The Brain Training That Actually Lowered Dementia Risk over 20 Years

Today, we are talking about the first randomized controlled trial showing that cognitive training can reduce dementia risk for decades.

And just to be clear, we’re not talking about better memory scores next month or an improved test performance for a year.

We’re talking about a program that had a 25 percent lower risk of receiving an actual dementia diagnosis 20 years later.

No cognitive training intervention has ever shown this before. Not over this time frame. Not with real-world diagnostic outcomes tracked through Medicare claims.

This is genuinely different. Let me break down what actually worked and what didn't.

The Study That Changed My Mind About Brain Training

The trial was called ACTIVE (Advanced Cognitive Training for Independent and Vital Elderly). It randomized more than 2,800 adults age 65+ into four groups:

1. Memory training: Participants learned mnemonic strategies to better encode and recall verbal information like word lists and stories.

2. Reasoning training: Participants practiced identifying patterns and solving structured problems that required logical sequencing.

3. Speed-of-processing training: Participants completed adaptive computer tasks that trained rapid visual processing and divided attention under increasing time pressure.

4. Control group: Participants received no cognitive training and continued their usual daily routines.

Participants were followed for 20 years using Medicare claims data to track actual diagnoses of Alzheimer's disease and related dementias.

This is the longest follow-up of any cognitive training trial ever conducted. And the outcome wasn't test scores. It was real-world dementia diagnoses recorded in medical records.

Here's what happened:

Only those in the speed-of-processing training group who completed booster sessions showed a statistically significant reduction in dementia risk.

And over the 20-year follow-up, the speed-training group that completed boosters had roughly a 25 percent lower chance of receiving a dementia diagnosis than those who did no training.

Memory training? No effect.
Reasoning training? No effect.

Just speed training with boosters.

What Type of Training Actually Worked?

This wasn't crossword puzzles or sudoku.

It was adaptive speed of processing training focused on:

• Visual processing speed

• Divided attention (tracking multiple things at once)

• Rapid decision-making under pressure

• Increasingly complex information presented in shorter time windows

Here's the protocol:

Participants completed up to ten 60–75 minute sessions over 5–6 weeks. Those who completed at least eight sessions were then randomized to receive booster sessions at 11 months and 35 months after the initial training.

The dementia risk reduction was strongest in those who did the boosters.

Dose mattered. Adaptive difficulty mattered. Long-term reinforcement mattered.

Why Speed Training and Not Memory Training?

This surprised researchers too.

The leading theory is speed training targets controlled processes—things like attention, processing speed, and executive function that decline with normal aging. These are "procedural" skills that you strengthen through repetition under pressure, not explicit strategies.

Memory and reasoning training, by contrast, focused on teaching strategies such as mnemonic techniques and problem-solving frameworks. You're learning declarative knowledge: "Here's how to remember better."

But here's the thing: Early Alzheimer's affects associative memory first. If you're already in the preclinical stages, teaching memory strategies might be less effective than strengthening the underlying processing machinery.

It's like trying to teach better driving techniques versus actually improving your reaction time and peripheral vision.

What This Means for You

The takeaway isn't to casually do puzzles or download a random brain training app.

It’s to train speed and attention under adaptive pressure.

Here are some modern equivalents to the ACTIVE speed training include:

Physical activities:

• Racquet sports like tennis or pickleball (rapid peripheral awareness, split-second decisions)

• Table tennis

• Fast-paced partner dance (salsa, swing. You're tracking movement, rhythm, and spatial awareness.)

• Certain action video games that require rapid peripheral awareness and decision-making

The key variables: speed + adaptation + attention switching + dual tasking.

There are some digital options as well. The one featured in the study is: 

• BrainHQ's Double Decision module: This is the actual software from the study, now commercially available at brainhq.com (no affiliation, and I haven’t tried it.)

A Final Perspective

This was the first randomized controlled trial to track cognitive training participants for 20 years and measure real dementia diagnoses, not self-reported memory questionnaires or lab-based cognitive scores.

Medicare claims data. Actual clinical diagnoses. Two full decades of follow-up.

No other brain training study has ever shown this.

Even though more research is still needed to fully understand the biological mechanisms, this finding comes from a randomized controlled trial with 20 years of follow-up, not just an observational association, which makes the long-term link between speed-of-processing brain training and lower dementia incidence especially compelling.

And it's a reminder that your brain responds to challenge, not comfort or repetition. Challenge that adapts as you improve.

Here's to your health,
Dhru

The information in this newsletter is for educational purposes only and should not be construed as medical advice; please consult a qualified healthcare professional before making any health-related decisions.