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Why does memory decline?

As we grow older, we grow in wisdom. But at the same time, our brain grows smaller and smaller - by about 2% each decade. Luckily, this shift in cerebral size is a natural part of the aging process, and it happens so gradually that we don't really notice it.

One part of our brain, the frontal lobe, seems to age more quickly than other parts of our brain. By age 80, the frontal lobe loses approximately 25% of its earlier size! Since it is responsible for brain functions like response, problem solving, judgment, and attention, the frontal lobe's aging may be one of the main reasons why some older people have trouble recalling names or facts. Another aging brain trait is a breakdown in communication between brain cells, or neurons.

Research has also turned up evidence that as we age, our brains may go into what is called a seesaw imbalance. Like a seesaw, our brains teeter and totter between paying attention to the tasks in front of us and being distracted by fleeting thoughts, daydreams, or outside stimuli. So, as we get older, our brains may become less efficient at staying balanced on this seesaw, which can make it harder to perform tasks related to memory, such as making sense of new information, storing it away, and then retrieving it later.

Thus, as we age, we may also easily forget a new neighbour's name or a few items we meant to fetch at the market. Or we might flub the date more often. Unless there is an underlying problem - trauma or injury, infection, development of dementia or Alzheimer's disease - most so-called "senior moments" can be blamed on natural aging of the brain and are nothing to worry about.

But forgetting the names of loved ones is a different story. So is not being able to recall having visited the market at all, or not knowing what year it is. These are the type of forgetfulness that signal more serious problems.

Other causes of memory loss or forgetfulness include stroke, head trauma or injury, thyroid diseases, certain medications, depression or anxiety, alcoholism, poor diet (e.g., vitamin B12 deficiency), and sleep disorders. Low levels of high-density lipids, better known as HDL or "good" cholesterol, has also been linked to poor memory. And some researchers believe that changing levels of the female hormone estrogen may create memory difficulty, especially after menopause and during pregnancy.

Despite this natural aging process, our brains remain quite adaptable to change, allowing us to learn new things, make new connections, and to fend off memory loss. And we can give our brain the help it needs by following good habits for a healthy memory.

Habits for a healthy memory

When someone says "memory," we tend to think of a thing, like the "misty, water-coloured memories" of song. Memories can be nostalgic images and visions we recall, or bits of facts, figures, and knowledge we've accumulated. Or it can be like this space inside of our head where we tuck treasured thoughts away, a kind of mental file cabinet.

But when it comes to keeping your memory healthy, it's good to think of memory as a verb - remembering. To remember, to create a memory, is active - to make sense of a new piece of knowledge, store it away in our brains, and retrieve it later when we need it. And to keep our memory robust and agile, we need to be active and proactive.

We need to move often. You can't literally jog your memory. But our brains absolutely love exercise. When we exercise, our brains get a workout right along with the rest of our body. Regular physical activity helps us to reach or maintain a healthy weight, improves circulation, and keeps cholesterol and blood pressure in check. Some research has shown that if you were to get a brain scan right after your workout, you would see your brain lit up with activity, and some parts may have even grown in volume! To really get the most memory power out of exercise, try activities that integrate three big brain benefits - movement, learning new skills, and socializing. Think partner or group dance classes, martial arts, or team sports like soccer and softball.

We need to socialize. Social isolation among the elderly may be to blame for at least some degree of cognitive impairment that happens with age. Evidence supports this, and people who forge ties to others tend to experience less memory decline as they get older. Whether it's a deep, stimulating conversation or just a chat with neighbours on the way to the mailbox, socializing is about making a connection. Our brains thrive on these connections. Interacting with others engages so many parts of our brains: we listen, we watch, we read facial expression and body language, we hunt for the right word to describe emotions or sensations, we call up past events, we reach out to touch and shake hands or give a goodbye fist bump. All of this communication provides the brain with mental exercise.

We need to relax. You know that feeling in your body when you're tense? Tight shoulders, clenched jaw, et cetera? Well, your brain feels the strain, too. Chronic anxiety or depression can cause the brain to be constantly bathed with the stress hormone cortisol. Some evidence shows that all of that cortisol may cause a part of the brain's temporal lobe, the hippocampus (which helps us stow short-term memories so they'll turn into long-term ones), to shrink. To de-stress, cultivate relaxation techniques, like meditation or yoga. Or organize your time to minimize stress using day planners, to-do lists, and handheld digital devices. And don't take on more than you can effectively manage.

We need to sleep. While relaxation is a conscious and focused effort, real rest should be a purely unconscious thing! Deprive yourself of good sleep and you're more likely to experience memory loss. Not to mention that when you're overly tired, it's hard to deal well with stress, which we know can affect memory, too. But get plenty of sleep, and you allow your body and brain to be rejuvenated and replenished. Even a quick cat-nap has its brain benefits. Doze for just 5 to 10 minutes, and you may be able to better remember something you've recently learned or memorized. A longer lay-about, and you'll get an energy and concentration boost. Snatching a snooze for more than 45 minutes may hone your declarative and procedural memory - that is, it might be easier to remember and explain facts and to perform physical tasks you've just learned, like sewing, playing a tune on the piano, or dancing the tango.

