Intellectual activity and dementia: It’s more of a help than a cure.
- A remarkable seven-decade cognition studied 498 people from Scotland.
- People who test well as children retain that ranking through life.
- Study finds remaining engaged has no effect on the trajectory of dementia’s “cognitive burden.”
All of them were born in Scotland in 1936. And according to the Scottish Council for Research in Education archives, all of them took the same intelligence test on June 4, 1947 when they were 11 or 12, depending on where their birthdays fell on the calendar. (The tests were part of a nationwide survey.) A little more than half a century later, researchers from the University of Aberdeen decided to take advantage of this remarkable data set and recruited 498 of the then-64-year-olds to study the effect of intellectual engagement on one’s mental condition during later years. Their study, published online in BMJ (formerly the British Medical Journal), came to two conclusionsc:
Remaining intellectually active does not effect the likelihood of dementia or slow its physiological progression, contrary to findings of some other studies.
- Remaining intellectually active does not effect the likelihood of dementia or slow its physiological progression, contrary to findings of some other studies.
- The brain nonetheless benefits from being exercised. Should dementia eventually occur, mentally active people have more of a “cognitive reserve,” and thus it takes longer for their dementia’s symptoms to become noticeable.
As the study’s authors write in The Conversation, “‘Use it or lose it’ is the received wisdom when it comes to cognitive ability. But is there any truth in this old saw? Our latest study suggests that it depends how much ‘it’ you have to start with.”
(Staff, et al)
The study
When the study’s subjects were first recruited in 1999, they were administered the first of a series of cognitive tests. The tests were repeated at regular intervals until subjects reached age 78, or died, as 57 of them did.
Each 16-question exam assessed a subject’s intellectual state when performing four key types of mental tasks:
- Reading questions estimated the interest in, activity, and enjoyment gained from reading.
- Problem-solving questions assessed an individual’s disposition to participate in and enjoy complicated problem-solving.
- Abstract questions estimated an individual’s propensity to consider ideas and concepts in depth.
- Intellectually curious questions assessed an individual’s predisposition to learn about new topics through various media.
At the end, an overall typical intellectual engagement score was assigned each participant.
Moray House tests were the tests conducted in 1947. Education shows the number of full-time school years. For the auditory tests, the total correct score is shown. Image source: Staff, et al.
Findings of study
One type of intellectual activity seemed to give subjects the best bang for their mental buck: problem-solving. “Engagement in problem solving is an independent contributor to late life cognition and has a unique effect over and above the effect of other life course variables,” write the researchers. Memory and cognitive speed were unsurprisingly affected by age.
It also turned out that subjects with higher scores in youth tended to test similarly as older adults. “Childhood intelligence was associated with intellectual engagement,” write the study authors, “which raises the question: ‘Do smarter people engage more, or are they smarter because they engage?'”
It would appear to be the former, since, “If the latter were true in late life, then we would expect some influence on the rate of decline.” And no such effect on the rate of decline was observed.
How this helps you plan ahead
Since remaining intellectually active as you age doesn’t prevent you from acquiring dementia, why bother? Well, aside from the enjoyment to be derived from staying alert and engaged — not to mention the fun of cracking that crossword or Sudoku — it can provide a meaningful defense against dementia’s ruinous symptoms.
“At this stage, we can foresee how lifelong intellectual engagement contributes to protection from falling below some intellectual threshold where you would be considered impaired. This is achieved by starting from a higher point,” say the scientists.
