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Your Memory: Don’t Fuggedaboudit

Part of our job as doctors is to tell you things straight up, because when we don’t tell the truth, people get hurt. No sugarcoating. No BS (that really stands for no bad science). When it comes to your brain, here’s a fact that’s harsher than an Arctic winter: the research shows that, eventually, everyone in America will either get Alzheimer’s or care for someone who has it.

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When trying to determine if a family member is having serious memory trouble, ask him what he had for dinner or to describe current events, or give him three objects to remember and five minutes later ask him what they are. If he has trouble with any of those questions, it’s an indication that something’s going wrong with his short-term memory – one of the signs of a serious cognitive dysfunction.

In some way or another, we’re all going to be affected by serious change-your-life memory problems. But the other side of that statistic is this: memory disorders aren’t as uncontrollable as they seem, and the way to attack potential brain problems is by using your brain to understand them. For starters, here are some things you should know about your noggin:

We actually experience a mental decline a lot earlier than we realize. Memory loss starts at the age of sixteen and is relatively common by forty. One way you can see this is through research done on video game players. People start losing their hand-eye coordination and the ability to perform exceptionally well on video games after the age of twenty-five. The fascinating part of this research isn’t that you’ll rarely beat your kid in Mario Kart: Double Dash; it’s that even if your brain knows what to do when presented with an animated hairpin turn at 135 mph, your brain can’t fire those messages fast enough to your trigger-happy thumbs. There’s a natural slowing of the connection – the power line – between your brain and your body.

Men and women differ not only when comes to movie tastes and erogenous zones, but also when it comes to mental decline. Men usually lose their ability to solve complex problems as they age, while women often lose their ability to process information quickly. That split shows us a couple of things. One, that there’s certainly a strong genetic component to memory loss. And, two, that there are specific actions you should be taking to combat that genetic disposition. While there are some places where you’re naturally going to decline because of your sex, there are other areas where you’re going to have an advantage. That means your job isn’t only to try to rebuild the area that’s breaking down but also to preserve the areas that excel. But across the board, both genders lose competency in the areas in which they are weak to begin with. So women lose spatial cognition, and men suffer verbal losses. Though it’s certainly not true for everyone, it may give you clues as to what areas of your brain to concentrate on as you age – or it may help you play to your strengths. (Those with poor memory recall can use organizational skills to compensate, for example.)

You don’t have to have an elite brain to know that your three-pound organ has more power than a rocket booster. It controls everything from your emotions to your decision making, and it gives you the ability to understand why the baseball in Figure 11.1 is pretty damn funny. But when we discuss memory loss, we’re essentially focusing on three specific brain functions: sensory information (your ability to determine what information is important), short-term memory loss (quick, what’s the title of this chapter?), and long-term memory loss (that’s your bank of recipes, trivia, names, and every piece of information you’ve known, read and stored during your life).

Whether you’ve seen it on the news, on TV shows or within your own family, you know how dementia looks from the outside: people forget faces, names, where they live and information that seems – to the rest of the world – so easy to remember. The most frequently seen problem: getting lost on a walk home. To really control your own genetic destiny, you need to take a look at what memory loss looks like on the inside. For the record, age-related memory loss is classified in several ways. Conditions such as Alzheimer’s, dementia and mild cognitive impairment are all technically different. For our purposes, we’re tackling them all together as age-related memory problems because of the similarities in how they change people’s lives.

Your Brain: Mind and Matter

Before we crack some skulls and dive inside the brain, let’s quickly look at what memory really is: essentially, it’s the process of learning information, storing it and then having the ability to recall it when you need it – whether to solve problems, tell stories or save yourself on the witness stand.

Learning begins with those power connections in your brain: neurons firing messages to one another. Your ability to process information is determined by the junctions between those neurons, called the synapses. The ability of brain cells to speak to one another is strengthened or weakened as you use them. We’ll spare you all the biological miracles that take place between your ears, but essentially, the more you use those synapses, the stronger they get and the more they proliferate. That’s why you may have strong neural pathways for your family history or weak ones for 1980s music trivia. That also gives you a little insight into how you remember things. If something’s exciting to you, then you learn it faster – and train those synapses to make strong connections. But if the information seems more boring than the sexual habits of an earthworm, you can still learn and build those connections with repeated use.

FACTOID

Type 2 diabetes (the kind associated with being overweight) increases the risk of Alzheimer’s, probably by increasing inflammation or arterial ageing, but also because too much of the hormone insulin in the brain can stimulate beta-amyloid buildup. In fact, Alzheimer’s is now being called type 3 diabetes.

Problems arise when synapses lie dormant: the less you use certain connections, the greater chance they have of falling into disrepair (like losing fluency in a foreign language if you don’t use it for a long time). Technically, we actually learn by weakening underutilized synapses and repairing and strengthening the synapses we commonly use. So if you cook a lot and enjoy it, you’ll eventually know the recipes by heart – and learn them faster because it’s enjoyable. You build a large connecting wire, which allows for the faster flow of information. By contrast, lesser-used pathways fall into disrepair, so you lose or disable those connections. If you haven’t exercised your 1970s TV trivia synapse in a long time, then you’re not going to remember the name of the kid who played Bobby Brady on The Brady Bunch (ten points if you said Mike Lookinland before we did).

