WHAT’S THAT WORD AGAIN?At the ancient Greek town of Delphi, an oracle—a woman chosen for her purity—sat atop a tripod next to a hole in the ground. According to legend, the god Apollo had earlier tossed the body of the monstrous serpent Python into that very opening. Gases from the decomposing body rose to the surface and met the nose of the Delphic oracle. She inhaled and fell into a trance in which Apollo spoke to her. The oracle shared her revelations, prophesying to the people. But she did so in an unintelligible tongue. Thus, the oracle at Delphi knew great truths, but could not communicate them in plain language. Priests of the temple came to her rescue, translating the oracle’s gibberish for the people.
A modern-day, medical parallel to the oracle’s problem can be found in a rare disease called Wernicke’s aphasia. It strikes the nerve fibers in a particular part of the posterior temporal lobe. People with this disorder lose their ability to understand language and speak intelligibly. Their words often come out with apparently good syntax, but they make no sense. A so-called “word salad” of a patient with Wernicke’s aphasia might sound like this: “Fly to the oven and get the government mystery. Repeat the library, fourteen alphabet monster.”
WHAT’S THAT WORD AGAIN?The conditions of the oracle and a patient with Wernicke’s aphasia lie at the extreme end of a scale of language-processing difficulties. At the lower end lies the occasional problem of searching for, but not finding, the right word to say. Somewhere between the two is the paradox of the aging brain’s skill with language. If a brain stays active and builds vocabulary, it may have a far richer treasure trove of words from which to choose than a much younger brain. But an aging brain struggles more to find the words it wants. Wise elders sometimes wrestle with the maddening problem of knowing what they want to say, but being unable to retrieve the correct words from memory—and the problem typically increases with age.
Scientists call this problem the “tip of the tongue” experience, which occurs when a word exists in a person’s lexicon but temporarily remains inaccessible to the brain. It’s a normal part of aging—tip-of-the-tongue problems typically begin around age 40—and is reported as one of the most frequent and troubling problems of older adults. As brains mature into middle age and beyond, they think more deliberately, and for a longer time, before making decisions. They may know the answer to a question, but fail to come up with it quickly.
Research associate Meredith Shafto of Britain’s University of Cambridge studies normal cognitive aging. She told the Washington Post that tip-of-the-tongue experiences are “part of what we call normal or healthy aging … With normal aging there are changes that are noticeable and distressing and irritating, but they are not pathological.”
WHERE IT ALL HAPPENSA research team led by the Pomona College Project on Cognition and Aging, and headed by Deborah Burke, discovered that tip-of-the-tongue experiences increase as the density of neurons in a brain region called the left insula decreases. The insula, deep between the frontal and temporal lobes, recently has drawn neurologists’ attention for a variety of reasons. It has been linked to neural processing of sound. It lights up in brain scans when the body feels or anticipates pain, empathizes with others, desires a drug, or responds to jokes or music.
Burke’s team relates the insula’s age-related decline in gray matter to a theory equating atrophy with disuse: Neural connections that encode words grow weak and decline if those words aren’t often spoken aloud. Those neural connections are scattered around the brain, but the insula may be a key performer in the networks’ reconstruction of words.
“We like to think of words as being stored in a unit in our head, and that we have a little place in our minds where we have [for example] Brad Pitt, and we know what he looks like and what movies he’s been in and his name and all that,” she told the Washington Post. But word-related information isn’t stored in such an integrated way. Various neural circuits encode how a word sounds, what it means, how it fits into the syntax of language, how it’s associated with images, and so on. The brain can lose access to one part of the related circuits and not the others.
BRAIN INSIGHT
Verbal fluency reaches a peak in people who speak dozens of languages
Bilingual people speak two languages. Trilingual people speak three. Those fluent in four or more are polyglots, Greek for “many tongues.”
The most famous polyglot in the United States was probably Thomas Jefferson. He fluently spoke and read English, Greek, Latin, French, Italian, and Spanish. Jefferson also attempted German and dabbled in Arabic, Gaelic, and Welsh.
Other notable polyglots included Heinrich Schliemann, excavator of the ancient city of Troy, who spoke German and at least 12 other languages, and Jean-François Champollion, who spoke more than a dozen languages by age 20, and went on to crack the puzzling hieroglyphs of the fabled Rosetta stone.
