Revealed: The ‘mentally stimulating’ tasks you need to do twice weekly to prevent dementia

What activity has been shown to ward off dementia in a new study? Clue: It’s one across and has nine letters.

In a recent study, doing a crossword at least twice a week was found to dramatically slow cognitive decline in older Americans compared to those who did this less often.

Other ‘mentally stimulating’ activities like reading a book, playing Sudoku or journaling also appeared to protect against the decline.

It’s thought that these activities can help form new brain cells and boost connections in the brain responsible for memory. 

Researchers in three states followed nearly 6,000 adults over 50 for almost a decade and divided them into groups based on how often they participated in ‘cognitively simulating’ activities.  

Though all participants suffered memory decline with age, those who regularly picked up a book or a puzzle had consistently better memory and slower rates of cognitive decline over an eight-year period.

This lowered their risk of mild cognitive impairment (MCI), which can lead dementia in as many as nine in 10 patients. 

Dementia plagues more than 7million Americans per year, along with almost 1million Brits. And about 10million Americans and one in five Brits over 65 are diagnosed with MCI. 

Dr Jungjoo Lee, lead study author and assistant professor at the University of Southern Mississippi, told PsyPost the findings indicate that ‘the cognitive care program needs a comprehensive design that includes physical activities, cognitively stimulating activities, and community engagements.

‘Balanced therapeutic strategies incorporating all these healthy behaviors will boost cognitive health benefits rather than focusing on a single domain.’ 

The study, published earlier this year in the Journal of Cognitive Enhancement, followed 5,932 adults recruited from the Health and Retirement Study (HRS), a database on aging Americans, from 2012 to 2020.

Participants ranged from 50 to 109 years old, with an average age of 68. 

The team measured cognitive function by looking at memory, working memory, and attention and processing speed. 

Working memory is how long someone can hold on to temporary information, such as remembering an address while being given directions. 

Attention and processing speed measure how quickly the brain takes in information, such as letters while reading a book. 

Researchers measured these factors based on how fast they could recall words, basic math skills, and tasks like counting backwards. 

Participants were then divided into groups based on how often they did tasks like crossword puzzles or reading a book.

Though all participants saw memory declines, those who completed these activities more than twice a week ‘consistently presented higher memory working memory, and attention than groups that participated less in the activities,’ Dr Lee said.   

It’s unclear why exactly these activities slowed cognitive decline, but experts believe they may help stimulate brain cell growth and strengthen connections between brain cells responsible for memory.

There were several limitations to the research, with the main one being that researchers did not account for other factors that could have caused cognitive decline, such as other health issues, medication use, and unforeseen events like accidents. 

Additionally, there was a significant age range among the participants, with the youngest being just 50 and the oldest 109. As the risk of cognitive decline increases with age, this could have led to bias. 

Dr Lee said: ‘Futher investigation is required to control internal and external confounders affecting healthy behaviors and each cognitive function.’