“The eye is a window to the cerebral cortex, as changes to the vascular blood flow to the retina appear related to changes in the brain” said Signorile, professor in the Department of Kinesiology and Sport Sciences (KIN). “Our work has shown that short-term (three-month) exercise interventions such as circuit resistance training can increase retina blood flow, correlating with a positive change in cognitive capacity.”
Funded by a 2021 Provost’s Research Award, this is a collaboration between researchers at the School of Education and Human Development’s Laboratory of Neuromuscular Research and Active Aging and Drs. Jianhua Wang and Hong Jiang of the Experimental Imaging Laboratory in Bascom Palmer Eye Institute, the UM Department of Ophthalmology.
“Physical activity and exercise are among the most effective, non-pharmacological tools for improving cardiovascular health and cognitive capacity in older adults,” said Signorile. “ However, the underlying mechanisms are poorly understood.”
Currently, the technical expertise and costs associated with procedures for assessing cerebral vasculature, such as magnetic resonance imaging (MRI) and computer tomography (CT) prohibit widespread diagnostic use. Fortunately, alterations in the eye’s retinal microvascular structure, volume, and blood flow are easily accessed through the transparent ocular fluid, reflecting similar changes in the vessels of the brain, said Signorile.
The new collaborative study, which begins this summer, is designed to demonstrate the responsiveness of these non-invasive, relatively inexpensive retinal markers to changes in aerobic capacity resulting from high-speed circuit resistance training over a longer (six-month) time period.
“We hope to demonstrate the viability of retinal scans as cost-effective and accessible clinical and research tools for assessing the effectiveness of different exercise programs,” said Signorile. “Additionally, this work will allow for monitoring of the microvascular changes over time, allowing more precision in designing exercise programs to target cognitive function.”
Signorile has more than 25 years of research experience in the development and application of diagnostic and prescriptive exercise procedures for special populations, such as older persons with Parkinson’s disease. His research team was one of the first to recognize that the functional declines and histological changes that occur with age reflected loss of velocity rather than simple strength, thereby dictating power or high-speed training.
“Changes in the cerebral microvasculature are known to be major contributors to cognitive impairment,” said Signorile. “Therefore, quantifying exercise-induced changes across the cerebral microvasculature, and the levels of cognitive improvement associated with them, would provide insightful information to both clinicians and researchers.”