One of the most amazing polyglots was German diplomat Emil Krebs. By the time he entered Berlin’s Foreign Office school for interpreters, he already spoke a dozen languages. He insisted on learning the toughest ones, which led him to Mandarin. In a few years, he was sent to China as Germany’s chief interpreter. The empress dowager took tea with him to enjoy hearing him speak. By his death in 1930, Krebs had learned at least 65 languages, including Armenian, which he grasped in nine weeks. Postmortem examinations of his brain revealed unusual cellular organization in Broca’s area, a region associated with speech.
The circuits for word sounds and objects appear to be particularly vulnerable to decay because there seldom is a logical connection, except for onomatopoeic words such as bang and splat, which take their names from their sounds. Why is a rose called a rose?
As a result of this disconnect between a word and the thing it represents, you might recognize Brad Pitt in a magazine photograph but not recall his name. Your brain’s connection to the network containing his name deteriorates. This happens when the circuits lie dormant for too long, and leads to so-called “transmission deficits.” If you don’t hear the name Brad Pitt while looking at his face, the connection can wither.
Sounds are more vulnerable to decay than other kinds of experiences, Burke said. That would explain why you can know a word, and know you know it, but struggle with the tip-of-the-tongue experience to retrieve it.
PRIMING THE PUMPBurke and other researchers discovered that the recall of tip-of-the-tongue words increased with “phonological priming.” That’s a fancy way of saying that when a person struggling to come up with a word on the tip of the tongue experiences other words containing similar sound—especially the initial sound, number of syllables, and stress patterns of the hidden word—the desired word often comes to mind. For example, aiming at the target word Velcro, Burke’s team supplied to test subjects the words venerable, pellet, decreed, overthrow, and mistletoe. For the target word Columbus, Burke’s team supplied the words cologne, conniver, alumnus, omnibus, and amoebas. Reading and saying aloud those words brought success. “It has been suggested that a [tip-of-the-tongue] target word pops into mind ‘spontaneously’ when phonological components of the word occur inadvertently during conversation,” Burke’s team wrote. Perhaps trying to think of words similar to the missing one will help, especially if the word’s initial sound can be recalled. If you’re stuck in a tip-of-the-tongue moment, Burke recommends focusing on words that spring into your mind as you search for the missing target. Their related sounds may prime the pump and restore connection to the lost word or phrase.
The Pomona College Project on Cognition and Aging’s research on the insula and tip-of-the-tongue problems predicts that keeping neural connections strong for a broad vocabulary will reduce failures to find a particular word. “Using language in ordinary activities like socializing or in games like Scrabble may help keep words accessible and off the tip of the tongue,” the project’s team wrote. Reading aloud and talking to people at dinner may help maintain the neural circuits associated with words and sounds.
There isn’t much you can do for retrieving names from your past, but you can increase the strength of encoding for current acquaintances. That’s a memory-enhancing skill discussed in Chapter 7.
FINDING THE RIGHT WORDSTip-of-the-tongue problems form a subset of verbal fluency studies. Verbal fluency is the ability to quickly and smoothly access vocabulary when writing or speaking. It typically declines with age, and also can be affected by developmental disabilities, brain injuries, cancer, and some neurological disorders. It is not a strong measure of intelligence, as some smart people do poorly on verbal fluency tests.
Tests of verbal fluency sometimes are used as indicators of possible cognitive impairment, as they may reflect changes in the brain’s word-processing centers. In a typical test, doctors might give a patient 60 seconds to list as many words as possible that start with the letter “P.” The test taker counts and analyzes the words, as some might not fit the criteria. The 1996 movie Phenomenon depicts a verbal fluency test. In one scene, a doctor asks an ordinary man whose cognitive functions have been enhanced to name as many mammals as he can in 60 seconds. The test subject responds by instantly reeling off 26 mammals in alphabetical order from aardvark to zebra.
BRAIN INSIGHT
Congresswoman Gabrielle Giffords shows just how resilient the brain can be
I pledge allegiance … to the flag …” By leading the pledge at the 2012 Democratic National Convention, former Arizona Congresswoman Gabrielle “Gabby” Giffords demonstrated how far she had come. And how far she still has to go.
Giffords was shot through the left side of her brain in January 2011. Details of her injuries have never been made public. However, the left hemisphere controls speech and right-side body movement. Giffords suffered impaired mobility and aphasia, the inability to speak.
