The Physiologic Complexity of Prefrontal Oxygenation Dynamics Is Associated With Age and Executive Function: An Exploratory Study.

Background: The hemodynamics of prefrontal cortex (PFC) oxygenation are regulated by numerous processes operating over multiple temporal scales, producing complex patterns in its output fluctuations. Age may alter this multiscale regulation of PFC oxygenation, leading to diminished physiologic complexity of this important regulatory process. We aimed to characterize the effects of age on such complexity and its relationship to performance of an executive n-back task.

The effects of cognitive impairment on the multi-scale dynamics of standing postural control during visual-search in older men.

Background: Cognitive impairment disrupts postural control, particularly when standing while performing an unrelated cognitive task (i.e., dual-tasking).

Transcranial Direct Current Stimulation May Reduce Prefrontal Recruitment During Dual Task Walking in Functionally Limited Older Adults - A Pilot Study.

Introduction: Transcranial direct current stimulation (tDCS) targeting the left dorsolateral prefrontal cortex (dlPFC) improves dual task walking in older adults, when tested just after stimulation. The acute effects of tDCS on the cortical physiology of walking, however, remains unknown.

Methods: In a previous study, older adults with slow gait and executive dysfunction completed a dual task walking assessment before and after 20 min of tDCS targeting the left dlPFC or sham stimulation.

Long-term Tai Chi Training Is Associated With Better Dual-task Postural Control and Cognition in Aging Adults.

Objective: Many activities within our daily lives require us to stand upright while concurrently performing a cognitive task (ie, dual tasking). The "costs" of dual tasking can present as a detriment to either task, or even both. Evidence supports that tai chi (TC), a mind-body exercise, improves both postural control and cognition.

Diminished Locomotor Control Is Associated With Reduced Neurovascular Coupling in Older Adults.

Background: Walking, especially while dual-tasking, requires functional activation of cognitive brain regions and their connected neural networks. This study examined the relationship between neurovascular coupling (NVC), as measured by the change in cerebral blood flow in response to performing a cognitive executive task, and dual-task walking performance.

Methods: Seventy community-dwelling older adults aged 84 ± 5 years within the Maintenance of Balance, Independent Living, Intellect and Zest in the Elderly (MOBILIZE) Boston Study were divided into LOW (n = 35) and HIGH (n = 35) NVC.

Lower cerebral vasoreactivity as a predictor of gait speed decline in type 2 diabetes mellitus.

Gait speed is an indicator of overall functional health and is correlated with survival in older adults. We prospectively evaluated the long-term association between cerebral vasoreactivity and gait speed during normal walking (NW) and dual-task walking (DTW) in older adults with and without type 2 diabetes mellitus (T2DM). 40 participants (aged 67.

Executive Network Activation is Linked to Walking Speed in Older Adults: Functional MRI and TCD Ultrasound Evidence From the MOBILIZE Boston Study.

Background: Changes in cerebral blood flow velocity (CBF) in response to a cognitive task (task-related ΔCBF) have been shown by Transcranial Doppler ultrasonography (TCD) to be reduced in slow walkers. However, it is unknown whether reduced task-related ΔCBF is associated with reduced neural activity in specific brain regions, as measured by blood-oxygen-level dependent (BOLD) functional magnetic resonance imaging (fMRI).

Methods: We assessed the regional changes in neural activity associated with reduced middle cerebral artery (MCA) task-related ΔCBF to an executive task and slow walking speed in 67 community-dwelling older adults from the MOBILIZE Boston Study.

Inflammation-associated declines in cerebral vasoreactivity and cognition in type 2 diabetes.

Objective: The aim of this prospective study was to investigate the relationships between inflammation, cerebral vasoregulation, and cognitive decline in type 2 diabetes mellitus (T2DM) over a 2-year span.

Methods: Sixty-five participants (aged 66 ± 9.2 years, 35 with T2DM, 33 women) were enrolled for this 2-year prospective study.

Dementia alters standing postural adaptation during a visual search task in older adult men.

This study investigated the effects of dementia on standing postural adaptation during performance of a visual search task. We recruited 16 older adults with dementia and 15 without dementia. Postural sway was assessed by recording medial-lateral (ML) and anterior-posterior (AP) center-of-pressure when standing with and without a visual search task; i.

Slow gait speed - an indicator of lower cerebral vasoreactivity in type 2 diabetes mellitus.

Objective: Gait speed is an important predictor of health that is negatively affected by aging and type 2 diabetes. Diabetes has been linked to reduced vasoreactivity, i.e.