Your Brain at Work - Guide on Brain Fitness

your Brain at work Making the science of cognitive fitness work for you

Putting It All Together Enrich Your Life, Enrich Your Brain

About This Report Your Brain at Work: Making the Science of Cognitive Fitness Work for You has been developed as part of a nationwide workplace program co-sponsored by the Mature Workforce Initiative of The Conference Board and The Dana Alliance for Brain Initiatives with support from The Atlantic Philanthropies. The Mature Workforce Initiative is committed to helping employers engage and develop mature employees within the rapidly changing multigenerational workplace. Our evolving work is validated by frequent interaction with our 2,000 member companies as we respond to their emerging business issues. Funding for the Initiative is generously provided by The Atlantic Philanthropies. The Conference Board is one of the world's pre-eminent business membership and research organizations. Best known for the Consumer Confidence Index and the Leading Economic Indicators, The Conference Board has, for more than 90 years, equipped the world's leading corporations with practical knowledge through issues-oriented research and senior executive peer-to-peer meetings. The Dana Alliance for Brain Initiatives is a nonprofit organization of more than 265 neuroscientists who are committed to advancing public awareness of the progress and promise of brain research and to disseminating information about the brain in an accessible fashion. The Dana Alliance, supported entirely by the Dana Foundation, does not fund research or give grants. The Atlantic Philanthropies are dedicated to bringing about lasting changes in the lives of disadvantaged and vulnerable people through grant-making. Atlantic focuses on critical social problems related to aging, disadvantaged children and youth, population health, and reconciliation and human rights.

introduction

Put your brain to work and it will work for you

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e’ve all seen the news: we can affect how our brains work. Neuroscience tells us that we can increase our chances

of maintaining our mental edge and functional independence throughout our lives. How? By working to keep our brains fit the way we work to keep our bodies healthy. What you do every day matters to your brain. The choices you make, your level of physical and mental activity, your social life, diet, and sleep habits—all these things can affect cognitive fitness: a state in which we are performing well mentally, emotionally, and functionally. Your Brain at Work connects the latest research to practical suggestions for incorporating healthy brain habits at work and at home. Good choices can help you maintain cognitive vitality in every area and at every stage of your life. Because you are working, you’ve already taken the first step. A brain at work is a brain that works. The mental and social stimulation of the workplace help keep your brain fit.

If you already have a wellness or fitness program at work, this material can add a brain health component to it, or become the basis for a new wellness program. On your own, you can use this booklet as a personal cognitive fitness tool kit. Your Brain at Work includes basic brain facts, a readiness quiz to determine what sort of brain lifestyle you’re living, chapters on brain health, and an action plan to help you use this information wisely and well. Brain health is a lifelong commitment, and it’s never too early to begin. Or too late. Practicing cognitive fitness will help you stay on top of your game, on the job and off. In this booklet, we are going to show you how.

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Table of Contents 3 Readiness Quiz 4 Meet Your Brain If you don’t know your cerebrum from your cerebellum, have no fear

8 What Does It Mean to Be “Brain Fit”? It’s true after all: use it or lose it

12 Move Your Body When you work out your body, your brain benefits

16 Meet, Greet & Be Social Your brain needs social connections

20 Work Your Brain They’re called brainteasers for a reason…

2 Your Brain at Work

24 Feed Your Brain Food for thought: diet matters

26 Stress Management Relax! It’s only your brain we’re talking about

30 Sleep, Rest Well To sleep, perchance to retain new information

36 How Can You Put It All Together? Enrich your life, enrich your brain

40 Summary: It’s Never Too Late or Too Early to Begin

41 An Action Plan for Brain Health

43 Glossary

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Readiness Quiz Answer these questions, and read on to find out why your answers are important, and where they put you on the continuum of brain health. At the end of the book, you’ll get an action plan that will help you incorporate diet, exercise, and cognitive stimulation into a healthier brain lifestyle. 1. How much did you move today? Include every time you were ambulatory, from jogging on a treadmill to walking around your office. ____________ ______________________________________________________________ ______________________________________________________________ 2. How many social interactions did you have today? Include contacts with your co-workers. _______________________________________________ ______________________________________________________________ ______________________________________________________________ 3. Did you practice any new skills on the computer at work today? Work a crossword puzzle? Do an ordinary task in a new way? ________________ ______________________________________________________________ ______________________________________________________________ 4. If you are like most people, you probably do three things at once. But do you know what recent studies have revealed about multitasking? ______ ______________________________________________________________ ______________________________________________________________ 5. Did you eat any blueberries today? Fish aside, do you know what foods are brain-healthy? ______________________________________________ ______________________________________________________________ ______________________________________________________________ 6. How much sleep did you get last night? Was it uninterrupted sleep? Do you often feel drowsy during the day? _____________________________ ______________________________________________________________ ______________________________________________________________

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Meet Your Brain motor cortex cerebral cortex

sensory areas

frontal lobes parietal lobes

occipal lobes

temporal lobes cerebellum

Some of the brain areas involved in cognitive processes are shown here (and described at right).

Credit information: Image courtesy NINDS/National Institutes of Health.

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If you don’t know your cerebrum from your cerebellum, have no fear

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n the past decade alone, neuroscience has revolutionized our understanding of the normal structure and functioning of the brain, how it changes as we age, and what can go wrong in neurologic or psychiatric disease states. At the same time, the brain is truly one of the last frontiers in biological science, still rife with mysteries about its inner workings. Cerebral cortex: the brain’s heavily folded outer layer of gray matter, critical to cognitive processing

Parietal lobe: perceives and interprets bodily sensations such as touch, pressure, pain, and temperature

Sulci: the shallow grooves in the cortex; the central sulcus divides the two hemispheres

Temporal lobe: involved in memory processing and interpreting sounds

Gyri: the ridges on the cortex

Occipital lobe: seat of the visual cortex, which detects and interprets visual stimuli

Cerebellum: facilitates movement, coordination, balance, and posture, and appears to be involved in some types of learning Frontal lobe: controls higher thought processes and executive function

Hippocampus: part of the brain that developed early in evolutionary history; involved in learning and short-term or working memory Motor cortex: part of the cerebral cortex that controls movement Your Brain at Work 5

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What’s clear is that each of us has a brain that is unique. The overall anatomy and location of key brain structures is similar across the population, but the pattern of connections among nerve cells — the synapses by which brain cells talk to one another — is the singular product of our individual life experiences. Each of our brains, no matter our age, is a work in progress. It responds and adapts and literally rewires itself in accordance with what we put into it — what we learn, what we say, what we do, how we interact with others, and even what we eat. Scientists call this “plasticity.” It’s the reason we can affect our cognitive function when we take the steps to do so. Take learning, for example. When we learn something new, and we learn it well, our brain literally creates a particular pattern of synaptic connections for that learning. It’s as if the phone number of your boss or the route to your parents’ house stakes out its own piece of real estate in the brain — but it’s more of a highway than a building lot.

