Think Smart: A Neuroscientist's Prescription for Improving Your Brain's Performance (27 page)

According to neuroscientists at the University of Zurich, it’s possible to lift one’s mood via a seventy-second exercise consisting of nothing more complicated than listening to a musical selection while looking at what the experimenters call “happiness” pictures (a man holding his smiling baby or laughing children playing by the ocean).

For example, in the emotional induction method developed by neuroscientists at the University of Zurich, the third movement of Beethoven’s Sixth Symphony, when combined with a “happiness” picture, reliably lifts a person’s mood. In each instance, the subjects were simply told to look at the pictures, listen to the music, and mentally place themselves into the same mood. In all instances the mood changes occurred within seventy seconds. Most important, their emotional experiences were most powerful in response to the pictures and the music together rather than either the music alone or the pictures alone. Combining the music with the pictures also induced the strongest activation in a distributed emotional network plus parts of the frontal, temporal, and occipital lobes of the brain. When you do this exercise, select musical selections with pictures that you find emotionally appealing. After combining pictures and music enough times, you’ll find that you no longer need the pictures but can produce the same positive effect on your mood by mentally recreating the pictures in your imagination.

In another study on the effect of music on mood, carried out at the University of Pennsylvania, volunteers reported feeling happier after listening to selected music clips (a “jazzed-up” version of Bach’s Brandenburg Concerto Number 3, for instance). While in this state of heightened mood the subjects performed better on memory tests than did participants in the experiment who didn’t listen to mood-uplifting music. It’s speculated that this memory improvement results from a positive mood-induced increase in attention. But whatever the explanation, the results suggest that you can use music to simultaneously lift your mood and increase your memory.

Obviously, the musical selections will vary from one person to another.

Discover the particular musical selections that arouse in you positive emotions under different circumstances. Think about your iPod musical library in a completely different way. Why do I enjoy listening to Bach while home alone in the evening but enjoy Van Morrison while driving to work? By exploring questions like this you will discover the particular musical selections that arouse positive emotions under particular circumstances.

Although the UCLA study was a small one that enrolled only seventeen people, it has huge implications for brain enhancement. The brain, it’s turning out, is even more plastic and malleable than the most enthusiastic researchers have heretofore imagined. Perhaps enhancement doesn’t require months and even years of effort, but worthwhile alterations can be brought about in the brain in as short a time frame as two weeks (as occurred in the juggling study mentioned on page 241). Moreover, improvement doesn’t entail expensive or inconvenient measures: no spas, health clubs, or specially prepackaged meals.

Most important, a brain-enhancement program confers benefits that can be discerned on testing five years later, as shown in the ACTIVE (Advanced Cognitive Training for Independent and Vital Elderly) trial conducted by the National Institutes of Health discussed on page 221. This study also involved a short time frame of ten sessions lasting a little over an hour. In the NIH study, the emphasis was on improving memory, mental processing speed, and reasoning.

Given all this, how should we think about the brain? What metaphor is most appropriate? Historically, many metaphors have been suggested. One of the more recent ones emphasizes the similarity between the brain and a computer. And while it’s true that some of the brain’s functions can be likened to the operations of a computer, this metaphor breaks down when it comes to physical structure and natural life cycles. Computers don’t change in terms of their physical components; they continue to operate at maximal capacity until, at some unpredictable time in the future—and usually without warning, and under the most inconvenient circumstances—they abruptly cease to function. In many cases, after suitable fixes they can be restored to full function.

The brain, in contrast, changes in both size and function as it ages. The brain reaches its maximum size (measured by weight) somewhere between twenty and thirty years of age and decreases progressively for the remainder of its life span. Function too changes with age: as we age we experience decreases in reaction time, spatial processing, and working memory, among other functions. Yet these changes aren’t due so much to brain cell loss—as was formerly believed—but to failures to maintain the neuronal circuitry linking neurons to one another. In support of this view, neuroscientists have found that the number of synapses linking neurons to one another in the cerebral cortex decreases with age, while the number of neurons themselves doesn’t change very much.

Given these facts about the brain, the metaphor of brain-as-computer is of limited usefulness. What metaphor will enable us to put into practice all of the different pathways to brain enhancement and improvement suggested in this book?

The best and most helpful metaphor for the brain that I have come across was suggested by neurologist Kenneth Rockwood of Dalhousie University, Halifax, Nova Scotia, Canada. “Perhaps we should think of the metaphor of a series of marathons,” he says. “As our brains age, we must prepare them to resist injury—equip them with good education, train them thoughtfully with challenging regimens, support them with nurturing environments, and be prepared to refresh them from time to time.”

Rockwood’s metaphor allows for both the structural and functional changes that accompany brain growth, development, and aging, as well as the active approach that will enable us to help our brain to achieve optimal performance throughout our lives. The metaphor also is consistent with the brain’s varying performance depending upon its physical conditioning, which can always be improved by additional effort and training.

Rockwood concludes: “We should recognize that performance can vary dramatically from one marathon to the next. Perhaps the most important consequences of such a metaphor are that we should aim to see cognitive aging as a challenge for which we must prepare, that we gain enough equanimity to accept the slowing that even elite athletes experience, and that we reflect on what has been achieved along the way.”