‘Smarter: The New Science of Building Brain Power’ by Dan Hurley (Hudson Street Press; December 26, 2013)
Table of Contents:
i. Introduction/Synopsis
PART I: AN INTRODUCTION TO INTELLIGENCE, AND THE BIRTH OF THE NEW SCIENCE OF BUILDING BRAIN POWER
Section 1. An Introduction to Intelligence
1. Just What Is Intelligence, Anyway?
a. Crystallized Intelligence and Fluid Intelligence
b. What Is Intelligence Designed for?
2. On the Improvability (and Unimprovability) of Intelligence
Section 2. Attacking the Unimprovable Intelligence Paradigm: From Neural Plasticity to Improving Intelligence through Working-Memory Exercises
3. Michael Merzenich and Neural Plasticity
4. Improving Attention Span and Fluid Intelligence in Subjects with ADHD: Torkel Klingberg’s Landmark Experiment
a. An Introduction to Klinberg’s Experiment
b. Working Memory
c. Klingberg’s Experiment
PART II: THE RISE OF THE BRAIN-TRAINING INDUSTRY
5. The Brain-Training Industry
a. Cogmed
b. LearningRx
c. Posit Science
d. Brain Age and Lumosity
PART III: THE SCIENCE OF BRAIN-TRAINING
6. The Dual N-Back Experiment: Susanne Jaeggi and Martin Buschkuehl
a. An Introduction to Jaeggi and Buschkuehl’s Dual N-Back Experiment
b. The N-Back Task, and the Dual N-Back Task
c. The Results of Jaeggi and Buschkuehl’s Experiment
7. The Response to Jaeggi and Buschkuehl’s Experiment
8. The Science behind Commercially-Available Brain-Training Programs
a. Cogmed
b. LearningRx
c. Posit Science
d. Brain Age and Lumosity
PART IV: THE SCIENCE BEHIND OTHER BRAIN-BOOSTING INTERVENTIONS
Section 3. Mental Exercise: Learning a Musical Instrument or a Second Language, and Meditating
9. Music
a. Baby Mozart
b. Learning a Musical Instrument
10. Learning a Second Language
11. Meditation
Section 4. Physical Exercise
12. Exercise
a. Aerobic Activity
b. Resistance Training
Section 5. The Easy Routes to Building Brain Power: Diet, Pharmaceuticals, and Transcranial Direct-Current Stimulation (tDCS)
13. Diet
14. Pills
15. tDCS
PART V: HURLEY’S BRAIN-TRAINING PROGRAM, AND CONCLUSION
16. Hurley’s Brain-Training Program
17. Conclusion
i. Introduction/Synopsis
The idea that we can boost our brain power through interventions of various kinds has been around a long time. Over the years, numerous drugs, diets and other practices (including everything from physical exercise to learning a new language or musical instrument to meditation to even zapping the brain with electrodes) have been purported to pump up our mental strength. And lately, a new practice has been added to this list: brain-training games and exercises. Indeed, in the past decade a whole new industry has emerged around brain-training programs. Built on the premise that specific types of mental activities can strengthen our cognitive skills and add to general intelligence, companies such as Lumosity and LearningRx have convinced millions of paying customers that their product will give them an edge in the brains department.
The more skeptical among us, however, may find ourselves wondering just what is the scientific basis behind all these brain games and other interventions. It was just this thought that occurred to science writer Dan Hurley; and so, following his skeptical sense, Hurley decided to investigate the matter for himself. What Hurley found was a scientific field that, though young, is bustling with activity (and controversy).
The new science of building brain power may be said to have truly kicked off in 2002. In that year, Swedish psychologist Torkel Klingberg performed a study wherein he found that subjects diagnosed with ADHD improved in both attention span and general intelligence after undergoing a brain-training program that involved working-memory exercises (it was this very study that kick-started the brain training industry).
The finding flew in the face of the long-accepted belief that intelligence simply could not be enhanced through training; and therefore, it sparked a great deal of interest in the scientific community. Eager to test the new finding, scientists from all over the world launched their own studies. While not all of the studies replicated the results that Klingberg found, many did; and enough promising results were found to draw even more interest into the field (while those who found negative results began setting up a staunch opposition to the research).
Despite the minority opposition, the long-held belief in immovable intelligence was rocked, and scientists began testing other kinds of interventions as well (including all of those mentioned above). While many of the interventions tested were found to have no effect on cognitive functioning, some did, and thus the new field gained even more momentum.