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Each new experience we encounter, if it is repeated often enough, will be represented in the brain with its own signature pathway of nerve connections. These connections interlink and may overlap with many (sometimes many thousand) other pathways that are in some way associated with that experience. This is why repeating something we want to learn, or associating it with other things that will jog our memory, can improve the “laying down” and later recall of the thing we’re trying to remember. Synapses that don’t continue to be activated fade away. If your boss’ number changes, or your parents move, the associated neural real estate will likely be up for sale, at least after a while. This is the “use it or lose it” concept. Some things may be indelibly carved into our neural circuits — like real estate permanently designated for a specific use. You may still remember the phone number of the home you grew up in, even if you haven’t used it in years. So, too, emotionally charged memories may be especially strong and enduring.

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Drive a Cab, Expand Your Brain A classic example from the annals of brain science showing how experience can shape the brain is a 2000 study performed on London cab drivers,1 who have highly refined abilities for navigating a large, complex city. Using magnetic resonance imaging (MRI), researchers at University College, London, found that cab drivers’ hippocampuses — part of the brain involved in spatial memory and navigation — were significantly larger compared with those of other people. The longer the taxi driver had been on the job, the larger his hippocampus was. A number of studies have documented changes in the part of

the brain’s motor cortex that maps activity in the hand among musicians who play string instruments or the piano; it is even possible to determine what instrument an individual plays by looking at the pattern of structural change in the motor cortex.2 Other studies suggest that practicing a skill in the mind’s eye only — visualizing a specific series of finger movements, for example, rather than actually performing them — has a corresponding effect on brain structure in the relevant region. Such studies have become classic examples of how one’s life experiences literally shape and reshape the brain.

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What Does It Mean to Be

“Brain Fit”?

Notes from the lab Research studies in many countries have found four factors that may predict maintenance of cognitive function.

1. Increased mental activity 2. Increased physical activity 3. Increased levels of social engagement 4. Control of vascular risk by: a. Controlling weight b. Monitoring cholesterol c. Monitoring blood pressure d. Not smoking

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It’s true after all: use it or lose it

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veryone knows what a fit body looks like, but fit brains, which don’t boast rippled muscles or six-packs, are tougher to distinguish. Brain fitness is a state of mind in which we are performing well cognitively and emotionally. When we’re cognitively fit, we’re maintaining our mental edge, staying sharp, aging successfully. Brain fitness is not only the absence of disease, either Alzheimer’s or other types of dementia; it is also the preservation of emotional and cognitive well-being throughout our working years and beyond.

Your brain at work is in a win-win situation. Any cognitive stimulation you receive in your workplace is like a daily workout for your brain. And the more fit your brain is, the better prepared you are likely to be to cope efficiently with the daily challenges of life and work.

Developing a healthy brain attitude and lifestyle has benefits at every stage of life, in virtually every aspect of our lives. The sooner we begin, the better, but we can reap the benefits regardless of when we start, just as physical exercise can improve physical health at any age. Whether you are in your 30s or your 50s or even older, you may be able to improve your cognitive vitality.

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The Fundamentals of Cognitive Fitness The basics of cognitive fitness lie in fundamental healthy-brain practices, such as physical activity, social interaction, mental stimulation, a brain-friendly diet, healthy sleep patterns, and stress management. Benefits from such practices range from cellular and biochemical changes at the level of neurons and synapses to “whole-brain” changes, such as denser neural networks or more efficient neural processing. These kinds of physiological alterations may be manifested as improved cognitive functioning — better memory, faster learning, greater attention and focus — and as emotional well-being.

The bottom line is that a brainhealthy lifestyle is a combination of many factors, each of which has its own benefits to the brain. When combined, the benefits are likely to be additive: The more brain-healthy practices you follow, the greater the benefits. Of course, no one can guarantee that adopting a brain-healthy lifestyle will absolutely ensure good cognitive health until your dying day, but the potential benefits of shaping up your brain are increasingly welldocumented. In the following pages, we’ll show you how to put these scientific findings to work for you.

“If we maintain cognitive function over time, then we are more likely to be functionally independent.” Marilyn Albert, Ph.D., Professor of Neurology and Psychiatry, Director of Cognitive Neuroscience, Johns Hopkins University School of Medicine

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physical activity

Cognitive fitness is a state of mind in which we are performing well mentally, emotionally, and functionally. Attaining it entails following healthybrain practices, such as exercising the mind and body, staying socially connected, eating and sleeping well, and managing stress.

social interaction

mental stimulation

diet

adequate sleep

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Physical Activity

Move Your BODY! Notes from the lab What if simple exercise could boost the rate at which your brain makes new neurons? Columbia University researchers have found provocative evidence that structured aerobic exercise does exactly that3 – and we’re not just talking about rodents on a wheel. Neuroscientist Scott Small and his colleagues put 11 adults through 40 minutes of aerobics four times a week for 12 weeks, then measured blood flow in the participants’ brains. Small’s team wanted to know whether the exercise would help generate new neurons in the hippocampus (a process called “neurogenesis”), as had previously been shown to occur in animals. Since there’s no way to measure neurogenesis directly in humans, the researchers did a parallel study in mice, examining their brains after they were allowed to exercise freely for two weeks (mice actually like exercise). They found blood flow changes in the animals’ brains that correlated with the degree of neurogenesis that had occurred. Then they compared these changes to those in the humans’ brains. The patterns matched closely, convincing scientists that they were seeing the first surrogate representation of increased neurogenesis in the human hippocampus. What’s more, the blood flow changes in the brain correlated with both cardiopulmonary and cognitive fitness. Conclusion: increased blood flow to the hippocampus may trigger or support new neuron growth, which in turn may improve learning.

