In the search for the causes of age-related dementia, many studies are coming up with somewhat unusual conclusions. So, what does Viagra and cataract surgery have in common? A recent study showed that elderly men who used Viagra were somewhat less likely to experience early-onset dementia. Another study found that elderly people who had cataract surgery were also less likely to experience age-related dementia.

The link between Viagra and fending off dementia may be simply a physical one: Viagra improves blood flow, which can affect various organs and parts of the body. More blood flow to the brain may mean a delay in the dementia process. 

But the link between cataract surgery and dementia is more difficult to understand. A theory is that brain stimulation, whether visual or verbal, can slow down the brain processes that result in dementia. Those who have had cataract surgery often report brighter and more colorful vision than before. In addition, with improved vision an older person may venture out more and experience more stimulation simply through interaction with others. 

Supporting the theory that brain stimulation may be a factor in fending off dementia, another recent study found a surprising link: if a person is suffering from dementia, it is significantly more likely that the spouse of that person will also develop dementia. Since there seems to be no physical reason why this would occur, a theory is that the decrease in mental acuity of a spouse causes the other spouse to cut back on the activities that would assist in delaying dementia. If both spouses now spend more time at home because one spouse has dementia, and both decrease the time they spend interacting with others, the non-dementia spouse also suffers earlier mental decline.

What these studies indicate is that understanding mental decline is not simply a matter of examining the physiology of the brain. We all know older people who remain mentally active despite their physical age, and often that occurs when a person’s brain is frequently  stimulated, such as through interaction with others, doing cross-word puzzles, or playing bridge or some other card game. Perhaps the brain is like a muscle: if not used, it tends to atrophy.