Music therapy helped her talk again. While the left side of the brain controls language, both hemispheres process music. In an amazing feat of neuroplasticity, Giffords’ singing therapy helped her brain move her speech functions to the right hemisphere. She still slurred a few words and walked stiffly at the convention, but her achievement touched many viewers.
Traumatic brain injury can strike anyone. But you can do two things to reduce your risk. One is to protect your head with a helmet when riding a bike or motorcycle, or engaging in rough sports. The other is to build up your cognitive reserve to make your brain more richly connected and to increase its plasticity, should it ever be needed.
The subject of Phenomenon achieved greater verbal fluency via a terminal brain tumor that created new neural pathways. Not a pleasant option for cognitive enhancement, to say the least. More practical methods of improving verbal fluency, and cognitive strength in general, focus on general health. Sleep deprivation can decrease verbal fluency, as can a poor diet. Studies have shown that skipping breakfast, for example, can hurt verbal fluency, apparently by depriving the brain of its optimal nutritional needs. On the other hand, obesity has been linked to lowered verbal fluency and other cognitive functions. In particular, a 2010 study of more than 8,000 postmenopausal women using data from the Women’s Health Initiative, a major national U.S. health study, found that as a person’s body mass index rose, cognitive functions tended to decline. The group performing the worst on tests of verbal fluency and other cognitive tasks had a high ratio of hip circumference to waist size, meaning they carried excess weight on their hips.
If you want to improve your verbal fluency, try exposing your brain to new vocabulary words as well as new ways of putting them together. With practice, words become more familiar and you are more apt to easily retrieve them. If you read only the business section of the paper, you’ll know plenty of business-related words, but you’ll be less fluent in other lexicons. So try reading the editorial page or the sports section. If you’re reading online or on a handheld digital device, you can easily look up unfamiliar words. If you go to the trouble of mastering new words by processing and understanding them in context, you’ll strengthen verbal fluency.
An individual’s cognitive resources dramatically affect the ability to recall spoken and written words. As older adults usually have less working memory than their younger counterparts, it makes sense that they must make greater demands on their working memory to process language as they grow older. Studies in the 1990s demonstrated that older adults have good comprehension when they hear simple, short sentences spoken aloud because they don’t tax the working memory as much as longer, more complex ones. But in controlled experiments, older adults showed more difficulty in language processing than younger adults as sentences sprouted more clauses and phrases. The difference appears both in accurate recall of the words themselves as well as comprehension of their meaning. Too much information, delivered too quickly, can overload an elderly brain.
On the other hand, the brains of older adults work with nearly youthful efficiency when processing communications such as spoken conversations and instructions that are delivered in short, simple bursts. The decline in processing of language is not as big a problem for text on a page for obvious reasons: If the reader misses something on the first pass, he or she can back up and reread the difficult passage—at a slower pace, if necessary.
Memory for spoken words has been shown to be stronger in mature adults if they had musical training before the age of 12. A 1998 study at Chinese University in Hong Kong revealed that adults who learned how to play a musical instrument as a child scored 16 percent higher on tests for word memory than those who had no such training. The sample was small—a total of 60 college students—but the results nevertheless were intriguing. Thirty students who had at least six years of musical training before they turned 12 demonstrated better recall of words read aloud from a list than a group of 30 who lacked comparable musical training. The memory enhancement did not extend to visual designs, which usually are processed in the brain’s right hemisphere. The musically trained students had no advantages at remembering and drawing simple designs they saw.
Neural plasticity apparently explains the Hong Kong study’s results. Brain scans of professional musicians have noted an expanded region of neurons in the left planum temporale, a roughly triangular region of the temporal lobe. The region plays a role in processing not only music but also verbal memory. The research supports other work suggesting that musical training prepares the brain for more than just music. Learning to read and play music requires the brain to rapidly recognize and process groups of symbols. Enhanced sensitivity to grouping of symbols likely transfers to the symbols of letters, standing for sounds, that join to form words.
PARLEZ-VOUSDecades ago, some scientists believed that learning a second language caused linguistic confusion or even cognitive deficits in young children. Instead, the brains of bilinguals, as children and adults, tend to have a stronger executive function than those of people who speak only one language. The executive function, centered in the prefrontal cortex, keeps the brain focused on what’s important. It supports the ability to hold two things in the mind and switch back and forth as needed, such as conversing while following a game on television. Or it can tune out distractions to focus concentration. Children who learn a second language generally are better able than their one-language counterparts to maintain attention while being bombarded with irrelevant stimulation.
