Trying to Understand Memory Lapse

ORLANDO, Fla. - Of all the quirks of the human mind, perhaps the most annoying is the enduring mystery: Why can we remember the lyrics to the Gilligan's Island theme song but not where the car is parked at a crowded mall?

Why can some of us rattle off the projected year-end bowl game lineup-including each team's won-loss record-yet forget our anniversary?

In South Florida last month, a detective testified that it had slipped his mind that he had an audiotape clearing two men of murder. While the tape sat in a sock drawer at the deputy's home for eight months, the men sat in jail, facing the death penalty.

"I didn't do it intentionally," Broward, Fla., sheriff's Sgt. Thomas Murray insisted. "I completely forgot about it."

Human memory has always been a slippery thing, but lately it seems forgetfulness-both real and feigned-has reached epidemic proportions. Because we are bombarded by information and stress, many of our memory woes are well-earned, experts say, and a certain amount may be inevitable. But forgetfulness has also become a convenient excuse for the accused, a source of considerable anxiety for the aged, and a font of embarrassment for fumbling public speakers everywhere.

As former Vice President Dan Quayle once said, inadvertently mangling a United Negro College Fund slogan, "What a waste it is to lose one's mind. Or not to have a mind is being very wasteful. How true that is."

For all the progress scientists have made in understanding the human brain, they have only begun to understand the complicated process of memory.

"There's much more we have to learn, especially in ways like how we encode memory and where it's stored," says Dr. Patrick Gorman, a Winter Park, Fla., neuropsychologist who specializes in brain injury rehabilitation. "But there are ways to differentiate normal memory lapses from an actual memory disorder."

If you're 20 and you walk into a room only to forget what you wanted there, you most likely shrug it off. But if you do the same thing at 45 - and especially if you do it several times a week-you may start to wonder if you have early symptoms of Alzheimer's disease.

You may be tempted to think of your brain as a computer, filling up files of memory until needed for retrieval. Actually, it is both more sophisticated and more vulnerable.

Its first job is to sort which information is even worthy of memory space.

"It's not like a videocassette recorder. We don't store everything we experience," says Dr. Alan Keck, an Altamonte Springs, Fla., psychologist who specializes in everyday and traumatic stress. "There are a lot of factors that determine whether a memory gets recorded in the first place-and then whether it gets retrieved."

It may be something simple like whether you've had your normal morning cup of coffee. Whether you've slept well. Whether you're eating right or your hormones are fluctuating or you're taking medication. Many drugs-from over-the-counter allergy pills to prescriptions for heart disease and cancer-interfere with a particular neurotransmitter used to create new memories.

More seriously, certain health problems, such as strokes and depression, can cause forgetfulness.

But arguably the most common culprit is stress. The brain simply becomes overwhelmed.

Consider Gail Lenz, a stereotypically overworked, stressed-out single mom, as Exhibit A. One day a few years ago, Lenz, having just turned 40, came home from work to a stack of bills, including one from a hospital for "imaging."

"I thought, `This is obviously a mistake-and something else I've got to take care of,' " says Lenz, who at the time was the lone administrator for a busy Orlando defense contractor. "I'd had sinus surgery the year before, so I thought it was some sort of mix-up from that."

When she called the hospital, though, she was told she'd had a brain scan. It still didn't register. "Can you tell me what I had this scan for?" she asked.

"Yes ma'am," a clerk said, pulling up Lenz's medical files on computer. "You were having memory problems."

Lenz laughs about the story today, but at the time, she admits, "It felt really creepy. I thought, `Oh my God. I've lost my mind.' "

In truth, she'd just buried it under a mountain of work. While still fighting chronic sinusitis and raising two teenage sons, she was putting in 50 hours a week at her job, training 26 newly hired interns and handling construction contractors to renovate the building. To top it off, she was taking college courses at night and training for triathlons.

It got to the point where, literally, she didn't know whether she was coming or going. She'd gotten the brain scan after finding herself sitting in her car in the office parking lot one day, trying to recall whether she was leaving for lunch or just coming back.

"I just had too much to do," she says. "I was on autopilot all the time, but when you're operating that way, you're not really checked in."

Gorman agrees.

"The brain is very vulnerable to interference-from emotions, stress, hunger, fatigue, all kinds of things," he says. "Any of us, if we get overloaded, we're going to start forgetting things. A lot of people come to me thinking they have Alzheimer's disease, when they're just stressed out."

Gorman teaches them stress-reduction techniques aimed at setting priorities, releasing anxiety and getting more exercise and rest. Anything that lightens the load, he says, helps your head function better.

Plato reportedly once lectured against writing things down, arguing that the more we committed to inscription, the less we would hold in our minds.