To keep your memory functioning at optimal power, you’ll need to focus on three aspects of your biology.

Your Brain. Let’s peel back your scalp and look through a peephole in your head. From the toupee’s-eye view, you can see that your brain has 100 billion nerve cells, and each cell receives one hundred messages per second. Yup. In the time it takes you to read this sentence, your brain cells have been doing more processing than the Inland Revenue’s computer server.

Your neurons – the cells that transmit information – look like mops with shaggy strings that reach out to one another, while the handles of the mops act like cables that carry the information. These neurons talk with one another with the frequency of eleven-year-old girls at a sleepover party; a lot of information is exchanged very quickly.

The hippocampus, which is shaped a little like a seahorse and is buried deep inside your brain (see Figure 1.1), is the main driver of memory. (The other two memory-related areas of the brain are the prefrontal cortex, which controls the executive function of your brain, and the cerebellum, which controls balance.) Your hippocampus processes information before it is stored. It works best when you’re either emotionally interested in the material or alert when you’re learning about it. That’s one reason why coffee may aid memory; it seems to increase your alertness the first time you learn something, which increases the chance you’ll deposit it in your long-term memory bank.

But for the purposes of ageing, we’re mostly concerned about what happens to the power lines within your brain. So flip on your hippocampus (or grab a cup of coffee) and remember this: there are protein fragments in your brain that sound like the name of a Star Wars droid – beta-amyloid – and they’re responsible for gunking up your power lines like overgrown vegetation or fallen branches. They’re probably responsible for causing Alzheimer’s. The primary defect in Alzheimer’s affects the input and output power lines of the hippocampus. Memory starts to fade. (The other physiological sign of Alzheimer’s is the buildup of what are called neurofibrillary tangles. They’re insoluble twisted fibres that build up inside neurons, like power lines getting crossed up and sending energy to the wrong location. These tangles influence intelligence.) Now, a downed branch here and there won’t do much to disrupt the flow of energy through your entire city, but what happens when a lot of branches or shrubs or trees fall on the same part of the grid? You’re out of commission.

Figure 1.1 Storage Units Memories are stored in the hippocampus. The other two major memory-related areas of the brain are the prefrontal cortex (controlling the executive function of your brain) and the cerebellum (used for balance). Craving memories are found in the insula.

In general, genes control how much beta-amyloid you have. Some branches may be knocking out those notes from your course in eighteenth-century Roman history, while others may be causing you to forget to pick up the very thing that you went to the supermarket for in the first place. But your genes don’t have complete control. You can alter the amount of gunk you have weighing down your power lines by altering the expression of one of your genes: the Apo E gene, to be exact. Apo E protein acts like the power company crew that removes the branches and sap from the power lines after the storm. It sweeps through and removes the beta-amyloid so that your synapses can keep functioning and you don’t lose the ability to remember what year Diane Keaton won an Oscar for best actress (1977). Whenever we create new synapses to help our brain improve itself, some of this beta-amyloid remains behind, and the Apo E workers clear the gunk to ensure a clean connection.

One group in the union, however, local Apo E4, sabotages the effort to restore power and even gunks up the power lines further (see Figure 1.2). Research shows that an elevated level of the E4 protein is correlated with a higher incidence of Alzheimer’s. Fortunately, there are things you can do to turn down the activity of the E4 gene and allow the rest of the Apo E team to clear your power lines. Eating turmeric, which is found in Indian foods, seems to reduce expression of the E4 gene (India, by the way, has a relatively low incidence of Alzheimer’s). Exercise has a similar effect.

Your Blood Supply: While there’s a strong genetic component to memory problems, we’d be remiss if we didn’t address the arterial component of an ageing brain. A lack of healthy blood flow to the brain is one of the other main causes of forgetfulness. Each side of the brain has a separate blood supply that looks like several large trees during winter. Between the twigs at the tips of the major branches are areas of brain that are dependent on blood from each of the surrounding trees. The area farthest from two blood-supply lines is the watershed area where we tend to have ministrokes when the branches of surrounding trees are pruned by atherosclerosis or the tree trunks themselves wither from poor maintenance (see Figure 1.3). Cholesterol-lowering statin drugs may help maintain memory by preserving tree architecture, while also reducing inflammation that ages the brain cells directly (more on arterial health in the next chapter).

Figure 1.2 Power Outage Apo E proteins that bind cholesterol are like workers clearing junk to ensure a good connection between neurons. Apo E4 gets in the way, and the power lines sag under a substance called beta-amyloid.

Figure 1.3 Delivery Failed When blood (and the nutrients it’s carrying) can’t get to the brain, tissues shrink – and you start to lose memories.

Brain Pills?

It’d be nice if there were such a thing as mental Viagra – just swallow a pill and get a little lift where you need it. But the verdict’s still out on many pills, supplements and vitamins that purport to make your memory stronger. Here’s our take on the ones that get most of the attention:

Pill

Do We Recommend It?

