The Physical Signs That May Predict Cognitive Decline (They're Not What You'd Expect)
When we think about brain health, we usually focus on what's happening inside the brain: memory lapses, difficulty concentrating, trouble finding words. But what if the earliest signs of cognitive decline aren't in your mind at all, but in your body?
New research on sensorimotor function and cognitive health suggests that how well your senses and body work together may be a powerful indicator of brain health. And the findings point to something reassuring: the tests involved are simple, non-invasive, and already part of routine checkups.
Why sensory & motor function may reflect brain health
We already know that certain physical changes can signal cognitive risk. Hearing loss, vision changes, reduced sense of smell, slower walking, weaker grip, and poor balance have all been linked to dementia risk in past research.
But most studies looked at these factors one at a time. This research took a different approach: instead of examining each measure separately, researchers combined all six into a single "sensorimotor score" to see if the bigger picture told a clearer story.
About the study
Researchers analyzed data from two large U.S. aging studies—the Atherosclerosis Risk in Communities (ARIC) study and the Baltimore Longitudinal Study of Aging (BLSA)—totaling over 1,500 older adults. People with a history of stroke, Parkinson's disease, or dementia were excluded.
The six measures were assessed using standard clinical tests: a hearing test, a vision test, a smell identification test, a balance test (standing with feet in a line), a timed walk, and a grip strength test. Researchers then combined these into one overall sensorimotor score and looked at how it related to mild cognitive impairment (MCI)—the stage between normal aging and dementia.
Higher sensorimotor scores linked to substantially lower MCI risk
In the ARIC group (average age 79), people with higher sensorimotor scores had 47% lower odds of MCI. In the BLSA group (average age 74), the reduction was 41%. These results held up even after accounting for age, race, sex, education, BMI, and chronic conditions like heart disease, diabetes, and depression.
Importantly, the combined score was more strongly linked to MCI risk than any single measure on its own. While individual factors like walking speed or hearing showed some connection to cognitive health, the integrated score provided a clearer, more consistent signal.
How each measure connects to brain function
Each of the six measures taps into processes that require brain involvement:
- Balance: staying upright requires your brain to process spatial information in real time
- Grip strength: reflects coordination between your brain and muscles, especially in your upper body
- Walking speed: involves planning, navigating space, and executing movement
- Hearing: helps you stay aware of your surroundings and navigate safely
- Vision: supports orientation and reduces mental effort during movement
- Smell: is closely tied to memory centers and processes like impulse control
When several of these systems start to decline together, it may be a sign that the brain's ability to coordinate complex tasks is under strain—potentially before memory problems show up.
Protecting sensory & motor function as you age
This study looked at one point in time, so it can't prove that maintaining these functions will prevent cognitive decline. But it does suggest that keeping your senses and body in good shape may be part of a broader strategy for cognitive resilience:
- Get regular hearing and vision checkups: these are often overlooked but can catch early changes
- Prioritize aerobic exercise: activities like brisk walking, cycling, or swimming support heart and brain health; aim for at least 150 minutes per week (here's more on why VO2 max matters for longevity)
- Add strength training: grip strength was a key marker in this study, and resistance exercises support the brain-muscle connection; two to three sessions per week is a good target
- Practice balance exercises: tai chi, yoga, or simple single-leg stands can help improve stability
- Pay attention to smell changes: a gradual or sudden loss of smell is worth mentioning to your doctor
- Manage heart health risk factors: high blood pressure, diabetes, and high cholesterol can affect both sensory and motor function over time
The takeaway
Your senses and movement patterns may offer early clues about brain health. This research found that hearing, vision, smell, balance, walking speed, and grip strength—when measured together—were more strongly linked to MCI risk than any single factor alone. Paying attention to these physical markers could be just as important as memory exercises when it comes to protecting your brain.
