Article

Aerobic exercise increases hippocampal volume and improves memory in multiple sclerosis: Preliminary findings

a Kessler Foundation Research Center , West Orange , NJ , USA.
Neurocase (Impact Factor: 1.12). 10/2013; 20(6). DOI: 10.1080/13554794.2013.841951
Source: PubMed

ABSTRACT

Multiple sclerosis leads to prominent hippocampal atrophy, which is linked to memory deficits. Indeed, 50% of multiple sclerosis patients suffer memory impairment, with negative consequences for quality of life. There are currently no effective memory treatments for multiple sclerosis either pharmacological or behavioral. Aerobic exercise improves memory and promotes hippocampal neurogenesis in nonhuman animals. Here, we investigate the benefits of aerobic exercise in memory-impaired multiple sclerosis patients. Pilot data were collected from two ambulatory, memory-impaired multiple sclerosis participants randomized to non-aerobic (stretching) and aerobic (stationary cycling) conditions. The following baseline/follow-up measurements were taken: high-resolution MRI (neuroanatomical volumes), fMRI (functional connectivity), and memory assessment. Intervention was 30-minute sessions 3 times per week for 3 months. Aerobic exercise resulted in 16.5% increase in hippocampal volume and 53.7% increase in memory, as well as increased hippocampal resting-state functional connectivity. Improvements were specific, with no comparable changes in overall cerebral gray matter (+2.4%), non-hippocampal deep gray matter structures (thalamus, caudate: -4.0%), or in non-memory cognitive functioning (executive functions, processing speed, working memory: changes ranged from -11% to +4%). Non-aerobic exercise resulted in relatively no change in hippocampal volume (2.8%) or memory (0.0%), and no changes in hippocampal functional connectivity. This is the first evidence for aerobic exercise to increase hippocampal volume and connectivity and improve memory in multiple sclerosis. Aerobic exercise represents a cost-effective, widely available, natural, and self-administered treatment with no adverse side effects that may be the first effective memory treatment for multiple sclerosis patients.

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Available from: Christopher M Cirnigliaro, May 04, 2015
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    • "Studies investigating physical activity effects on brain integrity have mainly been based on single brain markers (e.g., GM volume, functional brain response, functional/structural connectivity), and few used a multimodal imaging approach. However, in one study, it was shown that aerobic exercise not only increased hippocampal volume but also increased hippocampal resting state functional connectivity in patients with multiple sclerosis (Leavitt et al., 2014). Further, in another study (Burdette et al., 2010), it was found that exercise was associated with greater connectivity between the hippocampus and the anterior cingulate cortex, which was accompanied with higher hippocampal perfusion. "
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    • "This too might depend on the domain of cognition that is impaired. For example, perhaps acute aerobic exercise benefits memory, but not executive control, in memory-impaired persons with MS, analogous to the results of a recent case study involving exercise training effects on cognition in MS (Leavitt et al., 2014). "
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