Gray matter volume covariance networks associated with dual‐task cost during walking‐while‐talking

Abstract

We studied gray matter volume covariance networks associated with normal pace walking (NPW) speed and dual‐task costs (DTCs) during walking‐while‐talking (WWT)—a mobility stress test that involves walking while reciting alternate letters of the alphabet. Using a multivariate covariance‐based analytic approach, we identified gray matter networks associated with NPW speed (mean 102.1 cm/s ±22.5 cm/s) and DTC (percent difference in gait speed between NPW and WWT, mean 25.9% ± 18.8%) in 139 older adults without dementia (M = 75.3 ± 6.1 years). The gray matter network associated with NPW was primarily composed of supplementary motor area, precuneus cortex, and the middle frontal gyrus. Greater expression of this NPW network was associated with better processing speed (trail‐making test A [r = −0.30, p = 0.005]) and executive function (trail‐making test B − A [r = −0.43, p < 0.0001]). The gray matter network associated with DTC was primarily composed of medial prefrontal, cingulate, and thalamic regions. Greater expression of this DTC network was associated with better episodic memory performance on the free and cued selective reminding test (r = 0.30, p = 0.007). These results suggest that NPW speed and DTC are supported by different networks, and are associated with different cognitive domains.

Brain volumes and dual-task performance correlates among individuals with cognitive impairment: a retrospective analysis

“…Likewise, there is little known about the relationship between DT function and cognitive relevant brain areas. Previous studies have identified brain areas uniquely correlated with DT performance, including frontal, temporal, and cingulate regions (Doi et al 2017;Tripathi et al 2019). While not the hallmark of cognitive disorders, there is evidence of decreased volume, decrease neuronal integrity, and lower cerebral blood flow in motor-related brain areas such as the basal ganglia and primary motor cortex in those with MCI and dementia, and these findings have been shown to be associated with both single and dual task gait variability (Annweiler et al 2013;Jiji et al 2013;Nakamura et al 1997).…”

“…We hypothesized that motor relevant brain volumes would be more associated with motor dual-task effects (mDTE), indicating a decline in motor performance under DT conditions. Based on the literature, we hypothesized that the superior frontal lobe caudate, putamen, middle parietal and cerebellum would be associated with mDTE (Allali et al 2019;Poldrack et al 2005;Tripathi et al 2019). We also hypothesized that cognitive relevant brain volumes would be more associated with cognitive dual-task effects (cogDTE), indicating a decline in cognitive performance under DT conditions.…”

“…We also hypothesized that cognitive relevant brain volumes would be more associated with cognitive dual-task effects (cogDTE), indicating a decline in cognitive performance under DT conditions. Based on the literature, we hypothesized that the inferior frontal, hippocampus, and cingulate regions will be associated with cogDTE (Tripathi et al 2019). The second aim of this study was to determine if task prioritization (i.e., a choice to focus more attention on one of two competing and concurrent tasks, cognitive or motor) related to dual task effect (DTE) can provide information about brain volumes in individuals with cognitive impairment.…”

Neural Correlates of Stepping in Healthy Elderly: Parietal and Prefrontal Cortex Activation Reflects Cognitive-Motor Interference Effects

“…Another explanation for a much broader implicated network in DT was also discussed in Tripathi et al (2019) . The authors hypothesize that structural brain loss in regions involved in DT, might contribute to an impaired neural functioning during DT and consequently prompt a compensation by alternative pathways.…”

“…Previous studies showed that PFC atrophies more than other regions ( Dumurgier et al, 2012 ; Storsve et al, 2014 ; Doi et al, 2017 ) and is also often functionally underutilized with age ( Holtzer et al, 2011 ). Several studies showed an association of DT performance (i.e., processing speed and executive function) and the gray matter volume of various areas of motor control including PFC ( Allali et al, 2019 ; Blumen et al, 2019 ; Tripathi et al, 2019 ). Albeit structure-function evaluations of these regions are scarce, first evidence indicates the potential moderator role, which brain prefrontal activation can have on volume loss in elderly ( Wagshul et al, 2019 ).…”