Brain health experts explain why cognitive decline may be more reversible and preventable than we previously believed.
Many of us have been taught to think of the brain the way we think of an old car: first useful, then slowly wearing out until breakdown is inevitable. Forgetting is natural. Dementia felt like fate. Aging itself was treated as a one-way street.
The last section Longevity. Technology OPENhosted by Dr. Nina Patrick and Phil Newman, pushes hard against this narrative. In a conversation that moves from ballroom dancing to Alzheimer’s prevention, neuroscientific advances to deeply personal patient recovery, two leading brain health experts argue that the adult brain is far more adaptable than most people realize, even in old age.
“We were basically told that the adult brain can’t change,” says Dr. Henry Mahnke, the company’s CEO. BrainHQ and one of the scientists behind the landmark ACTIVE study. “When that critical plastic period ended, the brain was wired like a computer chip. And everything it did after that was worn out.” This assumption, according to him, is now dispelled.
This episode Mahnke and neurologist Dr. Majid Fatuhi, associate physician at Johns Hopkins University and author The invincible brainwhose clinical work combines cognitive training with lifestyle interventions designed to improve long-term brain function.
Together, they describe a growing scientific shift: away from seeing cognitive decline as inevitable and toward understanding the brain as learnable, responsive, and biologically dynamic.
At the center of the debate is the ACTIVE trial, one of the most important long-term studies of cognitive learning ever conducted. The results, published earlier this year, showed that a particular form of “speed training” was associated with a 25% reduction in the incidence of dementia over 20 years.
For Mahnke, the discovery felt personal. “My grandfather died of Alzheimer’s disease when I was about 10 years old,” she said. “That’s part of the reason I do what I do.”
The training itself seems simple. Participants are shown rapid visual tasks on a screen and asked to identify objects and spatial details under increasing time pressure. However, beneath this simplicity lies a great neuroscientific principle: the brain changes when it is pushed to the edge of its capacity.
“It should be harder than that,” says Mahnke, explaining why the challenge of adaptation is important. “If you get 10 out of 10, we won’t help you.”
The analogy he keeps coming back to is physical exercise. Just as cardio strengthens the heart through repetitive strain and recovery, cognitive speed training strengthens the brain by making it process information more efficiently. Faster processing, he says, isn’t just about mental clarity; it reflects healthier neural circuitry. “Strengthening the brain makes it healthier,” he says.
However, one of the most interesting moments of the episode comes not from the laboratory, but from Fatuhi’s clinic. He recalls meeting a seventy-year-old woman named Carol, who had withdrawn from everyday life. Her family believed she had Alzheimer’s disease and were preparing to move her to a nursing home, but Fatuhi suspected something more complicated was going on beneath the surface.
“He just sat there,” she recalls. Upon further investigation, he discovered a number of contributing issues: depression, chronic pain, sleep apnea, medication overload, and metabolic disorders. Carol enrolled in a 12-week program that combined cognitive exercises with optimized sleep, movement, socialization and nutritional support.
Little by little she changed. “He started talking more. He started walking more,” says Fatouhi. “When she finished the program, she was a new person.”
Then came the MRI. Fatuhi says the scans showed that his hippocampus, an area of the brain heavily involved in memory formation, had grown significantly in size in just 12 weeks. Later, after reconnecting with an old boyfriend and rebuilding his social life, it grew again.
The story almost sounds too cinematic, but this is at the heart of modern brain health science. Researchers increasingly document that the brain remains biologically responsive throughout life, while public understanding often lags decades behind.
“The more you exercise your brain, the stronger it becomes,” says Fatouhi. “It’s never too late.” Importantly, neither visitor presents brain training as a silver bullet.
Fatuhi identified cognitive training as one of five pillars: physical training, restorative sleep, Mediterranean-style nutrition, stress reduction, and targeted mental training. Just one crossword puzzle, they both say, is unlikely to significantly alter the risk of dementia. It is important to have a stable connection at the same time in several systems.
There is also something radical about the aging debate of both speakers. Their vision of the afterlife is not just about living longer, but remaining mentally active, emotionally and intellectually engaged.
Fatuhi calls this transformation “brain talk,” whose cognitive function remains decades younger than expected. The idea may sound ambitious, but the episode confirms that the greater danger lies elsewhere: assuming that decline is inevitable and giving up before the brain even has a chance to respond.
New series Longevity. Technology OPEN drop by every Monday featuring the researchers, founders and clinicians shaping the future of aging science. A weekly news roundup is published every Friday. Find it Apple Podcasts, Spotify and YouTube.
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