Amputees sometimes experience phantom limb sensations, feeling pain, itching or other impulses coming from limbs that no longer exist. Neuroscientist V.S. Ramachandran worked with patients who had so-called phantom limbs, including Tom, a man who’d lost one of his arms.
The neuroscientist discovered that if he stroked Tom’s face, Tom felt his missing fingers were also being touched. Each part of the body is represented by a different region of the somatosensory cortex, and, as it happens, the region for the hand is adjacent to the region for the face.
Ramachandran deduced that a remarkable change had taken place in Tom’s somatosensory cortex: because Tom’s cortex was no longer getting input from his missing hand, the region processing sensation from his face had slowly taken over the hand’s territory. So touching Tom’s face produced sensation in his nonexistent fingers.
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This kind of rewiring is an example of neuroplasticity, the adult brain’s ability to change and remold itself. Scientists are finding that the adult brain is far more malleable than they once thought. Our behavior and environment can cause substantial rewiring of the brain or a reorganization of its functions and where they are located. Some believe that our thought patterns alone can be enough to reshape the brain.
Researchers now know that neurogenesis (the birth of new neurons) is a normal feature of the adult brain. Studies have shown that one of the most active regions for neurogenesis is the hippocampus, a structure vitally important to learning and long-term memory. Neurogenesis also takes place in the olfactory bulb, which is involved in processing smells.
But not all the neurons that are born survive; in fact, most of them die. To stay alive, the new cells need nutrients and connections with other neurons that are already thriving. Scientists are currently identifying the factors that affect the rate of neurogenesis and the survival of new cells.
Let’s take a look at six things that may help boost neuron growth and brain health.
1: Exercise
Studies have revealed that exercise can improve the human brain’s executive functions (planning, organizing, multitasking, and more). Plus, exercise is well known for its mood-boosting effects, and people who exercise are less likely to get dementia as they age.
Athletic senior citizens have better executive function than do those who are sedentary; even seniors who have spent their entire lives on the couch can improve these abilities just by starting to move more in their golden years.
And, thankfully, you don’t need to be Chuck Norris to get the brain benefits of exercise. Studies of senior citizens suggest that as little as 20 minutes of walking a day can do the trick.
A variety of mechanisms might be responsible for this brain boost. Exercise increases blood flow to the brain, which also increases the delivery of oxygen, fuel and nutrients to those hard-working neurons. Research has shown that exercise can increase levels of a substance called brain-derived neurotrophic factor (BDNF), which encourages growth, communication and survival of neurons.
Exercise also improves sleep quality, several studies suggests. And immune function. Is there anything it can’t do?
2: Diet
The brain needs fuel just as the body does. So what will really boost your brainpower, and what will make you lose your mind?
Saturated fat, that familiar culprit, is no better for the brain than it is for the body. Rats fed diets high in saturated fat underperformed on tests of learning and memory, and humans who live on such diets seem to be at increased risk for dementia.
Not all fat is bad news, however. The brain is mostly fat—all those cell membranes and myelin coverings require fatty acids. So it’s important to eat certain fats, particularly omega-3 fats, which are found in fish, nuts and seeds. Alzheimer’s disease, depression, schizophrenia and other disorders may be associated with low levels of omega-3 fatty acids.
Populations that traditionally eat diets high in omega- 3 fatty acids tend to have lower rates of disorders of the central nervous system.
It’s especially important that babies get enough fat. Babies who don’t get enough of the stuff have trouble creating the fatty myelin insulation that helps neurons transmit signals. Luckily for babies, breast milk is 50 percent fat.
Some of the best brain foods include walnuts, blueberries and spinach. Fruits and vegetables in general appear to be brain superfoods. Produce is high in substances called antioxidants, which counteract atoms that can damage brain cells. Researchers have found that in aging rats high-antioxidant diets keep learning and memory sharp and even reduce the brain damage caused by strokes.
It’s not just what you eat that affects the brain. It’s also how much. Research has shown that laboratory animals fed calorie-restricted diets—anywhere from 25 to 50 percent less than normal—live longer than other animals do. And it turns out they also have improved brain function, performing better on tests of memory and coordination. Rodents on calorie-restricted diets are also better able to resist the damage that accompanies Alzheimer’s, Parkinson’s and Huntington’s disease.
3: Stimulants
Stimulants are substances that rev up the nervous system, increasing heart rate, blood pressure, energy, breathing and more. Caffeine is probably the most famous of the group. (It’s actually the most widely used “drug” in the world.) By activating the central nervous system, caffeine boosts arousal and alertness. In high doses, though, this stimulation can go too far, causing jitters, anxiety and insomnia.
Although high doses of caffeine can undoubtedly have unpleasant effects (ranging from irritability to the most unpleasant of all: death in rare cases), small to moderate amounts can boost our mental functioning in ways researchers are now measuring.
One study showed that the equivalent of two cups of coffee can boost short-term memory and reaction time. Functional MRI scans taken during the study also revealed that volunteers who had been given caffeine had increased activity in the brain regions involving attention. In addition, research suggests caffeine can protect against age-related memory decline in older women.
