White Matter Integrity Declined Over 6-Months, but Dance Intervention Improved Integrity of the Fornix of Older Adults

Abstract

Degeneration of cerebral white matter (WM), or structural disconnection, is one of the major neural mechanisms driving age-related decline in cognitive functions, such as processing speed. Past cross-sectional studies have demonstrated beneficial effects of greater cardiorespiratory fitness, physical activity, cognitive training, social engagement, and nutrition on cognitive functioning and brain health in aging. Here, we collected diffusion magnetic resonance (MRI) imaging data from 174 older (age 60–79) adults to study the effects of 6-months lifestyle interventions on WM integrity. Healthy but low-active participants were randomized into Dance, Walking, Walking + Nutrition, and Active Control (stretching and toning) intervention groups (NCT01472744 on ClinicalTrials.gov). Only in the fornix there was a time × intervention group interaction of change in WM integrity: integrity declined over 6 months in all groups but increased in the Dance group. Integrity in the fornix at baseline was associated with better processing speed, however, change in fornix integrity did not correlate with change in processing speed. Next, we observed a decline in WM integrity across the majority of brain regions in all participants, regardless of the intervention group. This suggests that the aging of the brain is detectable on the scale of 6-months, which highlights the urgency of finding effective interventions to slow down this process. Magnitude of WM decline increased with age and decline in prefrontal WM was of lesser magnitude in older adults spending less time sedentary and more engaging in moderate-to-vigorous physical activity. In addition, our findings support the anterior-to-posterior gradient of greater-to-lesser decline, but only in the in the corpus callosum. Together, our findings suggest that combining physical, cognitive, and social engagement (dance) may help maintain or improve WM health and more physically active lifestyle is associated with slower WM decline. This study emphasizes the importance of a physically active and socially engaging lifestyle among aging adults.

Long-term changes in time spent walking and subsequent cognitive and structural brain changes in older adults

“…Previous cross-sectional studies have shown that NAWM AD increases with advanced age (Hsu et al, 2010; Michielse et al, 2010) and can distinguish healthy older adults from those with mild cognitive impairment or dementia (Bosch et al, 2012). Longitudinal studies show that AD increases over relatively brief periods of time (i.e., <5 years) among older adults (Burzynska et al, 2017; Rieckmann et al, 2016; Sexton et al, 2014; Storsve et al, 2016), a finding that was confirmed in the current study. Previous studies that have examined the association between PA and WM integrity in older adults primarily have been cross-sectional and have suggested an inverse correlation between PA and WM diffusivity (Sexton et al, 2016).…”

Comparing the Transfer Effects of Simultaneously and Sequentially Combined Aerobic Exercise and Cognitive Training in Older Adults

“…Similarly, although aerobic fitness is positively associated with cognitive abilities Colcombe and Kramer 2003), baseline aerobic fitness has rarely been investigated as a potential moderator of training-related change (cf. Burzynska et al 2017;Voss et al 2013). This is also paralleled by finding that fit older adults show less cognitive decline than their sedentary counterparts and that physical exercise can improve cognitive functions Colcombe and Kramer 2003).…”

“…Future studies could examine the reverse order, which might yield different results given the evidence suggesting that aerobic exercises could boost subsequent cognitive performance (Chang et al 2012). Another future consideration would be to compare simultaneous multimodal training as done presently, against a more integrated multimodal intervention such as dance (Burzynska et al 2017), which has also shown positive effects on cognition and associated neuroanatomical changes in older adults.…”

Effects of a randomized exercise trial on physical activity, psychological distress and quality of life in older adults

“…The Strengthening/Stretching/Stability group served as the active control condition. In a primary outcomes paper it was demonstrated that white matter (WM) integrity declined in all four conditions with the exception of WM in the fornix region which increased in the dance condition [33]. However, these changes in WM integrity were not associated with changes in processing speed.…”

“…Specific details of the trial and participant flow through the study have been previously published [33,34]. Briefly, all groups met at local campus recreation centers for approximately one hour three times per week for 24 weeks, and each session began with a warm-up consisting of light walking followed by stretching exercises targeting major muscle groups.…”