February 24, 2026
The Telegraph
David Cox

These puzzles and exercises can all strengthen neural systems and boost cognitive flexibility – try a couple of them below

Honing your brain’s processing speed could stave off cognitive decline. That’s the key takeaway from the latest findings of ACTIVE, a US-based clinical trial examining whether brain training exercises targeting either memory, reasoning or speed of thought can keep the ageing mind healthier for longer.

The trial was carried out using specialised software developed by a US health tech company called Posit Science. Some 2,802 healthy patients who were over 65 were put through 10 hour-long training sessions with various computer game-like exercises, followed by booster sessions 11 and 35 months later. The exercises were intended to either improve retention and recall, aid with pattern recognition and problem solving, or work the brain’s ability to identify and locate visual information as quickly as possible.

The research team then used healthcare records to monitor who went on to be diagnosed with dementia over the next two decades. The results suggested that those who had participated in the visual speed training fared best, with a 25 per cent lower risk of developing dementia compared with a control group who hadn’t received any training at all.

Michael Marsiske, a clinical and health psychology professor at the University of Florida and one of the study authors, described this finding as unexpected. “The biggest surprise for me was that a relatively short burst of cognitive speed training might ripple forward for more than 20 years, showing up as fewer dementia diagnoses in medical claims records,” he says. “That kind of long-term, real-world impact from such a modest intervention is relatively unprecedented.”

The exercise used in the trial which generated the most benefit is called Double Decision, where a car and a road sign appear on a landscape for a very short period of time, and players have to accurately identify where they were on the screen. As your performance improves, it becomes progressively harder. Posit Science have also designed a series of other exercises for working the brain’s processing speed, such as Eye for Detail, which acts as a workout for your eyes and brain as the leaves, butterflies and flowers dance around the screen.

According to Alzheimer’s Research UK, the trial results must be interpreted with a dose of caution, as they don’t prove that brain exercises will prevent dementia. However, neurologist Ronald Petersen, director of the Alzheimer’s Disease Research Centre at Mayo Clinic in Rochester, Minnesota, says that the results and those of other studies indicate certain forms of brain training may delay the onset of cognitive impairment. “If it can keep you functioning at a higher level for a longer period of time, that’s probably worthwhile,” says Petersen.

So why might it work, and what other brain-stimulating games have been shown to aid cognition?

Boosting cognitive flexibility

As we age, Petersen says that our brain loses cognitive flexibility, something which affects everything from remembering people’s names to multitasking. This is driven by a variety of factors, from the atrophy or shrinkage of certain regions to the loss of connections between neurones, reducing the brain’s capacity for quick, dynamic adjustments.

The idea behind exercises like Double Decision or Eye for Detail is to give this a shake-up. “The training worked by forcing people to take in more visual information, more quickly, under tougher and tougher conditions,” says Marsiske. “Each time someone got better, the programme instantly made the task harder, which pushed the brain to speed up its processing and divide attention more efficiently, a kind of workout that strengthens the neural systems we use for everyday tasks like driving or navigating busy environments.”

You don’t even necessarily need to do them for a long time. Two years ago, a study carried out by a group of scientists at the University of Exeter showed that computerised brain training exercises are particularly good at improving attention span, while also eliciting smaller improvements in memory, thinking and problem solving. It also suggested that benefits could be achieved through spending just three minutes a day on such activities.