Written by: Hiyaguha Cohen
September 01, 2020
- There is controversy over whether exercising the brain actually prevents dementia, with research supporting both sides.
- New research from Harvard University has found that too much brain activity can shorten lifespan.
- Researchers are focused on finding drugs that can inhibit neural activity in the brain, but a healthy lifestyle can have the same effect.
Evidence that exercising the brain prevents dementia
Probably the biggest boost to the crossword industry came from multiple studies that concluded that dementia could be warded off through challenging mental activities such as reading, writing, and various types of games and puzzles. After these studies got the word out, seniors picked up pens everywhere to help maintain their mental faculties. But does brain training really prevent mental decline?
A study of 65 elderly subjects found that those who had engaged in mentally challenging tasks most often throughout their lives had less amyloid plaque buildup in the brain than those who were intellectual snails. This was especially true for those who were spiritually active in their early and middle adult years. It is important to recognize that the study did not seek or find an actual association between dementia and mental activity. While scientists theorize that amyloid plaque causes dementia, and while people with dementia tend to build up more plaque in the brain, the study made between mental activity and amyloid plaque.
Another 2014 study that enrolled 488 elderly subjects found that performing crossword puzzles in older years delayed the onset of dementia by 2.5 years. The problem was that those who did puzzles lost more memory than those who didn't. On the other hand, those who made the puzzles began their decline on a higher cognitive level. In short, the study found that taking puzzles didn't prevent dementia, but it could take a few years of clear thinking, which would still be a big deal if it were true.
Prove that exercising the brain will NOT prevent dementia
Unfortunately, not all research supports the theory that holding the brain prevents dementia. Case in point: a study published last year in the British Medical Journal tracked 498 elderly people for 15 years and regularly tested them for information processing speed and verbal memory. The results showed that those who regularly had intellectual challenges such as solving puzzles increased their intelligence in the short term, but were just as prone to dementia as control subjects. In other words, they may have been smarter than their lazy friends, and perhaps brain exercises increased their intelligence, but they were experiencing mental decline at the same rate as their friends.
Too Much Mental Activity Shortens Lifespan: New Study
And then there's the new study published in Nature that shows that the harder your brain works, the faster your biological clock is ticking and the faster you die. So much for all of this advice recommending reading and solving crossword puzzles to help ward off dementia. At first glance, you may be asking yourself, "What is the use of being able to see clearly when you're dead?"
Harvard University researchers examined the brains of hundreds of deceased people, grouped by age of death. They discovered that those who had lived the longest – e.g. Centenarians had higher levels of a gene called REST, which inhibits neuronal activity in the brain, than those who were “only” 80 years old. Expression of REST is tied to the insulin and insulin-like growth factor (IGF) signaling pathway, which tends to deteriorate with age. In any case, the scientists were surprised by the results, since they too believed that mental activity should ward off dementia and prolong life. In fact, the result was so unexpected that it took the scientists several years to publish their work as the outside scientists reviewing the research kept requesting additional data to validate the results.
The same study also included experiments on roundworms. The scientists found that when the worms increased the REST levels in the worms, they had less brain activity and lived about 33 percent longer. When the REST levels were lowered, the worms had more brain activity (considering whatever was preoccupying the worms' brains) and they died earlier. The same thing happened when the experiments were tried with mice.
However, there is a counter-intuitive kicker in this study that turns whatever you're thinking about a full 180 degrees. According to a 2018 study published in Nature Communications, the neural circuits associated with higher intelligence are sparsely and efficiently organized, which promotes more targeted information processing. Or to translate this into English, smarter people use fewer cortical activities to think and therefore are likely to live longer just because they are smarter.
Older brains are less efficient
Previous research has shown that as people get older, they need to activate additional brain circuits to get things done, compared to when they were young. The study director Dr. Bruce Yankner of Harvard Medical School explains, “On average, imaging studies show that older people have more intense and widespread brain activity when puzzling over a mental health problem, while young and even middle-aged brains are more neurologically efficient. It's like the difference between the unused movement of a champion runner and the flapping arms and legs of a weekend jogger. "In other words, older people's brains get confused more easily than younger people's brains, and that causes stress. By upregulating the REST transcription factor, people may be able to think more efficiently than they did when they were younger.
Brain activity and longevity
Should you stop reading and thinking when you are over 60? Not at all. The point is not to get stupid, but to keep the mind safe from overexcitation. Unsurprisingly, researchers are currently busy finding drugs that activate REST genes to help calm brain activity. However, it is important to note that certain natural practices can calm neural activity. For one, scientists believe that fasting changes insulin / IGF signaling, and that this in turn can activate REST activity. On the other hand, if the 2018 Nature Communication Study is to be believed, crossword puzzles and other mental exercises can do the same throughout life.
Of course, meditation can also be helpful in calming down neural activity. One of the main goals of meditation is to calm the mind. It's like taking your brain on a vacation. Advanced meditators not only silence the mind while meditating, but also train their mind to remain alert but at rest until needed. Not surprisingly, studies show meditators live longer.
Finally, exercising the body also gives the mind a break and calms nervous activity, which may be one reason why exercise is so useful in combating mood disorders.
The bottom line is that if you lead a healthy lifestyle, you are ahead of the game. Eat well so you don't get stressed out by junk food reactions, exercise, and meditation and naturally keep your mind away from hectic overactivity.