Wanting very much to get to the bottom of the matter (and the controversy) Hurley decided to check out the studies himself, and also to interview the major researchers in the field (on both sides of the debate). Based on this investigation (which is explored at length in the book), Hurley launched his own brain-training experiment–on himself. Specifically, Hurley took all of those interventions which he felt had the best evidence behind them and incorporated them into a grand brain-training program to see whether he could improve his intelligence.
The routine included the following: A boot camp program (that incorporated both aerobic exercise and resistance training); Lumosity; learning a new musical instrument (the lute); mindfulness meditation; a nicotine patch; coffee; and transcranial direct-current stimulation (tDCS). The results of the experiment? They were mixed.
What follows is a full executive summary of Smarter: The New Science of Building Brain Power by Dan Hurley.
PART I: AN INTRODUCTION TO INTELLIGENCE, AND THE BIRTH OF THE NEW SCIENCE OF BUILDING BRAIN POWER
Section 1. An Introduction to Intelligence
1. Just What Is Intelligence, Anyway?
a. Crystallized Intelligence and Fluid Intelligence
Before we launch into an investigation of the new science of building brain power, we must first come to an understanding of just what brain power, or intelligence, truly is.
Let us begin with the IQ test, as this is the most famous indicator of intelligence. What is important to note is that the IQ test actually measures two general varieties of intelligence: crystallized intelligence and fluid, or general, intelligence.
Crystallized intelligence includes your general store of knowledge, which (hopefully) increases over time. As Hurley explains, “standard IQ tests include measurements of crystallized intelligence, your treasure trove of stored-up information and how-to knowledge, which just keeps growing as you age—the sort of thing tested on Jeopardy! or put to use when you ride a bicycle” (loc. 216).
Fluid intelligence, on the other hand, is less about what you know and more about how you think. It includes abilities like problem solving, recognizing patterns and manipulating information in your mind. As the author explains, “fluid intelligence… is the underlying ability to learn, the capacity to solve novel problems, see underlying patterns, and figure out things that were never explicitly taught” (loc. 216).
When it comes to measuring crystallized intelligence in isolation, this is relatively straightforward, as this simply requires testing general knowledge. Fluid intelligence, on the other hand, would seem to be quite a bit more complicated to measure, as it involves several seemingly disparate skills. Still, scientists have managed to design a number of tests that are quite good at measuring fluid intelligence, with one test in particular standing above the rest: the Raven’s test (loc. 358).
Each question in the Raven’s test follows the same general pattern: you are presented with a 3 x 3 matrix with each square occupied by a symbol (except 1 of the squares). Your task is to read the pattern that emerges from the 8 symbols, and use it to infer what symbol belongs in the empty square (out of 6 multiple-choice options). In addition, the patterns become more and more difficult to decipher as the test proceeds. As Hurley explains, “anyone who has taken an intelligence test has seen matrices like those used in the Raven’s. Picture three rows, with three graphic items on each row, made up of squares, circles, dots and other symbols. Do the squares get larger as they move from left to right? Do the circles inside the squares become filled in, from white to gray to black, as they go downward? One of the nine items is missing from the matrix, and your task is to discern the underlying patterns—up, down, across—in order to select the correct item from one of six possible choices. While at first the solutions are obvious to most people, they get progressively harder, reaching the point where, by the end of the test, they baffle all but the brainiest” (loc. 358). (You can check out sample questions, and even take the Raven’s test here: http://www.intershop.it/testqi/testqi1/iqtest2.htm.)
Just why the Raven’s test is such an accurate measure of fluid intelligence may not be clear at first. But the fact is that the questions require pattern-recognition, logic, and problem-solving—all of which are very much at the heart of what fluid intelligence is. Hurley puts it this way: “why matrices should be considered the gold standard of fluid-intelligence tests may not be obvious. But consider how central pattern recognition is to success in life. If you’re going to find buried treasure in baseball statistics, permitting your team to win games by hiring players unappreciated by other teams, you’d better be good at matrices. If you want to find cycles in the stock market to exploit for profit; if you want to find the underlying judicial reasoning behind ten cases you’re studying for law school—for that matter, if you need to suss out a woolly mammoth’s nature in order to trap, kill, and eat it—you’re essentially using the same cognitive skills tested by matrices” (loc. 365).
b. What Is Intelligence Designed for?
Importantly, this quote sheds light not only on what fluid intelligence is, but what it was designed for (by evolution), and also what it is useful for—which is to help the individual survive, thrive and reproduce. And this goes not only for fluid intelligence, but crystallized intelligence as well.
