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?

Abstract

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.

Systematic Review on Exercise Training as a Neuroplasticity-Inducing Behavior in Multiple Sclerosis

“…Of those abstracts, 10 met eligibility criteria and were subsequently fully reviewed for data extraction and synthesis. [18][19][20][21][22][23][24][25][26][27] Participant Characteristics, Interventions, Outcomes Table 1 summarizes the participant characteristics, study characteristics, and primary study results for each of the 10 papers reviewed. Briefly, a majority of the papers involved persons with mild ambulatory disability with relapsingremitting MS, and pilot/feasibility RCTs in relatively small samples of persons with MS (ranging from 2 to 35 persons with MS).…”

“…Of note, 2 of the 10 selected papers were secondary data analyses (ie, reporting on different neuroimaging outcomes from an original intervention) of a primary paper. 21,25 All 8 of the original papers included in the present systematic review involved different exercise prescriptions and all 10 papers (including secondary analyses) involved different neuroimaging outcomes.…”

“…There were 8 different exercise training interventions that were examined across the 10 papers. Those interventions involved various modalities of aerobic exercise training, [19][20][21][23][24][25][26] progressive resistance training (PRT), 22,23,27 and balance training. 18 Duration of exercise training ranged from 4 to 24 weeks in length.…”

“…18 Duration of exercise training ranged from 4 to 24 weeks in length. Across the 8 identified exercise training interventions, 1 intervention involved 4 weeks of exercise training, 23 1 involved 8 weeks of exercise training, 26 4 involved 12 weeks of exercise training, [18][19][20][21]24,25 1 involved 16 weeks of exercise training, 27 and 1 intervention involved 24 weeks of exercise training. 22 Regarding frequency, exercise training took place between 2 and 10 times per week across the 8 interventions.…”

“…22 Regarding frequency, exercise training took place between 2 and 10 times per week across the 8 interventions. One intervention took place 2 times per week, 22 4 took place 3 times per week, [19][20][21]24,25,27 1 took place 4 times per week, 26 1 took place 5 times per week, 18 and another intervention took place 10 times per week (ie, twice per day on 5 days per week). 23 Some studies reported exercise intensity and progression in great detail (eg, Sandroff et al 20 ), whereas others did not (eg, Leavitt et al 19 ).…”