You have probably heard that engaging in mentally stimulating activities helps fight against dementia, especially by delaying the onset of the disease. How do we know that? Here is a typical study, published in 2009, in which researchers examined how education and stimulating activities interact to fight against cognitive decline.
The study involved 488 initially healthy people, average age 79, who enrolled in the Bronx Aging Study between 1980 and 1983. These individuals were followed for 5 years with assessments every 12 to 18 months.
At the start of the study, all participants were asked how many cognitive activities (reading, writing, crossword puzzles, board or card games, group discussions, playing music, etc) they participated in and for how many days a week.
Researchers were able to evaluate the impact of self-reported participation in these activities on the onset of accelerated memory decline in 101 individuals who developed dementia during the study.
For every “activity day” (participation in one activity for one day a week) the subjects engaged in, they delayed for about 2 months the onset of rapid memory loss associated with dementia.
Interestingly, the positive effect of brain-stimulating activities appeared to be independent of a person’s level of education.
It is never too late!
This is great news as this study suggests that it is never too late to start brain-stimulating activities! Even if you did not get the stimulation that higher education may provide to your brain early on, engaging in stimulating activities later in life can also protect the brain. The more brain-stimulating activities one does and the more often, the better.
Why would these activities have a protective effect on the brain?
The idea is that stimulating the brain helps build cognitive reserve. Individuals with more cognitive reserve seem to tolerate more pathology in the brain (these plaques and tangles associated with Alzheimer’s Disease) without developing Alzheimer’s Disease symptoms, compared to individuals with less reserve.
How does that work? Scientists offer two possibilities:
1. More cognitive reserve may mean more brain reserve, that is more neurons and connections between them. Individuals with more connections (synapses) would then have more of them to lose before the critical threshold for Alzheimers’ symptoms to appear is reached.
2. More cognitive reserve may also mean more compensatory processes. The brain of individuals with more reserve would use more alternative networks to compensate for the damages caused by the pathology in previously used networks.
Hall, C. B., Lipton, R. B., … & Verghese, B. S. (2009). Cognitive activities delay onset of memory decline in persons who develop dementia. Neurology, 73, 356-361.