“If you have two languages and you use them regularly,” cognitive neuroscientist Ellen Bialystok of York University in Toronto told the New York Times, “the way the brain’s networks work is that every time you speak, both languages pop up and the executive control system has to sort through everything and attend to what’s relevant in the moment. Therefore, the bilinguals use that system more, and it’s that regular use that makes that system more efficient.”
BRAIN INSIGHT
Telepathic Tweeting
Your thoughts in 140 characters or fewer
In early April 2009, University of Wisconsin biomedical doctoral student Adam Wilson prepared to send the first message that could be described as telepathic.
Wired magazine likened the event to the moment when Alexander Graham Bell, inventor of the telephone, sent his assistant what Bell said was the first phone message: “Mr. Watson, come here. I want to see you.”
Wilson’s message was more a simple announcement of what he was doing, and could be seen by anyone with access to the Internet: “USING EEG TO SEND TWEET.”
Wilson manipulated a computer program that recognized changes in his brain activity patterns when he concentrated on particular letters of the alphabet. His thoughts moved a cursor and selected letters to be posted to his microblogging Twitter account. The interface emerged from a software tool developed by Justin Williams of the University of Wisconsin’s Neural Interface Technology Research and Optimization Lab and Gerwin Schalk, a neural injury specialist at the Wadsworth Center, a public health laboratory in upstate New York.
Medical uses being explored for this program include opening avenues of communication with patients who have “locked-in” syndrome and cannot move or speak. Wilson’s subsequent brain-to-computer messages indicated other applications. “GO BADGERS,” tweeted the University of Wisconsin football fan.
That’s important for success as teens and adults. Barbara Lust, a developmental psychology and linguistics expert at the Cornell Language Acquisition Lab, says a strong executive function is “responsible for selective and conscious cognitive processes to achieve goals in the face of distraction.” Those goals include academic readiness and success, both as children and later as adults.
Enhanced cognition for bilinguals extends into old age. Bialystok found that bilingual elderly adults outperform monolinguals on tasks that test executive function. Furthermore, after studying the records of 400 patients with Alzheimer’s, she found that bilingual people exhibited symptoms of the disease an average of five to six years later than monolingual people. These findings appear to support a study of the nuns of Mankato, Minnesota, that suggested correlations between higher levels of education early in life, as well as expanded cognitive reserves of an enriched brain, with maintenance of cognitive functions, sometimes despite physical evidence of the initial stages of Alzheimer’s.
START EARLYAlthough humans can add a second language at any time, the best and easiest time to learn is early childhood. Young children who learn two languages at the same time don’t have the adult disadvantage of their primary language interfering with their acquisition of new sounds, grammar, and meaning. “When you’re a kid, all you’re working at is acquiring a language, and you don’t have anything to get in the way of that,” Lisa Davidson, an associate professor of linguistics at New York University, told Forbes. “When you’re an adult and you already have a language, the one you already know filters sounds and you get substantial interference from it.”
Immersion of a child in an environment where two languages are spoken all the time smooths the path to bilingualism. Hearing multiple speakers controls against acquiring an accent that is particular to one person. The sooner a child learns a second language, the more likely the child will master the accents and tones of a native speaker.
The Cornell Language Acquisition Lab recommends the following to help a child learn a second language:
Surround the child with conversations and social settings that expose him or her to the extra language.
If the child is learning a second language outside the home, keep the heritage language of the child’s family at home.
Give the child opportunities to play with children who speak the second language.
Read and tell stories in both languages.
Share music, film, and other fun language-learning environments in both languages.
Young people and adults have different aptitudes for learning a nonnative language, just as they have aptitudes for math or geography. Experts agree that the best way to master a second language varies with the individual. But in general, learning a second language gets harder with age.
To find their best learning method, adults might try audio or audiovisual programs, classes, conversations with native speakers, or immersion in the second language. When they find what works, they should stick with it. The key is to work a bit every day on acquiring the new language, and then expand vocabulary and sophistication. After achieving fluency, challenging the brain further might involve going to a higher level of instruction, such as taking a history or political science class in the second language. 