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When you work out your body, your brain benefits

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f you haven’t yet heeded the message to get moving, here’s one more good reason to do so: Increasing your level of physical activity is one of the best things you can do for your brain. You don’t have to run a marathon or develop Popeye-like muscles; even a half-hour of moderate physical activity (think: walking briskly) will help. Strive for that much every day. How Exercise Helps The last few years have seen an explosion of scientific evidence for the brain benefits of exercise, leaving little doubt that increasing physical activity is Job No. 1 for everyone interested in maintaining cognitive function. Studies in humans and animals have found that exercise: Enhances memory and learning, demonstrated by better performance on a range of cognitive tests. Improves mood and counteracts depression. There is substantial evidence for the antidepressive qualities of regular aerobic exercise, and government-funded clinical trials are underway to investigate exercise as a treatment for depression, alone or in combination with antidepressant medications.

Enlarges blood vessels to pump more blood and oxygen into the brain. Increases levels of brain-derived neurotrophic factor (BDNF), a growth factor that supports and nourishes brain cells. Ramps up the rate at which new nerve cells are generated in the hippocampus, and increases the volume of the hippocampus. Increases the number of glia, brain cells that support neurons and speed neural processing.

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How much exercise is needed?

The answer continues to be debated, but most experts agree that striving for at least 30 minutes of moderate exercise daily, four or more days a week, is sufficient to improve brain health. Most human studies on the brain benefits of exercise have had people doing aerobic exercise for 45 minutes to an hour, three or four days a week, but it’s important to keep in mind that

any exercise is better than none. If you can’t find an hour to devote to it, think piecemeal: Start with three 10-minute walks over the course of the day. Aerobic exercise such as swimming, cycling, or brisk walking that raises the heart rate for a sustained period is best, probably because it floods the brain with oxygen-rich blood.

“There is increasing research in human and animal studies to suggest that physical activity and exercise will protect your mind and brain throughout your lifetime.” Art Kramer, Ph.D., Professor of Psychology, University of Illinois, Urbana-Champaign 14 Your Brain at Work

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No time in your workday for

working out? Be creative. Fit in a little exercise whenever you can, even while at work. For example:

Use work breaks or lunch times to go for a walk.

Stand up and walk around while talking on the phone; you can also do leg lifts, extensions, or arm curls to work your muscles.

Park your car a distance from your workplace and hoof it.

If you work at home, walk around the block.

Visit co-workers in person instead of phoning or emailing.

Skip the elevator and take the stairs.

Use the restroom that is farthest from your desk.

Use commuting time to practice deep breathing and good posture.

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Social Interactions Meet, Greet, & Be Social

Notes from the lab What’s in a leader’s brain? What’s different about the brain of a visionary leader? Can the characteristics of leadership be defined and mapped onto the brain? If so, can we change our own brains to resemble those of outstanding leaders? That is the theory behind emerging neuroscience research driven largely by business management experts seeking new ways to foster leadership skills. Neuroscientist Robert Thatcher and Arizona State University business professor Pierre Balthazard are among those trying to harness the brain’s inherent plasticity to build a better business leader. Their idea is to map patterns of electrical activity across brain regions to see how leaders differ, then develop training programs targeted at those areas. Subjects undergo psychological assessment to identify leadership attributes, then answer questions while having an electroencephalography (EEG) scan. EEG uses noninvasive electrodes to read brain electrical activity and translate it into a series

of spikes and squiggles on a printout. Thatcher analyzes the data to identify features that distinguish leaders. Based on early results that have not yet been published in a peer-reviewed scientific journal, leaders seem to have “a more highly developed right hemisphere” and better-coordinated neuron firing there, suggesting more efficient neural processing, according to Thatcher. Differences were particularly pronounced toward the back of the right brain, an area associated with social skills, self-awareness, and awareness of the subtleties of other people’s emotions. This suggests that “the social side of leadership” may be critical, Thatcher says. The researchers recently scanned West Point cadets to investigate whether military leaders are unique. And Balthazard is working on training programs to help people attain a more “leader-like” brain through a combination of traditional leadership education and EEG biofeedback applications.

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Your Brain Needs Social Connections

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umans are social animals. Study after study has shown that staying socially connected — that is, spending time with friends and acquaintances and participating in many social activities — is one of the fundamental tenets of cognitive health. Conversely, being socially isolated is associated with a host of health problems and shorter lifespan overall. Think about it: When you’re actively engaging with other people, you’re using your brain (How can I get him on my team?). When you’re meeting new people, you’re using your brain (What was her name?). People are good for brain health because they are unpredictable. They keep us on our toes. And we can learn something from every person we meet.

How Social Interaction May Help Scientists don’t completely understand how social interactions contribute to cognitive fitness. One theory is that social networks help us manage stress better.

When you have a strong social network, you are likely to have people you’re looking out for, and people who are looking out for you — someone to lean on in times of need. This gives us a sense of purpose and belonging, and may better equip us to cope with the curve balls life sometimes throws. Staying socially active, in the office or in the neighborhood, is also closely linked with feelings of “self-efficacy,” the sense that what we do in life makes a difference, that our life has meaning. This is another important component of cognitive fitness.

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Building Your Social Network

“Greater social resources, as defined by social networks and social engagement, are associated with reduced cognitive decline…” Conclusion from the Chicago Health and Aging Project, funded by the National Institute on Aging

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If you’re working in anything other than a one-person office, you’ve probably got a fair amount of social interaction built right into your workplace. Use this to your advantage. Engage with co-workers outside of the office; schedule weekly “coffeehouse” sessions after work, or put together an informal sports league, such as bowling or softball, to get people active and engaging with another. Some other ideas:

If you telecommute or work in a field job, there are still many ways to build in social interaction:

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Volunteer with a local charity, school, or social organization. You’ll meet new people and feel good about helping fulfill a need in your community. Take a course or workshop that puts you in touch with other likeminded people. Join a book club, garden club, professional association, or some other kind of group to pursue professional affiliations or an activity you enjoy. Stay in touch! Look up friends you’d like to reconnect with. Plan regular visits with your extended family or your circle of friends — say, Sunday night potluck dinners. Engage people — even if it’s the deli worker who serves you coffee each day.

Greet the mail carrier or delivery person, and get to know each other. Find out who else in your neighborhood works from home and plan regular get-togethers for coffee or lunch and celebrations, such as holidays or birthdays. Do your work at a local library or community workspace a few times a week. Chances are you will meet other regulars and get to know the librarians, too.