4: Video Games
Video games could save your life. No, really. Surgeons who spend at least a few hours a week playing video games make one-third fewer errors in the operating room than nongaming doctors do. Indeed, research has shown that video games can improve mental dexterity, while boosting hand-eye coordination, depth perception and pattern recognition.
Gamers also have better-than-average attention spans and information-processing. When nongamers spend just a week playing video games, their visual-perception skills improve. And forget your notions of gamers as outcasts: one researcher found that white-collar professionals who play video games are more confident and social.
Video games activate the brain’s reward circuits. But according to one study, they do so much more in men than in women. Researchers hooked men and women up to functional MRI machines while the participants played a video game designed for the study. Both groups performed well, but the men showed more activity in the limbic system, which is associated with reward processing.
What’s more, the men showed greater connectivity between the structures that make up the reward circuit, and the better this connection was in a particular player, the better he performed.
There was no such correlation in women. Indeed, men are more than twice as likely as women are to say they feel addicted to video games.
Of course, we can’t talk about the effects of video games without mentioning the popular theory that they’re responsible for increasing real-world violence. A number of studies have reinforced this link. Young men who play a lot of violent video games have brains that are less responsive to graphic images, suggesting that these gamers have become desensitized to such depictions. Another study revealed that gamers had patterns of brain activity consistent with aggression while playing first-person shooter games.
But this doesn’t necessarily mean these players will actually be violent in real life. The connections are worth exploring, but so far the data don’t support the idea that the rise of video games is responsible for increased youth violence.
5: Music
When you turn on your favorite tunes, your auditory cortex analyzes the many components of the music: volume, pitch, timbre, melody and rhythm. But there’s more to this interaction than just the raw sound. Music can also activate your brain’s reward centers and depress activity in the amygdala, reducing fear and other negative emotions.
A highly publicized study suggested that listening to Mozart could boost cognitive performance, and inspired parents everywhere to start playing classical music for their children. But while the idea of a so-called “Mozart effect” remains popular, the original study has since been somewhat discredited, and any intellectual boost that comes from listening to music seems to be both tiny and temporary.
Still, music can treat anxiety and insomnia, lower blood pressure, soothe patients with dementia, and help premature babies to gain weight and leave the hospital sooner.
And music training can bolster the brain. The motor cortex, cerebellum and corpus callosum (which connects the brain’s two hemispheres) are all bigger in musicians than in nonmusicians. And string players have more of their sensory cortices devoted to their fingers than do those who don’t play the instruments. Though there’s no agreement yet on whether musical training makes you smarter, some studies have indeed shown that music lessons can improve the spatial abilities of young kids.
Music lessons and practice during childhood increase the sensitivity of the brain stem to the sounds of human speech. According to a recent study, the brain stem is involved in very basic encoding of sound, and lots of exposure to music can help fine-tune this system, even in kids without particular musical gifts.
So buck up, tone-deaf children of the world! Think of it like eating vegetables: chewing on that clarinet is good for you.
By the way, humans aren’t the only ones who benefit. Playing classical and soothing music can increase the milk yield of dairy cows! Weird, huh?
6: Meditation
Forget apples. If the scientific studies are to be believed, then an om a day is what really keeps the doctor away.
Meditation, or the turning of the mind inward for contemplation and relaxation, can increase focus and attention, improving performance on cognitive tasks. It can increase the thickness of the cerebral cortex, particularly in regions associated with attention and sensation. The growth doesn’t seem to result from the cortex growing new neurons, however—instead it appears the neurons already there make more connections, the number of support cells increases, and blood vessels in that area get bigger.
In addition to helping with anxiety disorders, it can be used to reduce pain and treat high blood pressure, asthma, insomnia, diabetes, depression and even skin conditions. And regular meditators say they feel more at ease and more creative than nonmeditators do.
Using brain-imaging machines, researchers are now illuminating the actual brain changes caused by meditation. They’ve discovered that, although the brain’s cells typically fire at different times, during meditation they fire in synchrony.
Expert meditators also show spikes of brain activity in the left prefrontal cortex, an area of the brain generally associated with positive emotions. And those who had the most activity in this area during meditation also had big boosts in immune system functioning.
In one study, researchers spent three months training volunteers in the practice of Vipassana meditation, which centers on minimizing distractions.
Then the volunteers were asked to perform a task in which they had to pick a few numbers out of a stream of letters. After having undergone meditation training, they were much better at identifying numbers that briefly flashed onto a computer screen. They also seemed to be able to do this without exerting as much mental energy.
So there you have it: six ways to boost your brain power. Regular exercise, especially as you age; a diet complete with omega-3 fats and antioxidants; mild stimulants like caffeine; stimulating video games; music and music training; and practicing meditation.
Reference: Six Ways to Boost Brainpower. Emily Anthes in Scientific American Mind Vol. 20, No. 1, 56-63; February 2009. doi:10.1038/scientificamericanmind0209-56