We need to eat well. As it goes with exercise, so it goes with food: What's good for the heart is good for the brain! In that case, we should feed our memories foods that are lower in artery-clogging saturated and trans fats, like lean protein and whole grains. We must remember to up our intake of the beneficial fats, including omega-3 fatty acids found in fish, nuts, and olive oil. Vitamin- and antioxidant-packed fruits and vegetables should find their way into every meal and most snacks. The brain will gladly gobble up foods rich in B vitamins, like folate, B12 (cobalamin), and choline. And vitamin E, especially when coupled with vitamin C, has been linked to reduced cognitive decline with aging. Of course, everything should be taken in moderation - some studies suggest that high-calorie diets may increase the risk of disorders like Alzheimer’s or Parkinson’s.

We need to sip smart. Faced with a mentally challenging, memory-dependent task, you may feel tempted to down a coffee or caffeinated energy drink. While caffeine can perk you up, it might actually undermine your memorizing and recall efforts. One study showed this stimulant may impair an important chemical messenger in the brain that helps us to recall newly-created memories. And though it's said that some drink to forget, one study showed people who drink occasional alcoholic beverages may have a memory advantage over those who never drink.

And we also need to seek out and tackle cognitive challenges. Grab some tips, tricks, and strategies for this brain-building habit here.

Change your mind: memory tips and tricks

When you challenge your mind, you build up a collection of memory strategies - a "cognitive reserve," if you will. So when you're faced with struggles to remember something, you can have plenty of tricks up your sleeve to help you through.

With most of the healthy habits mentioned here, memory is an active pursuit, like exercising, eating right, and socializing. But the mental work of memory building - that's memory as a thing; a set of skills to be learned. And there's no truth to the old saying about old dogs and new tricks! Learning remains possible as we age. By practicing brain-boosting strategies, we may actually be able to "change our minds" - to create new connections between our brain cells.

Organize your brain's filing cabinet: As we get older, it's common to have trouble fetching facts from our brains. Since our retrieval skills slip gradually, we may not even notice the change. To keep retrieval sharp, try these tricks:

  • file memories well: Just like it's easier to find a file in a neatly organized filing cabinet, it can be easier to retrieve a memory if we file it in the right way. When you learn something new, put it together with something you already know. Attach a word, picture, or memory to it. To remember where you parked at the mall, look around for guideposts - signs, numbers, natural landmarks. Or if you meet a woman named Florence, remember her name by thinking of a trip you took to Italy or envision a bouquet of flowers. Or file her face away with other folks you know whose names begin with "F."
  • say your ABCs: Stuck for Florence's name when you run into her at the post office? Go through the alphabet in your head until you hit on a letter that feels familiar. Same trick works for recalling which movie you saw that character actor in or which month your niece's birthday falls in.
  • access memories often: The memories we turn to less often will tend to fade into the background, but those we use repeatedly tend to stick. So, if there's a memory you want to hold, repeat it and rehearse it in your mind. Do this with phone numbers, addresses, names, or rules for an upcoming driving test.

Organize your environment: You may feel surprised or downright upset when you can't track your keys for the umpteenth time. "What's wrong with me? Am I losing it?" you may wonder. But maybe it's not your brain that's out of order. Maybe it's just your environment. Set aside one (and only one) spot in your home where you stash your keys. Avoid late fees at the video store and library by stowing rented items on a particular shelf that you pass by often. Post refrigerator reminders or set alerts on your computer for refilling prescriptions or restocking your laundry room.

Work and play with your brain: Like an unexpected challenge, engaging in brain-bending problem-solving activities can build new connections and improve memory retention. Give yourself permission to play games and solve puzzles. Crosswords, Sudoko, trivia challenges, reading - anything that perplexes and poses questions will do the trick. Add in a social component to your mental exercises, like joining a book club, taking a course to learn a new language, or competing in a trivia competition.

Look to the future: Prospective memory - the ability to remember to do something in the future - may slip as we age. Any way you can grab onto the future, do it! Calendars, day planners, personal digital assistants, and computers with built-in reminder alerts can help day-to-day, as can any old-fashioned written reminders like to-do lists and grocery lists. And it wouldn't hurt to practice the tricks mentioned above for these types of new memories. Worried about remembering to go to your dentist appointment next Thursday afternoon? Picture your dentist acting on your favourite show that you watch on Thursday nights. Or repeat "3 pm Thursday" over and over until it's impossible to forget!

Look to the past: Jotting down lists is one way to keep track of future events, but what about remembering the past? So-called remote memories - childhood stories, the first day you met your mate, your post-university jaunt around Europe - can sometimes fade, too. Indulging in nostalgia and writing down memories can help us to hold onto those distant events. Dig up old, tattered letters or newspaper clippings you snipped out years ago. Choose a journal to pen your personal memoirs or open up a word processing document on your computer. Pull out your old diaries from high school or socialize with friends and family on Facebook, at reunions, or over coffee.

Embrace unexpected challenges: While routine is a strong memory booster, breaking your routines can be just the jolt your brain needs sometimes. Travel to a new place, even if it's just in your own hometown. Shop at a different grocery store or take a switched-up, back-road route to a place you visit often. Take a bus tour, a cruise, or take in a show at a local theatre. Your brain loves a challenge, and new experiences make for a great mental workout.

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