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Mental Stimulation

Work Your Brain

Notes from the lab Can training your brain really stave off cognitive decline? Spectacular claims abound, but rigorous clinical trials are harder to come by. Some convincing scientific evidence for the benefits of cognitive training comes from a large government-funded study known as ACTIVE, or Advanced Cognitive Training for Independent and Vital Elderly. In a 2006 report,4 ACTIVE researchers demonstrated that participating in a short-term but structured cognitive training program significantly improved cognitive skills closely related to the skill set targeted, and that the benefits persisted even after five years. “The improvements seen after the training roughly counteract the degree of decline in cognitive performance that we would expect to see over a seven-to-fourteen year period among older people without dementia,” the study’s lead investigator said. ACTIVE included 2,802 adults 65 and older who were randomly assigned to participate in one of three cognitive training programs that taught them strategies for improving memory, reasoning, or speed of processing. A fourth group of “controls” received no training. The training interventions involved up to 10 sessions over a six-week period. A proportion of the study participants also received four “booster” sessions over the course of the five-year study period. Each participant underwent cognitive testing before and after the interventions, and annually thereafter.

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They’re called brainteasers for a reason...

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t makes perfect sense that working your brain can help keep it sharp. Brain research is beginning to support that notion with solid scientific evidence. One of the largest studies investigating risk factors for Alzheimer’s disease (the Religious Orders Study, whose participants are Catholic nuns, priests, and brothers, age 65 and older), found that people who engaged more frequently in activities involving significant information processing — things like listening to the radio, reading newspapers, playing puzzle games, and going to museums — had a much lower incidence of Alzheimer’s disease.5 Similar results have been found in other studies. More recently, a large clinical trial investigated whether a structured cognitive training program for older adults could affect mental functioning. Participants were trained in memory, reasoning, and speed of processing. The majority did indeed

improve in the skill areas in which they were trained. Moreover, the improvements persisted long after the training stopped, suggesting a long-term benefit (see page 20).

How Mental Activity May Help How mental activity improves cognition (and reduces dementia risk in later life) is not entirely clear, but a leading theory is that it sets up a “cognitive reserve” in the brain. Intellectual stimulation drives the brain to develop denser synaptic connections. This in effect makes the brain more flexible, enabling it to use alternate neural pathways to adapt to changing demands and possibly offering some measure of protection from normal or diseaserelated cognitive changes.

“When we stimulate our brain by actively thinking, we are sculpting our own neural architecture.” Jordan Grafman, Ph.D., Chief, Cognitive Neuroscience Section, National Institute of Neurological Disorders and Stroke Your Brain at Work 21

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Putting Your Brain to Work

Despite the infant state of research in this area, “brain training” gimmicks and gadgets abound. But be careful: Very few of these products or services have been subjected to rigorous scientific studies. Brain scientists who have spent years (or decades) studying cognitive improvement strategies tend to be conservative. The database is growing, but there’s much more to be learned, including which types of activities are most beneficial and why. Based on what is known, it’s possible to formulate a few general principles. One is to engage in activities that stimulate and challenge you. Hopefully, those activities include your job. At home, your options are more varied. If Sudoku challenges you, do Sudoku. If reading a fascinating novel does, read a novel.

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Some other tips Find ways to put your brain to work every day, such as balancing your checkbook without a calculator or using a map to figure out directions, rather than getting them online. At work, learn a new software program or volunteer for a new assignment. The brain loves novelty, so seek out something new: a new hobby or craft, a new language, or a subject you’ve never been exposed to before. Adult education courses are good places to start. Many employers now offer online training on many topics. Take a selfdirected class and learn a new skill. Break out of your normal routine. This can be as simple as using your nondominant hand to eat your dinner or taking a different route to work — anything that gets your brain off autopilot. Play challenging games like Scrabble®, Concentration, or Bridge. Take up a musical instrument and either teach yourself to play or obtain some professional instruction. Explore new places and/or cultures, whether they are nearby or far away. Surround yourself with stimulating people and situations; visit museums and art galleries; attend concerts and sporting events.

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Diet and Nutrition

Feed Your Brain Here’s some food for thought: diet matters

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t’s notoriously difficult to determine which components of our abundant, varied Western diets are healthful and which are not, as evidenced by the conflicting, shifting dietary advice promulgated by an ever-changing array of experts. This is an area in which the science is continuing to emerge — meaning that what we know today may change tomorrow. Still, there are some general guidelines that most experts in this area agree on.

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“Do what your mother told you to do: Eat all those healthy fruits and vegetables!” Claudia Kawas, M.D., Associate Director of the Institute for Brain Aging and Dementia, University of California, Irvine

Vegetables

In a large government-funded study, women in their 60s who ate more green leafy and cruciferous vegetables (cauliflower, broccoli, or cabbage) did much better on cognitive tests6 10 years later. The women who ate the most of these vegetables were mentally “younger” by one to two years than those who ate the fewest.

Fatty fish Certain fish contain omega-3 fatty acids, which have been shown to have beneficial brain effects. Best sources are salmon, tuna, and mackerel. Some manufactured foods are now fortified with omega-3 fats.

Whole grains A diet rich in whole grains, such as brown rice and whole wheat bread or pasta, supports overall cardiovascular health, which is closely linked to brain health.

Blueberries This fruit is a potent source of antioxidants, which counteract celldamaging “free radicals” throughout the body. Other sources of antioxidants are most berries, walnuts, sunflower seeds, pomegranates, ginger, legumes, and colorful vegetables. Antioxidant supplements have not been proven to offer the same health benefits as antioxidant-rich foods.

Red wine Many studies have shown that alcohol, used in moderation (up to1–2 glasses a day), may be beneficial to the brain.

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Stress Management Notes from the lab Meditation is a proven stress management technique, and has been shown to improve cardiovascular health and even boost immune function. But what can it do for your brain? Landmark studies with Tibetan Buddhist monks uncovered intriguing clues. Richard Davidson and colleagues at the University of Wisconsin showed that “expert meditators” have a higher level of the brain waves associated with advanced mental activity such as attention, learning, and conscious perception.7 The distinct rhythms persisted even when participants were not actively meditating, suggesting that long-term meditation alters baseline brain activity.

