Neurologists say this simple type of training could counteract up to 10 years’ worth of “age-related declines.”
As we grow older, it’s natural for our brains to slow down a little. One major reason is the gradual weakening of the cholinergic system, a network of brain cells that supports attention, memory, and quick thinking. Scientists estimate that this system declines by about 2.5% each decade, which can translate to slower information processing and reduced mental agility. But new research from neurologists suggests that 30 minutes of daily cognitive training could reverse much of that loss in under three months.
The 2025 study, published in the peer-reviewed Journal of Medical Internet Research Serious Games, set out to explore whether targeted brain exercises could strengthen cholinergic function in healthy older adults. Funded by the National Institutes of Health (NIH) and conducted by a team from Canada’s McGill University and Posit Science Corporation in California, the research is known as The Improving Neurological Health in Aging via Neuroplasticity-based Computerized Exercise (INHANCE) trial.
Between 2021 and 2024, researchers enrolled 92 participants aged 65 and older in a double-blind randomized controlled trial. Each participant completed 35 hours of at-home training over ten weeks, using either the speed-based cognitive training program BrainHQ—focused on improving how quickly and accurately information is processed—or an active control made up of non-speeded computer games, “similar to Solitaire.”
To measure changes in the brain, scientists used a specialized PET scan to detect cholinergic binding—essentially, how well the brain’s communication system is functioning. The main area of interest was the anterior cingulate cortex, a brain region in the frontal lobe that helps coordinate attention and decision-making.
The results were encouraging. Those who completed the speed-based training showed a significant increase in cholinergic binding within that brain region, while the control group did not. In fact, the boost—about 2.3% over ten weeks—was roughly equal to reversing ten years of normal age-related decline, per the study’s text. Additional improvements appeared in regions tied to memory, such as the hippocampus and parahippocampal gyrus.
The increase may not be huge, but study co-author and McGill neurologist Étienne de Villers-Sidani, MD, told NPR that the results are still significant, especially “considering that you get a 2.5% decrease per decade normally just with aging.”
The largest study of its kind to date, the INHANCE trial is also the first to demonstrate in humans that cognitive training can restore “cholinergic terminal density”—the concentration of nerve endings that release an important neurotransmitter known as acetylcholine. Loss of cholinergic density is associated with higher rates of Alzheimer’s disease and other forms of dementia, studies show.
Beyond behavioral benefits like sharper attention and faster thinking, these findings reveal that mental exercise can lead to real biological changes by enhancing the chemical systems that support cognition. With the right kind of mental workout, it may be possible not just to maintain brain health but to reclaim some of what time takes away.