This is downright obvious on an intuitive level, but it has also been borne out in the scientific data. For example, IQ scores (which, as we have seen, measure the combination of crystallized and fluid intelligence) have been shown to correlate with all manner of positive real-world outcomes. As Hurley explains, “a recent study of 1,116,442 Swedish men whose IQs were tested at age eighteen, for instance, found that after twenty-two years, those who scored in the bottom 25 percent were over five times more likely to have died of poisoning, three times more likely to have drowned, and over twice as likely to have been killed in a traffic accident as those who scored in the top 25 percent. Overall, by middle age, for every 15 points lower on the IQ scale that a man’s intelligence was at age eighteen, his risk of dying by middle age increased by one-third and his risk of being hospitalized for some kind of assault increased by one-half. In another study, of Scottish adults born in 1921, even after adjusting for the effects of social class and childhood deprivation, every 15-point drop in IQ measured at age eleven was associated with a 36 percent increased risk of death by age sixty-five. In a host of other studies, intelligence has been repeatedly linked to the risk of getting murdered, developing high blood pressure, having a stroke or heart attack—even to early menopause, with one study finding that every 15-point gain was associated with a 20 percent reduction in the likelihood of entering menopause by age forty-nine” (loc. 187). So, yes, intelligence is useful in life—and if we can find a way to increase ours, that would be nice.
2. On the Improvability (and Unimprovability) of Intelligence
Now, while crystallized intelligence is very clearly something that can be improved (through reading books, say—or summaries of books), until very recently it was thought that fluid intelligence could really not be improved much. Specifically, it was believed that fluid intelligence is largely determined by biology. As the author explains, “as recently as 2008, the consensus among mainstream intelligence researchers was that human intelligence is just too complex, and too closely linked to innate characteristics of the brain, to be significantly modified by any straightforward training method. Sure, they agreed that exposing children to an enriched environment does generally improve their chances for reaching their potential. But not by much. Because unlike a test of physical strength, which measures only how you performed today, intelligence tests have always been pitched as an upper limit on what you can ever do: a cognitive glass ceiling, a number tattooed on the soul” (loc. 102).
Recent research, however, has begun to challenge this view. As the quotation hints at, the tide really started to turn in 2008 (with a landmark study published by the Swiss psychologists Susanne Jaeggi and Martin Buschkuehl—which study we shall get to in a moment). However, at least one hole had been poked in the immovable-intelligence armor some time before this.
Section 2. Attacking the Unimprovable Intelligence Paradigm: From Neural Plasticity to Improving Intelligence through Working-Memory Exercises
3. Michael Merzenich and Neural Plasticity
The first hint that the immovable-intelligence position might be challengeable came in the early 1980s. It was at this time that the neuroscientist Michael Merzenich performed his revolutionary work in neural plasticity. Specifically, Merzenich demonstrated that specific areas of the brain known to carry out particular mental tasks could be re-wired to perform other mental tasks normally carried out by other areas of the brain. In addition, Merzenich also demonstrated that specific areas of the brain could be enlarged and strengthened by way of practicing mental tasks known to be carried out by that part of the brain. As the author explains, “in the early 1980s… Merzenich published studies showing that, in a matter of weeks, he could change which areas of a monkey’s brain handled information from, say, the first digit of its left hand—simply by disabling the second digit. Rather than sitting idle when nerve signals stop coming, the area of the brain previously devoted to one finger begins processing information from another. Over the following three decades, Merzenich built on this observation to show that animals, including humans, could benefit from neural reassignment: as more attention is given to distinguishing between pinpoint differences in touch, sound, or sight, the area of the brain devoted to that distinction expands and, in the process, gets better at it. Dyslexic children, he found, could be trained to discern subtle differences in sounds to enable them to better understand spoken language; elderly drivers in their seventies could likewise be trained to regain the wider field of view that they had gradually lost over a period of decades” (loc. 287).
The following is a nice short video on neural plasticity:
4. Improving Attention Span and Fluid Intelligence in Subjects with ADHD: Torkel Klingberg’s Landmark Experiment
a. An Introduction to Klinberg’s Experiment
While Merzenich did not show that fluid intelligence in particular could be enhanced through training, his research at least demonstrated that this may be a fruitful line of inquiry; which is exactly what Swedish psychologist Torkel Klingberg picked-up on (loc. 280).
