people with progressive multiple sclerosis.Copyright (c) 2023 Elsevier Ltd. All rights reserved