Other research indicates that regular meditation can actually change the structure of the brain in areas associated with attention and sensory processing. A brain imaging study led by Sara Lazar 8 at Massachusetts General Hospital showed that areas of the cerebral cortex, the outer layer of gray matter in the brain, were thicker in participants who were experienced in a practice called insight or “mindfulness” meditation. The thickening was most pronounced in older subjects, suggesting that meditation could reduce the thinning of the cortex that typically occurs with aging.

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Relax! It’s only your brain we’re talking about

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one of us can expect to do away with stress entirely in our lives. But we can learn to manage it and take positive steps to blunt its impact. Often, we feel stressed when we lose a sense of control over our lives. In today’s global economy, Americans are working harder and longer than ever before. Our daily work requires relentless multitasking, and we face constant change as companies adapt to fierce competition and advances in technology. Navigating the demands of our work and our personal lives leaves many of us feeling like we are not particularly successful in either. Taking action to regain control — or choosing to let go of control — is the first step. This may require taking a hard look at what’s going on in our lives, assessing where we give up control, and deciding how much we need to have control, in any particular area. Then we can prioritize, and we can either try to change the underlying situations that leave us feeling out of control or accept that there are

some things in life that we simply have no control over. One thing we can exert some control over is attitude. No matter what is going on around us, and how much chaos seems to surround us, we can still choose to focus on the positive aspects of a situation and minimize the negative.

Your Brain on Multitasking Multitasking has become a way of life — and work — for many of us. We check email while on a conference call. Review slides during a meeting. Talk on a cell phone while we’re driving. Doing two or three things at once may have become so secondnature we don’t even realize we’re doing it. We may not be able to imagine how we would get through our day if not for this capacity to juggle.

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It may surprise you to learn that multitasking is not the most efficient use of brain power. A series of studies in recent years has used brain imaging to understand how the brain handles discrete tasks that are performed simultaneously. The results suggest that multitasking has a cost in terms of efficiency, learning, and neural activity devoted to each task. One of the most recent studies, from Vanderbilt University,9 suggests that the brain’s executive control center in the frontal lobes is incapable of processing two decision-making operations at once, effectively creating a bottleneck in information processing that delays the execution of the second task until the first one is complete. Separately, researchers at the University of California – Los Angeles reported a 2006 study10 finding that multitasking adversely affects the brain’s learning systems. Study participants, who were all in their 20s, learned a task in two

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ways: without any distractions and with the distraction of a series of beeps that they were asked to count silently. Learning the task with the distraction created a less robust memory of the task, reducing participants’ subsequent knowledge when questioned about the task at a later time. Earlier published studies show that switching from one task to another costs the brain time — the more complex the tasks, the more time it takes the brain to switch — and that when the brain engages in two tasks simultaneously, it devotes less neural activity to each task, essentially dividing its processing power rather than doubling it. The bottom line from these studies is that multitasking is inefficient at best, at least from a brain-processing point of view. Focusing on one task at a time is likely to produce better — and faster — results.

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Good Stress/Bad Stress Stress is a double-edged sword in terms of its cognitive impact. On one hand, mild stress — like an approaching deadline — tends to improve cognitive performance, focusing our attention on the task at hand. But when stress becomes chronic or unmitigated, it can damage the brain and impair memory. That’s because when we are faced

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with a serious stressor, the brain triggers the adrenal glands to release powerful stress hormones such as cortisol and adrenaline. Repeated or long-term exposure to these hormones — as happens in chronic stress or conditions such as post-traumatic stress disorder — is toxic to nerve cells in the hippocampus.

Stress Managment Techniques • Deal with situations directly. Instead of complaining, focus on finding a solution. • During stressful moments like work deadlines or commuter traffic jams, take a series of deep breaths. With regular practice, this technique may help you relax during stressful situations. • Spend time with co-workers away from work. Getting friendly may make working together easier. • Take a break from stress. Walk around the block or have lunch away from work – in a park or at a nearby restaurant. Whether you are alone or with a friend, that time may help reduce the tension you’re feeling. • Try to be objective when dealing with difficult people, situations,

or decisions. Remind yourself that it’s not personal, it’s business. • Listen to calming music. If you can bring in an iPhone, do it. • Avoid caffeine – coffee, tea, chocolate, etc. Caffeine can make you jittery and increase your stressful feelings. • Control what you can in your work environment. Start each day by making a plan. Set up systems to stay on top of email and voice mail. Reduce noise with headphones. Get rid of desk clutter. Make a to-do list. Getting organized may make you feel more in control at work. • If your workload is unmanageable, ask your manager to help you set priorities.

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Sleep, Rest Well Notes from the lab The idea that sleep is necessary to consolidate what we learn into long-term memories has gained significant ground in recent years, despite the difficulty of proving the hypothesis. While it’s clear that people remember better if they have a full night’s sleep, why this is so has remained largely a mystery. Recent work by Brown University neuroscientists offers fresh clues.11,12 Mayank Mehta and colleagues recorded electrical activity from the brains of mice anesthetized to mimic the deepest sleep states of humans, when memory storage is believed to occur. (The hippocampus is responsible for new learning, but scientists believe that long-term memories are stored in the cortex, and that a “filing” process happens while we sleep.)

Mehta’s team captured a startling “dialogue” of electrical communication between the cortex and the hippocampus, in which the cortex initiated a pattern of nerve firing immediately echoed by hippocampal neurons (see image at right). The work demonstrates a novel dialogue between the hippocampus and cortex during sleep, which the authors believe plays a key role in memory formation. Surprisingly, the cortex seemed to be driving this dialogue, as if it were phoning a subordinate to order up the files it anticipated needing later. Mehta speculates that this is the brain’s way of wiping clean the white-board of the hippocampus to make way for the next day’s new information.

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To sleep, perchance to retain new information

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etting a good night’s sleep — 7 to 8 hours for most adults — is essential to performing at our best. If you find yourself regularly having trouble falling asleep or staying asleep, there are some things you can do to address the problem. How Sleep May Help What the brain does during sleep is one of the enduring questions in neuroscience research, and we don’t have all the answers yet. But a growing body of evidence suggests that a full night of restful sleep is critical for memory consolidation and retaining information. In studies, people who are deprived of sleep generally score significantly worse on memory and cognitive

tests — and the deficits may not be reversible even after the participants are allowed to sleep. If, after a week or two, you still can’t sleep, see your doctor. You could have a sleep disorder, such as obstructive sleep apnea or restless legs syndrome. Identifying and treating the cause of your sleep disturbance can help get you back on the road to a good night’s sleep.