In 1999, Klingber took inspiration from Merzenich’s work to undertake some brain-training research of his own. Specifically, Klingberg decided to test the effect of a program of working-memory tasks on a group of 14 subjects (between the ages of 7 and 15) that had been diagnosed with ADHD (loc. 295). Klingberg hypothesized that training subjects in one variety of working-memory task would allow them to improve in other, untrained working-memory tasks, and may even allow them to improve in general intelligence (loc. 280).
Actually, Klingberg’s choice of experimenting with working-memory tasks was no accident. But in order to see why we must first take a look at just what working memory is.
b. Working Memory
Unlike short-term memory, which involves remembering a number of bits of information for a short period of time, working memory involves remembering certain bits of information while you work with and manipulate other bits of information in your mind (loc. 210, 308). So, for example, remembering a telephone number while you find a piece of paper to write it down on is an example of short-term memory, whereas performing long multiplication in your head is an example of working memory, since you need to remember the results of previous multiplications while you perform new multiplications. As the author explains, “short-term memory enables you to remember a telephone number, but working memory empowers you to multiply the first three digits of that number by the last four digits in your head… The demands of working memory explain why doing multiplication of two-digit numbers in your head (let alone four-digit numbers) is so difficult: because you have to do it in parts, and set aside the solution to one step while solving the next, placing things into the back of your mind, out of your conscious awareness, and then rapidly pulling them back to attention as necessary. Working memory is what permits a poet to play with words to discover the best expression of a given thought; it’s how we remember the second and third steps of a set of directions after completing the first” (loc. 315).
As we can see, working memory is quite a bit more complex than short-term memory; and, in fact, their natures are such that working memory seems to fit in much better with skills that we would consider to express fluid intelligence. This intuitive notion has actually been supported empirically. For example, as Hurley explains, “using complex mathematical formulae to see how… multiple tests related to each other, [Randy] Engle and his colleagues concluded that ‘working memory shows a strong connection to fluid intelligence, but short-term memory does not.’ That is, the better a person does on working-memory tests, the smarter he or she tends to be” (loc. 2187). And the correlation here does not appear to be accidental; for, as Engle and his colleagues noted, the ability to focus and control one’s attention (which is at the heart of working memory) appears to underlie fluid intelligence more broadly: “both working memory and fluid intelligence, they argued, ‘reflect the ability to keep a representation active, particularly in the face of interference and distraction” (loc. 2190).
In fact, the ability to control one’s attention (even in the face of distraction) is so crucial in fluid intelligence that Engle has even speculated they may be one and the same thing (loc. 2203-10).
c. Klingberg’s Experiment
In any event, it should now be clear why Klingberg chose to experiment with working memory tasks in his effort to boost fluid intelligence. Specifically, working memory tasks seem to be the one variety of mental exercise (outside of taking the Raven’s test) that best activates the skills used in fluid intelligence.
Now, in his experiment, Klingberg had all of his 14 subjects undergo a brain-training regimen that consisted of working through working-memory tasks of various kinds for 25 minutes per day, for 5 days a week, for 5 weeks (loc. 294). (It was just this type of training schedule that Merzenich had had success with years before—which explains why Klingber also employed it [loc. 287].)
For half of the subjects, Klingberg arranged for the tasks to get harder as the training regimen progressed, such that the subjects were always operating just at their mental capacity (a practice known as adaptive training—which practice Merzenich had also had success with in his experiments [loc. 291]). As the author explains, adaptive training is designed such that it is “adapted to the capacity limit of the individual being trained. It can’t be too easy; it can’t be too hard; it has to be right at the edge, and it has to stay at that edge, getting harder as the person gets better” (loc. 291). For the other half of the subjects (the control group) the games did not get progressively more difficult; rather, “the games started easy, and remained easy” (loc. 298).
Before and after the experiment, Klingberg tested all of his subjects on the Raven’s test, as well as several working-memory tasks that the subjects would not be trained on during the experiment (loc. 303-09). Also, while the subjects were taking these tests, Klingberg recorded their head movements, in order to gain an indication of their attention levels (loc. 303).
So what did Klingberg find? Here is Hurley to explain: “the seven kids who trained adaptively not only got better on the trained tasks, they also improved on other measures of working memory. It was as if they practiced golf and got better at basketball. What’s more, their hyperactivity, as measured by head movement, was also significantly reduced… Most incredibly, even bizarrely by the standards of orthodoxy then holding sway, the trained kids in Klingberg’s study also did much better on the Raven’s progressive matrices, long regarded as psychology’s single best measure of fluid intelligence. If the results were to be believed, the kids had gotten smarter” (loc. 311).
