Q: What causes memory loss (both in the form of diseases such as dementia and in simple situations such as where you forget where you put your keys)?
A: Some decline in memory functioning is normal over the lifespan. A neuropsychologist can identify "normal age-related changes" beginning in the seventh decade (patients who are over 60). But these should be slight changes and not the sort of forgetfulness that has real functional impact. Frank forgetfulness is not normal in older patients and should not be dismissed. Among older patients, memory complaints may be related to reversible causes or more serious and progressive decline (dementia). Common reversible causes of forgetfulness among older adults include poor B vitamin absorption, sodium imbalance, and sluggish clearing of medications. Progressive memory decline is typically related to two common types of pathology: vascular changes (tiny strokes or insufficient blood and oxygen supply to brain tissue) and abnormal protein plaques and tangles. When the plaque-and-tangle changes are significant, doctors call that Alzheimer's disease.
And even among healthy older (and not so old) adults, transient forgetfulness may be a red flag of stress, depression, or overwork. Some people notice that after a poor night's sleep, or a night of drinking too heavily, they experience memory lapses and word-finding problems.
Just over 70% of the human brain is dedicated to "what is." We take note of the room temperature, what people around us are wearing, the nature of things as they are. The rest of our brain - the prefrontal cortex - is all about "what could be." I could end an unsatisfying relationship. I could move to Phoenix. I could move the piano over there so the door could open more easily into the room. The prefrontal cortex is the home of all that is magic about human cognition. And when our lives fall into a rut of predictability - when we're not solving problems and asking "what could be" questions, we run the risk of declining cognitive efficiency.
Q: What exercises/activities do you recommend to patients to sharpen memory and prevent or delay the onset of dementia etc.?
A: Several lines of research are coming together to suggest that complex mental activity is associated with reduced dementia risk. Cognitive Training refers to prescribed sets of mental activities directed at sharpening memory skills, reasoning, and speed of processing. Informally, many clinicians have encouraged their older patients to “stay active” by keeping their brain busy with crossword puzzles or Sudoku.
But in a recent study, Susann Rohwedder and Robert J. Willis discuss what they call "mental retirement." In the winter 2010 issue of Journal of Economic Perspectives (Abstract here and NY Times article here), Rohwedder and Willis suggest that retirement from vocational activity is associated with measurable decline in cognitive ability. There may be something about work that stimulates and protects the brain against age-related decline. And that may be something that crossword puzzles and Sudoku can't approximate. Vocational activity is an excellent cognitive workout. Work presents the brain - the whole brain - with sensory demand and motor planning challenge and time management and nuanced social problems.
My advice to anyone concerned about his/her memory is first talk with your doctor. She may ask questions and chart changes over time, or may refer you to specialists for further evaluation. You and your doctor will also try to stay on top of risk factors for memory decline: monitor and regulate blood sugar, maintain normal blood pressure, and keep cholesterol in check.
Meanwhile, the type of "brain exercise" I recommend is activity which is as organic and real-life as possible. If your life is not busy enough to require an alarm clock and a planner, then you are not busy enough to maintain brain functioning. At least 5 days a week, you should have a specific reason to be out of bed, dressed, and out the door. You should have enough going on that you need to keep a calendar to keep it all straight. You should be interacting with people who are a lot like you as well as people who are so different that you have to struggle a bit to figure them out. You should be solving problems every day. We need to avoid drifting into nostalgia and reminiscence; we need to keep imagining "what could be." That's what keeps our prefrontal cortex tap-dancing. Social problems, traffic logistics, travel planning, meal preparation....all of these give your brain the workout it needs to stay healthy.
The emerging concept of neuroplasticity recognizes that experience shapes our brain. Literally, at the level of the cell and synapse and brain structure itself, our daily learnings are shaping our brains. And although our brains don't regenerate as quickly and thoroughly as skin or even bone tissue, we do now recognize that the brain makes effort to heal itself and adapt to ongoing changes. At the risk of sounding trite, "use it or lose it."
Here's a real life story that illustrates the point (with identifying information changed of course!) Marion was surprised to find how dull retirement was. After looking forward to early retirement for several years, she found herself physically healthy but, at age 58, not as busy and engaged as she'd been while working a clerical position at a community college. She began to notice minor aches and pains and checked in with her doctor about these. She'd had checkups but had never had many complaints before, and her doctor questioned clinical depression. Marion complained of some amotivation and malaise but no real sadness. She did confide with her doctor, though, that she'd begun to worry about her memory. She slipped up with words that “I ought to know” and misplaced items in her apartment. She later recalled that she had started to see herself as “old,” and didn’t put much effort into grooming or maintaining her wardrobe. She’d been dedicated to her work at a local college and without that piece of her life, she realized she didn’t have many social outlets.
Marion responded to an ad in a local weekly paper to volunteer as a “baby cuddler” in a neonatal unit. The hospital was about a half hour drive from her home which she didn’t mind if she left early enough in the morning. She loved holding the newborn babies and felt relieved that, because this was volunteer work, there was no pressure to perform. But there were other mental challenges. She now describes her surprise at the cultural diversity and the different personality types among the staff and other volunteers at the hospital. Her coworkers at the college had all been “pretty much like me.” In her volunteer work, Marion found herself navigating social challenges, avoiding “putting my foot in my mouth,” and trying to coordinate her schedule to avoid working with one particularly bossy and overbearing nurse. Most of the staff was younger and Marion loved hearing their take on movies and politics and popular culture. They teased her about dressing “frumpy” and she began to take their advice and tips. To save money, Marion packed a lunch. And this meant planning ahead, prepping the night before, and coordinating grocery shopping around her volunteer work. She began to take delight in the little day by day prizes – finding a secret parking spot near the hospital back entrance, finding the coldest soda machine in the building, and picking up a few words of Portuguese in her conversations with one of the hospital staff members. Within weeks, Marion reported that her memory seemed “back to normal,” and she even felt less focused on physical aches and pains.
For folks who are approaching retirement, then, I'd recommend considering how to keep up the kind of mental workout that vocational activity involves. For example:
Active involvement in caring for grandchildren
We need a specific reason - and deadline - to get out of bed in the morning. We need the challenge of having clean and pressed clothes ready. We need to interact with easy as well as difficult people. Our brains need problems to solve!