Use It or Lose It: How Cognitive Training Builds a Resilient Brain

By Dr. Ranbir Dhillon, M.D.
Board-Certified Neurologist | Chief Health Advisor, HEALTHMAX

 

One of the most common questions I hear from patients and their families is this: "Doctor, is there anything I can do to keep my mind sharp?"

The short answer is yes. The longer answer involves a concept called cognitive reserve — a term that has profound implications for how we age, and one that I believe every adult should understand.

The idea is simple: the brain is not a fixed organ. It is dynamic and adaptable. By challenging it throughout life, you can build resilience that may help you maintain cognitive function even in the face of age-related changes or the early pathology of Alzheimer's disease. This is what scientists mean when they talk about "use it or lose it."

The Science: What Is Cognitive Reserve?

Cognitive reserve refers to the brain's ability to improvise, adapt, and find alternative pathways to complete tasks — even when some neural connections have been damaged or lost. Think of it as a backup system. Two people may have the same amount of Alzheimer's-related plaques and tangles in their brains, yet one remains sharp and functional while the other shows significant decline. The difference often lies in cognitive reserve.

A landmark study — the Nun Study — followed hundreds of nuns over decades and examined their brains after death. Researchers found that some nuns whose brains showed extensive Alzheimer's pathology had nonetheless remained cognitively intact throughout their lives. What distinguished them? In early adulthood, they had written more complex, linguistically rich autobiographical essays — an early marker of higher cognitive reserve. This study, along with many others since, demonstrated that the brain can compensate, and that this compensation is built over a lifetime of mental engagement.

More recently, the ACTIVE study — one of the largest randomized controlled trials on cognitive training — enrolled over 2,800 older adults and assigned them to different cognitive training programs. Those who received training in processing speed, memory, and reasoning showed significant improvements not just immediately, but persisting for 10 years after the initial intervention. The trained group also reported less difficulty with daily activities compared to controls.

 

What the Data Tells Us

• A meta-analysis published in Psychological Medicine examined data from over 30,000 participants and found that engagement in mentally stimulating activities — such as reading, playing games, learning new skills, or solving puzzles — was associated with a 46% reduction in dementia risk.
• A study from the University of Texas at Dallas found that older adults who spent 15 hours per week over three months learning a new, complex skill — such as digital photography or quilting — showed significant improvements in episodic memory compared to those who engaged in less demanding mental activities.
• The World Health Organization's 2019 guidelines on risk reduction of cognitive decline now formally recommend cognitive stimulation and lifelong learning as evidence-based strategies for brain health.

These findings converge on a clear message: the more you challenge your brain, the more resilient it becomes.

 

What I Recommend to My Patients

Cognitive training does not require expensive apps, brain games, or rigid regimens. The most effective mental stimulation comes from activities that are novel, complex, and engaging. Here are four evidence-based strategies:

1. Learn Something New

The key word is new. The brain thrives on novelty. When you learn a new skill — a musical instrument, a foreign language, a craft — you are creating new neural connections and strengthening existing ones. The more unfamiliar the activity, the greater the cognitive benefit. Comfort is not the goal; challenge is.

2. Engage in Activities That Combine Thinking and Social Connection

Cognitive stimulation is even more powerful when combined with social interaction. A book club, a bridge game, a discussion group, or a collaborative project combines mental engagement with the brain-boosting benefits of social connection. The combination is greater than the sum of its parts.

3. Read, Write, and Tell Stories

Linguistic complexity is one of the strongest predictors of cognitive reserve. Reading regularly — especially material that requires focus and reflection — keeps language networks active. Writing — whether journaling, letter-writing, or even composing emails — engages multiple cognitive domains simultaneously. And storytelling — sharing memories with family and friends — not only strengthens recall but reinforces social bonds.

4. Play Games, but Don't Rely on Them

Crossword puzzles, Sudoku, chess, and strategy games can be excellent mental exercise. But there is an important caveat: once a game becomes routine, the cognitive benefit plateaus. If you can do the Sunday crossword in pen, it's time to try a different kind of puzzle. Variety matters more than volume.

 

A Word to Caregivers

I know that finding time for "brain training" can feel like a luxury when you are exhausted from caregiving. But cognitive stimulation does not have to mean an hour of uninterrupted study. It can be fifteen minutes of reading before bed. Listening to a podcast while preparing meals. Learning a new recipe. Practicing a few phrases in a language you have always wanted to learn.

These small acts of mental engagement are not frivolous. They are investments in your cognitive resilience — the very resilience you need to keep showing up for the person who depends on you.