"You know, people used to memorize the whole of The Iliad and The Odyssey, and nobody can do that anymore," says Craig Smith, a professor of communication studies at California State University, Long Beach. "We've lost the art of cultivating our memories the way that Plato talked about. I mean, I could not tell you right now what I'm doing on Friday because I don't have my appointment book in front of me. I know I have appointments, and I know they're in that book, but if I lose that book I'm dead."

It's true that most busy professionals subsist on PDAs and day-planners. But it's equally true that Plato didn't have to remember a series of passwords, screen names and personal-identification numbers-nor, presumably, to pick the kids up from soccer practice, swing by the dry cleaner, pay the cable bill, floss, put out the recycling and have his cholesterol checked.

"There's just more stuff to commit to memory than was true in the past," says Dr. Alfred Kaszniak, a neuropsychologist and head of the psychology department at the University of Arizona in Tucson. "So one of the reasons we're more concerned as a society about memory and aging is that more of us live to be older than ever before, and, second, the demands on the memory make subtle changes very apparent. We're confronted with things we need to remember all the time."

Memories are stored in various parts of the brain and linked by a series of pathways. The more pathways we develop for a particular memory, the more easily we can retrieve it.

If, for instance, you are trying to memorize various species of birds, it will be difficult to recall one from another if you merely read about them in a book. If, however, you read about the bird, write the information down yourself, read it to someone else, draw a picture of the bird or visit an aviary, you have created multiple pathways to retrieve the information. Should one path be blocked, your brain will try another.

That's why an annoying commercial jingle can stay with you for decades-because you've linked it to music as well as a feeling of aggravation. It's also why, when you encounter a familiar face but can't remember the name that goes with it, you often try to figure out where you last saw this person. If you can connect the person with the proper setting, you've used a different pathway to pull up the proper file.

"That's actually what learning is-making new neural networks," Gorman says.

The most powerful memories are those encoded with emotion, which is why people can remember, say, where they were when John F. Kennedy was assassinated or when the space shuttle disintegrated. It is also why hearing an old song can make you smile-or cry. The more senses that were involved at the time the event occurred, the more links there are.

"This explains things like post-traumatic stress disorder," Gorman says. "A Vietnam veteran may hear a helicopter overhead and suddenly he's hit with a vivid memory of being in the jungle."

The extent to which age inevitably erodes those networks is a matter of great debate. Studies show that 20-year-olds are typically able to retrieve information more quickly than 40-year-olds, but Kaszniak says there are two important caveats.

"One, there is enormous variability among older individuals. There are certainly people in their 60s, 70s and even 80s whose memory functioning is quite comparable to people in their 20s," he says. "Two, there are several things that account for that, the most significant of which is health status."

It can be hard to find enough healthy, prescription-drug-free seniors to even make a statistically significant comparison group. The average 80-year-old, Kaszniak says, is taking at least eight medications.

But researchers are identifying an increasingly long list of things that endanger memory over time-alcohol abuse, cardiovascular disease and lack of mental stimulation, to name a few.

"We now think that leading a very intellectually active life actually builds up your brain and makes it more able to tolerate the assault of Alzheimer's pathology," says Dr. Robert Wilson, senior neuropsychologist at the Rush Alzheimer's Disease Center in Chicago. "This is sometimes referred to as your `brain reserve.' "

Autopsies on people older than 85 show that three-quarters of them have evidence of Alzheimer's disease in their brains. Yet only 10 percent to 15 percent showed symptoms of the disease before they died. The difference, Wilson says, may boil down to whose brain is tougher.

And long-term depression and anxiety, in addition to causing more immediate memory problems, also seem to "wear down" the brain over time, weakening it in old age.

What if you're both intellectually stimulated and chronically stressed out?

"Well," Wilson says, "you've won half the battle."

How do you know whether a memory lapse is normal or a signal of something dire?

One way, experts say, is to consider the subject and frequency. If you can't remember where you put your car keys, you probably don't have a memory problem-although you may have a transportation problem. But if you have the keys but can't remember what they're used for, it's time to see a doctor.

It's normal to sometimes forget the names of acquaintances and things that have to do with time and space-appointments, directions, dates. But if you repeatedly forget such things, it may be more serious. At the least, says Keck, the Altamonte Springs psychologist, you need to start creating memory cues.

"I am pretty infamous among my friends and family for having a tendency to forget birthdays," he says. "So I now have a lot of cues. I have a calendar at home and I have a Palm Pilot and I use lots of (Post-it) Sticky Notes. I keep 3M in business with Sticky Notes."

The good news is that some of the most important mental abilities-such as decision-making and creativity-actually increase with age.

And Wilson says most people are lousy at evaluating their own memory skills, even those who protest they're always forgetting things. When they're given objective tests to measure how well their memory functions, those people usually do pretty well.

"So one of the things I'd say to people who are worried their memory isn't any good," Wilson says, "is `You're probably wrong.' "

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(c) 2003, The Orlando Sentinel (Fla.). Distributed by Knight Ridder/Tribune News Service.