PART II: THE RISE OF THE BRAIN-TRAINING INDUSTRY
Given that, before Klingberg’s study, there was virtually no scientific evidence that general intelligence could be improved through mental exercises, the study itself may be seen to be revolutionary. Still, the study was very small (with just 14 subjects), and was published in a relatively minor publication (the Journal of Clinical and Experimental Neuropsychology [loc. 320]), and thus as revolutionary as it was, Klingberg’s work was more or less ignored by both the media and the scientific community (at least in the short term) (loc. 377).
5. The Brain-Training Industry
Nevertheless, the importance of Klingberg’s work did not go lost on Klingberg himself. Indeed, Klingberg immediately recognized a business opportunity in his findings, and he (together with a few colleagues) soon launched a brain-training company called Cogmed.
a. Cogmed
Through Cogmed, Klingberg and his collaborators developed a brain-training program meant to help people with ADHD improve their cognitive functioning. As Hurley explains, “by the time his study was published, Klingberg and some colleagues had already partnered with the Karolinska Institute to form a company, Cogmed, to turn working-memory training into a business… The initial target market was children with ADHD, whose parents hoped to find something other than drugs to improve their children’s attention” (loc. 709).
To get an idea of what Cogmed’s brain-training program looks like, Hurley payed a visit to Klingberg (who sold the company to Pearson in 2010 [loc. 713]). Here’s what Klingberg had to say about the program that he helped design: “‘There are twelve tasks,’ he said. ‘They’re all visuospatial. The role of attention in working memory almost always has a spatial dimension. When you’re paying attention—even when you’re paying attention to me talking here in this cafe—there’s a spatial component. When there’s a loud noise, you might shift your attention to where it’s coming from. Being able to maintain your spatial focus on me is important for you right now. Even though it’s words coming from me, there’s an important component of space. So if you can improve the stability of that spatial aspect, you will be better at visuospatial tasks and be better at keeping your focus on me rather than on that noise over there’” (loc. 737).
Wanting to get a more first-hand understanding of the program, Hurley decided to try a few of the training tasks for himself. Here is the author’s account of a couple of the tasks: “I clicked one called 3D Grid. It showed the inside of a cube, looking down on it as though the top were removed, with each of the four sides and the bottom divided into four panels. Once the game began, some of the panels lit up; I then had to click on them in sequence to show that I remembered. Another game, called Hidden, showed a standard numeric keypad, the kind used on cell phones and calculators. The keypad was hidden while a man’s voice recited a short list of numbers. When his list was complete, the keypad reappeared, and I was supposed to click on the list—in reverse order” (loc. 744). Sure enough: working-memory games with a visuospatial aspect.
In terms of cost, 25 sessions of the program (working with a trainer) costs $2,000 (loc. 758).
With the launching of Cogmed, the brain-training industry was officially off the ground. And it didn’t take long for other companies to join the fray (as we shall see in a moment). Now, over the years, numerous brain-training companies have popped up; in the book, though, Hurley confines himself to investigating and reporting on only those programs that have generated at least some scientific evidence in their favor. We shall now give a brief introduction to each of these programs (as for the scientific evidence behind them, this will be explored in Part III).
b. LearningRx
The next brain-training program that Hurley investigates, called LearningRx, launched mere months after Cogmed had—in 2003 (loc. 1056). Unlike Cogmed, LearningRx is not targeted specifically towards people with ADHD; however, the program does seem to be popular among young people suffering from mild cognitive disorders, such as ADHD and dyslexia (loc. 1017, 1049).
LearningRx also differs from Cogmed in that includes many varieties of cognitive tasks (not just working-memory tasks), from pattern-recognition tasks (a la Raven’s test), to dexterity tasks, to distraction-resistance challenges, to reading and math exercises (loc. 1003, 1010, 1017, 1038-42).
Like Cogmed, LearningRx’ program includes one-on-one attention from one of the company’s in-house ‘Brain Trainers’ (loc. 996). In terms of pricing, the program costs $12,000 for 3 sessions per week for a full school year (loc. 1020). This was the most expensive brain-training program that Hurley came across (loc. 992).
c. Posit Science
In 2004, a year after LearningRx launched, Michael Merzenich (the very man who had performed the pioneering work in neural plasticity that had inspired Klingberg) started a brain-training company of his own called Posit Science (loc. 922). Like Klingberg’s Cogmed program, Merzenich designed his program to help people burdened with mental deficits. Rather than focusing on people with ADHD, though, Merzenich designed his program to improve mental functioning in individuals with severe cognitive disorders, such as Alzheimer’s disease, traumatic brain injury, and schizophrenia (Ioc. 922).
