Welcome to The Mobility Brief, the monthly podcast from the Gray Centre for Mobility and Activity at St. Joseph's Health Care London. We're recording this on Monday, October 27, 2025. This month, we're bringing you four updates from the centre.

Next, we're going to look at the question: Can brain changes explain why doing two things at once becomes harder for people with mild cognitive impairment? A recent publication in the journal *Brain*, which Dr. Manuel Montero-Odasso engaged with, offers some perspective on this. The authors examined the relationship between brain structure and what is known as dual-task cost, which is the drop in performance when a person walks while also doing a mental task. In their response to commentary on their original research, the authors noted that future studies will use multi-voxel spectroscopy and diffusion imaging to assess different brain areas and white matter tracts. They also plan to measure cognitive performance during dual-tasking more directly with tools like digital voice capture and eye-tracking.

Now, let's shift focus to a different question: How does research on leg recovery after a stroke differ between high and lower-income countries? A publication in *Topics in Stroke Rehabilitation*, led by Dr. Robert Teasell and with contributions from Drs. Jamie Fleet, Ricardo Viana, Michael Payne, and Sue Peters, looked at this. The researchers conducted a systematic search comparing randomized controlled trials on lower extremity stroke recovery from high-income versus low-to-middle-income countries. Looking at almost 1,600 trials, they found that the number of studies from low-to-middle-income countries has accelerated and recently surpassed those from high-income countries on an annual basis. While interventions like robotic training were more frequently studied in high-income countries and acupuncture was more common in low-to-middle-income countries, the authors noted that the types of interventions were generally similar. They also observed that trials from low-to-middle-income countries were published in journals with lower impact factors, even though they had comparable quality and larger sample sizes.

And finally, another recent publication examines stroke recovery from a different angle, asking: How does brain activation change in females recovering from a stroke? This work, published in *Physiotherapy Theory and Practice*, was led by Dr. Sue Peters, and Drs. Robert Teasell, Ricardo Viana, Jaspreet Bhangu, and Jamie Fleet also contributed to the study. The researchers used a technique called functional Near Infrared Spectroscopy, or fNIRS, to look at prefrontal cortex activation in four females during inpatient rehabilitation. They measured this activation during standing and ankle movement tasks at both admission and discharge. The study found that while all participants improved on clinical measures of balance and walking, brain activation patterns also changed. For tasks performed while lying down, brain activation was lower at discharge compared to admission, while the brain's response during standing tasks was more varied.

To wrap up this month's updates, we'll look at the question: How can 3D anatomy and an analysis of dye spread be used for a patient-specific knee procedure? A publication in the journal *Pain Medicine*, led by Dr. Eldon Loh, offers visual guidance on this topic. The article describes a method for customizing knee radiofrequency ablation for individual patients by using three-dimensional anatomical knowledge together with an analysis of how a contrast dye spreads. The work presents a series of teaching images that demonstrate this patient-specific approach.

And that brings us to the end of this month's updates. We began by considering brain changes in people with mild cognitive impairment, then compared stroke rehabilitation research between high and lower-income countries. We also looked at how brain activation changes in females during stroke recovery, and concluded with a patient-specific approach for a knee procedure. From a global review of research trials to the brain activity of four females, and down to an anatomical model for a single person, these updates show different ways of looking at mobility. The methods may change, but the objective of developing a clearer view of function connects this work.

Thank you for listening to The Mobility Brief.