While you were sleeping… experiments in sleeping mice show a remarkable degree of synchronization between patterns of nerve firing in the brain’s cortex (blue trace) and hippocampus (red trace), with hippocampal activity immediately following cortical oscillations. In the background is a hippocampal neuron of the type from which data were recorded. This study was undertaken by Brown neuroscientist Mayank Mehta, in collaboration with Thomas Hahn and Bert Sakmann. (Image: Mehta/Hann/Sakmann/ Brown University).

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These tips can help you get a good night’s sleep Go to bed and get up at about the same time every day, even on weekends.

Don’t eat or drink large amounts before bedtime.

Avoid nicotine and caffeine.

Exercise regularly.

Make your bedroom cool, dark, quiet, and comfortable.

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Sticking to a schedule helps reinforce your body’s sleep-wake cycle and can help you fall asleep better at night. Eat a light dinner about two hours before sleeping. If you’re prone to heartburn, avoid spicy or fatty foods, which can make your heartburn flare and prevent a restful sleep. Also, limit how much you drink before bed. Too much liquid can cause you to wake up repeatedly during the night for trips to the bathroom. These are addictive stimulants that can keep you awake. Smokers often experience withdrawal symptoms at night, and smoking in bed is dangerous. Avoid caffeine for eight hours before your desired bedtime. Your body doesn’t store caffeine, but it does take many hours for it to eliminate the stimulant and its effects. Regular physical activity, especially aerobic exercise, can help you fall asleep faster and make your sleep more restful. Don’t exercise within two hours of your bedtime, however. Exercising close to bedtime may keep you awake longer. Create a room that’s ideal for sleeping. Adjust the lighting, temperature, humidity, and noise level to your preferences. Use blackout curtains, eye covers, earplugs, extra blankets, a fan, a humidifier, or other devices to create an environment that suits your needs. Continued on page 34 Your Brain at Work 33

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a good night’s sleep Continued from page 33

Sleep primarily at night.

Choose a comfortable mattress and pillow.

Start a relaxing bedtime routine.

Go to bed when you’re tired, and turn out the lights.

Use sleeping pills only as a last resort.

Source: Mayo Clinic (www.mayoclinic.com)

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Daytime naps may steal hours from nighttime slumber. Limit daytime sleep to less than one hour and don’t nap later than 3 p.m. If you work nights, keep your window coverings closed so that sunlight, which adjusts the body’s internal clock, doesn’t interrupt your sleep. If you have a day job and sleep at night but still have trouble waking up, leave the window coverings open and let the sunlight wake you up. Features of a good bed are subjective and differ for each person. But make sure you have a bed that’s comfortable. If you share your bed, make sure there’s enough room for two. Children and pets are often disruptive, so you may need to set limits on how often they sleep in bed with you. Do the same things each night to tell your body it’s time to wind down. This may include taking a warm bath or shower, reading a book, or listening to soothing music. Relaxing activities done with lowered lights can help ease the transition between wakefulness and sleepiness. If you don’t fall asleep within 30 minutes, get up and do something else. Go back to bed when you’re tired. Don’t agonize over falling asleep. The stress will only prevent sleep. Check with your doctor before taking any sleep medications. He or she can make sure the pills won’t interact with your other medications or with an existing medical condition. Your doctor can also help you determine the best dosage. If you do take a sleep medication, reduce the dosage gradually when you want to quit, and never mix alcohol and sleeping pills. If you feel sleepy or dizzy during the day, talk to your doctor about changing the dosage or discontinuing the pills.

Your Brain at Work 35

How Can You Put It All Together?

Notes from the lab Even if life sometimes feels like a rat race, people as a rule are a bit more evolved than rodents. But at the most fundamental levels of brain function – the dance of molecules, proteins, and electrical signals that drive cell-to-cell communication in the brain – we’re not so different from our four-legged friends. It’s reasonable to presume that generally, what’s good for their brains is good for ours as well. So what can we learn from decades of animal research chronicling the brain benefits of “enriched environments” that we can put to use in our lives? If we could create the perfect enriched environment in which to work, what would it include? Think about how you can adapt your own work-style (and life in general) to incorporate principles of good cognitive health in each of these areas: • Working more physical activity into your day, including aerobic exercise, stretching, and moving your body whenever possible. • Stimulating and challenging the mind by learning something new and seeking out novel experiences or different ways of doing routine things. • Maintaining plenty of interaction with other people, including meaningful social engagement and connections with friends and loved ones. • Managing stress and finding positive ways of coping with high-stress periods. • Being mindful of your diet and sleep habits, working in brain-healthy foods on a daily basis, and giving your brain the sleep it needs to stay alert and attentive.

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Enrich Your Life, Enrich Your Brain If you had your own personal cognitive fitness trainer, what kind of a training program would he/she put you on?

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learly, cognitive fitness is multidimensional. It’s more than physical activity. It’s more than mental stimulation. And it’s more than social interaction, diet, stress management, or adequate sleep. Each of these factors is important, but even more important is putting them all together.

Just as taking care of your body involves more than exercise alone, taking care of your brain demands a multifaceted approach. The more you do to take charge of brain health, the more you are likely to benefit.

The good news is that by making simple changes in your day-to-day life, you can reap the benefits of cognitive fitness.

The Team Approach to Brain Health While no single activity is going to give you total cognitive fitness, activities that combine physical exertion with new learning and social engagement are likely to offer additive benefits beyond activities that focus on only one of these factors.

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A number of studies have suggested that participating in group dance lessons improves cognitive functioning. For example, researchers at McGill University in Montreal presented data at a 2005 scientific meeting showing that older adults who learned Argentine tango dancing experienced improvements in cognition and day-to-day task performance. Tango combines social integration (dancing with a partner; participating in a group class) with mental challenge (learning complicated dance steps) and physical exercise requiring balance and coordination. One of the largest studies to look at the benefits of combining various factors known to affect cognitive fitness is a clinical trial by Johns Hopkins University called

38 Your Brain at Work

Experience Corps,13 which recruits older adults as volunteer mentors for elementary-school students in13 cities across the country. The volunteers play roles designed to have a high impact on children’s educational outcomes, providing the participants an opportunity to make a real difference in a child’s life. At the same time, Experience Corps increases the volunteers’ social, cognitive, and physical activity. Preliminary results from the study show that the older adults participating in Experience Corps scored significantly better on cognitive tests than a group of control subjects who did not participate. They also got physically stronger, had higher levels of physical activity, and expanded their social networks.

