Mindful Walking Neural Correlates of Executive Function in SC Older Adults at Risk of Dementias

The number of older adults living with Alzheimer's disease and related dementias (ADRD) is escalating around the world, yet no effective treatment is currently available. Non-pharmacological early preventive strategies are urgently needed to mitigate the social and economic burden of ADRD and to sustain quality of life in the aging population, including the seniors living in South Carolina (SC). Mindful walking represents a promising prevention approach to sustain cognition, as it simultaneously practices mindfulness skills during physical activity (walking). However, existing mindful walking programs primarily focused on mental health outcomes (e.g., stress reduction) and overlooked the potential efficacy on cognition. This lower-intensity lifestyle physical activity may be a more viable and inclusive prevention strategy with greater scalability and long-term sustainability to serve ADRD at-risk aging populations. Our preliminary work in African American older adults around the Midlands of SC has established preliminary signals that mindful walking is feasible, acceptable, and it may sustain proximal cognitive function. However, the literature to date has not tested the neural-level correlates underlying mindful walking to infer the potential mechanism related to executive function enhancement. This is also a gap raised by a reviewer from our scored R01 in 2023 (not funded, 40th percentile). To address this knowledge gap and strengthen our R01 resubmission, our team proposes to conduct a two-arm randomized controlled pilot trial to determine the neural-level underpinning of mindful walking using the Functional near-infrared spectroscopy (fNIRS). fNIRS offers a non-invasive neuroimaging tool that uses source-detector channels placed on the scalp to measure event-evoked neural activities across the lifespan (e.g., engaged executive function while practicing mindfulness skills). fNIRS is a device that is well-suited for within-subjects repeated data collection in older adults because it is noiseless and compact, painless, and cost-effective, making it suitable to apply in a behavioral trial that requires multiple assessments. This randomized controlled trial will recruit race and ethnically diverse middle-aged and older adults who have elevated risk(s) for ADRD from the Midlands of SC. Participants will be randomly assigned to participate in 8 sessions of individual mindful walking or a walking-only control group supervised by the staff across 4 weeks. The mindful walking group will be instructed to practice simple but fundamental mindfulness skills in multiple settings to facilitate real-world skill translation (in lab, indoor, outdoor). This study will administer lab-based measures of cognitive assessments, including the fNIRS, MoCA, and NIH Toolbox Cognition Battery, to examine group differences in neural activations measured using fNIRS (Aim 1) and the concordance between executive function measured using fNIRS, MoCA, and NIH Toolbox (Aim 2). Findings from this study have the potential to provide a viable and achievable behavioral strategy that can be engaged in daily life to address cognitive health and reduce ADRD risk among underserved older populations in the Midlands of SC. It will also well-position our team to submit R01s in the following years to support this timely and critical research.

Inclusion criteria

• Age 60 or older
• Sedentary (sit ≥9hrs per day) and not meeting the US physical activity guidelines
• Have at least one of the following ADRD risk factors:

i. family history of ADRD (>= first-degree relative) ii. subjective experience of cognitive complaints iii. currently overweight or obese (BMI≥25)

• Adequate hearing, visual and cognitive ability to complete study tasks and assessments
• Able to walk without others' assistance
• Medically stable with or without medication (do not expect to have major health status changes or a surgery in the next 4 months)

Exclusion criteria

• Diagnosis of ADRD or other brain abnormalities (i.e., strokes, epilepsy, Parkinson's disease)
• Diagnosis of mental disorders (i.e., depression)
• Inability to complete surveys on mobile device or wear the activity monitor (i.e., due to arthritis, physical limitations, or other reasons)
• Plan to move or have surgery in next 4 months
• Currently participate in other study involving physical activity or cognitive training that may interfere with the study outcomes
• Unable to provide consent due to disabilities