The Fine Print

Aspirin

Yes

Research shows a 40 percent decrease in arterial ageing, a major cause of memory loss, for those who take 162 milligrams of aspirin a day. Though science isn’t sure of the mechanism protecting against memory loss, it may happen because aspirin helps decrease that gunky beta-amyloid from your wiring, and because it improves circulation.

Vitamin E

In your diet, ideally

People who consume the highest amount of vitamin E are 43 percent less likely to get Alzheimer’s. You can get the vitamin E you need by eating just 3 ounces of nuts or seeds a day (about 15.5 milligrams), which is our preferred method. Alternatively, you can take a 400 IU (international unit) supplement daily if you take it with vitamin C and are not taking statin drugs like Lipitor.

Vitamins B6, B12, folic acid

Yes

Without B vitamins, your neurotransmitters don’t work efficiently. To compound matters, without B vitamins, your homocysteine levels rise, and that doubles the risk of developing Alzheimer’s. Homocysteine is an amino acid associated with stroke, heart disease and Alzheimer’s. Although no study has demonstrated a benefit of supplementation to your thinking process, the products are generally safe, and anecdotal evidence is enticing. We recommend a supplement with 400 micrograms of folic acid, 800 micrograms of B12 and 40 milligrams of B6 a day.

Aceytl-L-carnitine/ alpha-lipoic acid

Not yet

There are lots of strong theoretical reasons why this should enhance brain health – specifically, by improving mitochondrial activity and reducing mitochondrial DNA decay, resulting in higher neutrotransmitter function – but there’s not enough evidence in humans.

Rosemary, roses and mint

Yes

Not to ingest, but to smell. Research suggests that inhaling these three aromas at the time of learning a new task can enhance recall when you’re exposed to the scent at a later time.

Ginkgo biloba

If you want to

Though there are no large studies to support its use, there’s some promise that this very commonly used supplement is effective in helping improve cognition. It can also thin the blood, which can be helpful in people with blood vessel disease but dangerous for those with clotting disorders or anticipating surgery. Because it’s considered a safe antioxidant supplement, we’re comfortable with you trying 120 milligrams daily to see if it has any positive effects.

Huperzine A

Maybe

This ancient Chinese herb was used for memory loss even before we knew that it increases acetylcholine levels by blocking a chemical that devours this precious neurotransmitter. If you have mild cognitive impairment, we recommend 200 micrograms twice daily and suggest that your doctor help titrate the treatment if other pharmaceuticals with similar effects are being used.

Vinpocetine

No

There’s not enough evidence that this supplement from a periwinkle plant helps, and it can reduce your blood pressure too much, so we would rather wait for more clinical trials.

Phosphatidylserine

If you want to

About 70 percent of our cell membranes are made from this, and as we age, the level of phosphatidylserine drops, and the membranes become brittle. This supplement seems to strengthen cell membranes and the phospholipid sheathing around nerves, protecting the cables that transfer information from shorting out. Since risks are few, taking 200 milligrams daily is reasonable.

Coenzyme Q10

Yes, but for other reasons

This supplement has a beneficial effect in protecting against Parkinson’s disease (a neural disease that can be caused by trauma, as in the case of boxers, or through viruses and genetics). As a potent antioxidant, it may help prevent inflammatory damage to the brain, but this remains unproven. The ideal dose is 100 milligrams twice a day (some research says that 300 milligrams four times a day is even better for Parkinson’s). This is one supplement where more than 90 percent of what’s sold doesn’t contain the real thing, so look for products that have actually been shown repeatedly to have in the bottle what’s on the label. The website to check to see if it contains what’s on the label: www.consumerlab.com.

Your Neurochemicals: Nerve cells communicate with one another via neurotransmitters, chemicals that ferry information from neuron to neuron across the synapses between them. The most common neurotransmitter is called acetylcholine. When levels of this chemical fall, especially in the hippocampus (the part of the brain that controls our memory), we develop cognitive impairment. Many of the treatments for Alzheimer’s are aimed at increasing the amount of acetylcholine in the brain.

FACTOID

Those neurofibrillary tangles associated with Alzheimer’s disease contain aluminium (an element that makes up 14 percent of the earth’s crust). While there’s no evidence suggesting that aluminium causes memory problems, it’s better to try to avoid it. One way to reduce the aluminium you absorb: use sea salt instead of table salt, which is processed with aluminium to avoid caking. Other things that contain aluminium include nondairy creamers, antacids, cans, certain cookware and antiperspirants.

The other chemical that plays a significant role in memory is called brain-derived neurotrophic factor (BDNF, or just neurotrophins if you prefer), which works like Miracle-Gro for your brain. During infancy, BDNF helps develop nerves that help us learn, but as we get older, things like inflammation and stress can decrease its levels. Research shows that you can do things to improve your levels of BDNF, such as consuming the spice curcumin (a component of turmeric), restricting calories, doing exercise, being in love and taking some of a class of antidepressants known as selective serotonin reuptake inhibitors, or SSRIs. Not surprisingly, you can decrease BDNF by eating high levels of saturated fats and refined sugars, as well as by not getting enough of the natural antidepressant tryptophan (yes, it’s found in turkey, but there’s twice as much in spinach) in your diet.