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Learn Faster, Remember Better Such studies extend a long history of research examining animals that are raised in so-called enriched environments — cages that are filled with toys, running wheels, and tunnels, and that are shared with other animals. Mice or rats who are exposed to such stimulating environments, which give them ample opportunity for exercising voluntarily, playful exploration, and interacting with others of their species, show significant benefits over animals raised in standard cages without the extra stimulation. Specifically, they learn to run a maze faster and more accurately and to better remember the best path through the maze.

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When researchers look at the brains of animals raised in these complex environments, they find increased numbers of synapses, larger blood vessels, higher levels of neuron-supporting brain chemicals, and other physiological changes indicative of improved neural functioning. Enrichment of this sort even boosts the number of new neurons that are generated in the hippocampus, a phenomenon that is associated with better learning.

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summary

It’s Never Too Late or Too Early to Begin When should you start training your brain? Yesterday!

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s cognitive fitness research progresses and expands, we can expect more specific guidelines on just what types of work and leisure activities are most beneficial, how often to do them, and why they affect brain health. In the meantime, it is encouraging to know that, just by making simple changes in your day-to-day life, you can take control of your brain health and reap the benefits of cognitive fitness. It’s never too late or too early to begin. And the sooner you start, the more you stand to gain. We hope this booklet has helped you identify goals for making your brain fit for life – by spending more time on such brain-boosting activities as exercise and socializing, or even learning something new. Now let’s focus on steps to help you reach those goals. You will find a convenient action plan format at the end of this discussion. Fill it out by using the following steps.

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Your Cognitive Fitness Strategy An Action Plan for Brain Health Write it down. Putting your goals in writing makes them more meaningful. Adding why you want to achieve each goal is a real motivator. Take baby steps. You’ll feel overwhelmed if you try to address every aspect of brain health at once. Set priorities. Give yourself a timeframe. And remember: That implies giving yourself enough time to work at and master your goals. Be realistic. People who try to do too much too soon often get discouraged and give up altogether. Don’t be a victim of your own ambition. If your goals seem impossible, revise them. Now, determine your baseline. Think about how you measure up against the healthy brain practices below. Social Interaction • Who did I see today, and for what purposes? • What did I do to reconnect with someone I care about today? Physical Activity • How many minutes did I walk today, including around the office? • How did I work exercise into my

day? • Did I “walk and talk” at work, rather than emailing or phoning? Cognitive Stimulation • What did I learn today? • What routine task did I approach differently today? • Did I challenge my mind? Did I do anything just for fun? Diet • I ate ___ servings of fruits and vegetables today. • 3 brain-healthy things I ate today are: _________________________ Stress Management • How was my stress level today? • What caused me the greatest stress today? What triggered it? • How did I cope? How did I relax? Sleep • How well did I sleep last night? How long? Did I awaken during the night? • If sleep was poor, do I know why? • Did I feel drowsy during the day? • Did I nap? How you answer these questions may help you determine which areas of brain health you need to focus on as you map out your cognitive fitness plan. Your Brain at Work 41

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Your Action Plan for Brain Fitness Goals: __________________________________________________________ ________________________________________________________________ Action steps: ____________________________________________________ ________________________________________________________________ Timeline (when you will assess your progress): ________________________ ________________________________________________________________ Revise goals or set new ones: ______________________________________ ________________________________________________________________

Whatever your cognitive fitness focus turns out to be – more exercise, more stimulation, more social contact – you can pursue your goals at work as well as at home. Use these ideas to fill your work week with brain-boosting activities. Monday Conduct a “walking meeting” at the office, rather than a sit-down session with a colleague.

Thursday Card games are a great way to exercise your brain. Challenge a colleague at lunch.

Tuesday Shake things up! Volunteer to collaborate on a project you don’t know much about, or learn a new software program.

Friday Sharpen your communications skills by answering your emails with a phone call instead of pushing the “Reply” button.

Wednesday Bring a bag of blueberries to enjoy during a coffee break. Additional resources about cognitive fitness and healthy brain practices. You’ll find suggestions for additional reading at the end of this booklet. They can help you gain a deeper understanding of the many issues raised here, or help you find out more about what actions you can take to improve your brain at work and keep it fit for life.

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Glossary Alzheimer’s disease (page 9): a degenerative brain disease of unknown cause and the most common form of dementia. Alzheimer’s disease usually starts in late middle age or in old age as memory loss involving recent events, then progresses over the course of five to ten years to a profound intellectual decline characterized by dementia and personal helplessness. Antioxidant (25): A substance, such as vitamin E, vitamin C, or beta carotene, thought to protect body cells from the damaging effects of oxidation. Cardiovascular (25): of, pertaining to, or affecting the heart and blood vessels. Cognitive function (1): a general term pertaining to functions of the brain, including thinking, perceiving, recognizing, conceiving, judging, sensing, reasoning, and imagining. Dementia (9): general mental deterioration from a previously normal state of cognitive function or psychological factors (not to be confused with mental retardation or developmental disability). Alzheimer’s disease is one form of dementia. Dendrites: short nerve fibers that project from a nerve cell, generally receiving messages from the axons of other neurons and relaying them to the cell’s nucleus. Glia [glial cells] (13): the supporting cells of the central nervous system, which protect and nourish neurons and are increasingly believed to be directly involved in the modulation of nerve signaling. Hippocampus (7): structure located deep in the brain and involved in memory and learning. Magnetic resonance imaging (MRI) (7): A brainimaging technique that measures metabolic activity in neurons and constructs an anatomical image based on the data. Functional MRI is an adaptation of the technique that can identify which areas of the brain are active during specific tasks, thereby providing data on brain function in addition to anatomy.

