Playing a mental speed-training game seems to help the brain clear a protein linked to Alzheimer’s disease in men, but may work in women through different mechanisms.
A cognitive “speed training” game that cuts dementia risk by 25 per cent alters levels of beta-amyloid, a protein that clogs up the brain in Alzheimer’s disease, in men, but not in women.
It is the first time brain training has been shown to influence the levels of a neurodegenerative marker, strengthening the evidence suggesting that mental exercises can boost brain health.
“One of the main markers that’s indicative of future dementia risk got better for men who completed cognitive speed training,” says Hye Won Chai at Clemson University in South Carolina, who presented the research at the Alzheimer’s Association International Conference in London on 12 July.
The computer-based speed training involves recalling where objects have flashed up, with the task becoming harder as performance improves. A prior 20-year study by some of Chai’s colleagues showed that people aged 65 and older, who did the training were 25 per cent less likely to be diagnosed with Alzheimer’s disease or a related form of dementia compared with a control group.
In the latest study, Chai and her team recruited a separate group of 53 people from the US aged 65 and older, 13 of whom were male. About a third of the participants were asked to complete between 2 and 4 hours of speed training each week for 4.5 months.
The remaining participants were either told to spend the same amount of time playing games such as Solitaire, word search and a game similar to Connect 4, or to complete another kind of brain training in which they had to strategically track objects and switch between tasks.
To explore how speed training may reduce dementia risk, the team collected blood samples from all of the participants at the start and end of the training period.
This revealed that, among men, speed training increased the ratio of two forms of beta-amyloid found in the blood, which suggests the training boosted the brain’s ability to clear beta-amyloid 42. This protein forms clumps called plaques in the brain during Alzheimer’s disease, disrupting brain function. The other two kinds of training had no effect.
“It’s a really cool finding,” says Sasha Novozhilova at McGill University in Montreal. “It is definitely strengthening what they’ve [previously] shown with the reduction in dementia.”
Some Alzheimer’s treatments, such as lecanemab, have been designed to help clear amyloid from the brain, but they only marginally slow cognitive decline during Alzheimer’s disease. The limited benefit seen in trials is probably down to these treatments being taken at a relatively late stage of the condition, when substantial brain damage has already occurred, says Andrea Castegnaro at University College London.
Engaging in cognitive training to reduce beta-amyloid build-up before dementia develops may have a bigger effect on dementia because it would be done before much brain damage has occurred, says Castegnaro.
However, cognitive training had no effect on amyloid levels in female participants in the study. This suggests that speed training reduces dementia risk in different ways in women and men, says Chai.
The team hopes to explore how speed training may benefit women in future studies, says Chai. But first, the findings need to be verified in geographically and ethnically diverse groups, says Novozhilova.