central nervous system, neurons are responsible for the transmission of nerve impulses. Unlike any other cell in the body, neurons consist of a central cell body as well as several threadlike “arms” called axons and dendrites, which transmit nerve impulses. Scientists estimate there are more than 100 billion neurons in the brain. Neuroscience (1): the study of the brain and nervous systems, including their structure, function, and disorders. Neuroscience as a discipline has emerged only in the last few decades. Obstructive sleep apnea (31): recurring interruption of breathing during sleep because of obstruction of the upper airway by weak or malformed pharyngeal tissues. It occurs especially in obese middle-aged and elderly men, and results in hypoxemia and in chronic lethargy during the day. Plasticity (6): in neuroscience, refers to the brain’s capacity to change and adapt in response to developmental forces, learning processes, or aging, or in response to an injury in a distinct area of the brain. Restless legs syndrome (31): feeling of uneasiness and restlessness in the legs after going to bed (sometimes causing insomnia); may be relieved temporarily by walking or moving the legs. Self-efficacy (17): an individual's estimate or personal judgment of his or her own ability to succeed in reaching a specific goal. Synapse (6): the junction where an axon approaches another neuron or its extension (a dendrite; see definition above); the point at which nerve-to-nerve communications occurs. Nerve impulses traveling down the axon reach the synapse and release neurotransmitters into the synaptic cleft, the tiny gap between neurons. Transcendental meditation (26): a technique, based on ancient Hindu writings, by which one seeks to achieve a relaxed state through regular periods of meditation during which a mantra is repeated.

Neurons (10): nerve cells. The basic units of the

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Acknowledgements The following individuals and groups contributed extensively to the production of this guide.

The Conference Board Mature Workforce Initiative Team Linda Barrington, Ph. D. Lorrie Foster Diane Piktialis, Ph. D. Jeri Sedlar Mary Young, Ph. D. Wennie Lee Katherine Solis

Your Brain at Work Links/other resources Dana Alliance for Brain Initiatives http://www.dana.org/about/dabi Learn more about this nonprofit organization of more than 265 pre-eminent neuroscientists, including ten Nobel laureates, dedicated to advancing education about the brain.

Publishing Department Peter Drubin Sana Olkovetsky Chuck Mitchell Susan Stewart

The Dana Alliance for Brain Initiatives Barbara E. Gill Laura Reynolds Sarah Thompson Brenda Patoine, writer Katherine L. Bick, Ph. D., scientific advisor

MetLife www.MetLife.com Download a copy of Met Life’s Ten Tips for Maintaining a Healthy Brain. National Institutes of Health www.Nih.gov Links to all of the NIH websites, and a list of web-based health resources, listed by topic.

The Brain Center http://www.dana.org/braincenter.cfm Your gateway to the latest research on the human brain.

National Health and Wellness Bureau http://www.nhwb.org/ Information on Employee Wellness programs.

Brain Information and Brain Web http://www.dana.org/brainweb/ Visit this section to access links to validated sites related to more than 25 brain disorders.

National Heart Lung and Blood Institute www.nhlbi.nih.gov A quiz on the role of exercise in heart and overall health.

Brain Resources for Seniors http://www.dana.org/seniors/ Older adults and caretakers can find a central bank of sites about brain health, education, and aging.

National Sleep Foundation www.sleepfoundation.org General information on the importance of good sleep and tips and resources.

Brain Awareness Week http://www.dana.org/brainweek/ Learn more about this international event organized by the Dana Alliance.

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My Pyramid (the United States Department of Agriculture) http://www.mypyramid.gov/ Customize your own “food pyramid” and get tips for healthy eating.

References 1. Maguire, Gadian, Johnsrude, Good, Ashburner, Frackowiak, Frith. Navigation-related structural change in the hippocampi of taxi drivers. Proc Natl Acad Sci USA. 2000; 97(8):4398-4403. 2. Bangert, Schlaug. Specialization of the specialized in features of external human brain morphology. Eur J Neurosci 2006; 24(6):1832–1834. 3. Pereira, Huddleston, Brickman, Sosunov, McKhann, Sloan, Gage, Brown, Small. An in vivo correlate of exercise-induced neurogenesis in the adult dentate gyrus. Proceedings of the National Academy of Sciences of the USA 2007; 104(13):5638-43. Epub ahead of print March 20, 2007. 4. Willis, Tennstedt Marsiske, Ball, Elias, Koepke, Morris, Rebok, Unverzagt, Stoddard, Wright; ACTIVE Study Group. Long-term effects of cognitive training on everyday functional outcomes in older adults. JAMA 2006; 296(23):2805-14. 5. Wilson, Mendes de Leon, Barnes, Schneider, Bienias, Evans, Bennett. Participation in cognitively stimulating activities and risk of incident Alzheimer’s disease. JAMA. 2002; 287(6):742-8. 6. Kang, Ascherio, Grodstein. Fruit and vegetable consumption and cognitive decline in aging women. Annals Neurol. 2005; 57(5):713-20. 7. Lutz, Greischar, Rawlings, Ricard, Davidson. Long-term meditators self-induce high-amplitude gamma synchrony during mental practice. Proceedings of the National Academy of Sciences of the USA 2004; 101(46):16369-73. Epub ahead of print Nov. 8, 2004. 8. Lazar, Kerr, Wasserman, Gray, Greve, Treadway, McGarvey, Quinn, Dusek, Benson, Rauch, Moore, Fischl. Meditation experience is associated with increased cortical thickness. Neuroreport 2005;15(17):1893-7. 9. Dux, Ivanoff, Asplund, Marois. Isolation of a central bottleneck of information processing with timeresolved MRI. Neuron. 2006; 52(6):1109-20. 10. Foerde, Knowlton, Poldrack. Modulation of competing memory systems by distraction. Proc Natl Acad Sci USA. 2006; 103(31):11778-11783. 11. Hahn, Sakmann, Mehta. Phase-locking of hippocampal interneurons’ membrane potential to neocortical up-down states. Nature Neuroscience 2006;9(11):1359-61. 12. Hahn, Sakmann, Mehta. Differential responses of hippocampal subfields to cortical up-down states. Proceedings of the National Academy of Sciences of the USA 2007;104(12):5169-74. 13. Tan, Xue, Li, Carlson, Fried. Volunteering: a physical activity intervention for older adults – The Experience Corps program in Baltimore. J Urban Health. 2006; 83(5):954-69. © 2008 by The Conference Board, Inc., and The Dana Alliance for Brain Initiatives. All rights reserved. Printed in the U.S.A. ISBN No. 0-8237-0873-X. The Conference Board and the torch logo are registered trademarks of The Conference Board, Inc.

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