While Posit Science’s program does include some tasks that challenge working-memory (loc.943), the program also includes tasks designed to activate and exercise visual and auditory perception—including the perception of visual and auditory gradients (loc. 947). For example, one of the tasks in Posit “challenges the user to follow the movement of two or three balls floating on the computer screen amid a bunch of other balls” (loc. 904). Meanwhile, “with the ‘sound sweeps’ task, you listen to tones that are rising or falling, like an ambulance siren approaching or receding. The faster the tones are played, the harder it is to distinguish whether they are rising or falling [which is precisely what you are meant to do]” (loc. 947).
Just how are these sensory-perception tasks supposed to improve cognitive functioning? Merzenich argues that higher cognitive functioning is built up from simpler skills, and exercising these simpler skills strengthens them and leads to better functioning at higher levels. As Merzenich explains, “‘We’re trying to assure generalization by first training the brain to make these elementary distinctions… We go from the most basic sound dimensions of phonemic distinction to vowels and consonants, to distinctions between words, to narratives, and ultimately to the manipulation of information in cognitive control. The goal is to drive these fundamental processes to correctly represent information with greater power and salience, and then trying to ensure that the person is using this in higher analysis and thought. The simple fact is in a normal adult life, you don’t practice enough on the things that gave you the powers you gained during childhood. You become a user of mastered skills. You’re not working to maintain the high abilities on which it was all based’” (loc. 960).
As mentioned above, Posit Science’s program was originally intended to improve the mental functioning of people with severe cognitive disorders. However, Posit has since come out with a version of its program intended for the general public, available here: https://brainhq.positscience.com/default/start# (loc. 985).
d. Brain Age and Lumosity
Speaking of the general public, the last 2 programs that Hurley touches on are both targeted to this audience. The first major brain-training program to come out that was intended for the general public was one called Brain Age, put out by the computer game company Nintendo in 2005 (loc. 700). Unlike other brain-training programs, though, Nintendo does not claim that its program yields cognitive benefits. Rather, Nintendo “insists the software is purely for entertainment and declines to support any benefits” (loc. 703). Given that this is the case, Hurley decided not to investigate Nintendo’s program in any detail.
That leaves us with the final brain-training program that Hurley explored: Lumosity. Lumosity was launched in 2007. Like Nintendo’s Brain Age program, Lumosity was designed from the beginning for a general audience. Unlike the Brain Age program, though, Lumosity does claim to be able to improve cognitive functioning, and to have scientific evidence to prove it (loc. 855).
It is perhaps for these reasons that Lumosity’s star has risen so high, so fast. Indeed, Lumosity has quickly become an industry leader, and boasts over 40 million customers (compared to Brain Age’s 19 million [loc. 699]). As Hurley explains, “Lumosity launched in 2007 and began growing 20 to 25 percent every quarter. In June 2011, the firm received $32.5 million from a venture capital firm. Within a year, according to the company, their number of members had reached 25 million. By April 2013, they claimed 40 million members” (loc. 852).
From the Lumosity exercises that Hurley describes, the program appears to lean heavily on working-memory tasks similar to the ones used in the Cogmed program (loc. 855-63). For example, “for Monster Garden… you see a bunch of monsters pop up on this grid. Then they go away, and you have to navigate a path through the grid without stepping on any of the squares where the monsters were” (loc. 862).
With regards to Lumosity’s pricing, the program is relatively inexpensive. As Hurley explains, “anyone can sign up online, for a fee currently priced at $14.95 per month or $79.95 per year” (loc. 866).
PART III: THE SCIENCE OF BRAIN-TRAINING
Keep in mind that by this point (2007) the only scientific evidence that had been independently established which indicated that brain-training is even possible was Torkel Klingberg’s small study of 14 subjects diagnosed with ADHD and trained with working-memory tasks back in 2002 (it is true that many of the companies mentioned above conducted experiments on their own products and found positive results—but these types of conflict-of-interest studies must, of course, always be taken with a grain of salt).
And as for Klingberg’s study, it had been all but ignored by the scientific community. Indeed, while an entire industry had grown up around brain-training programs, the scientific community, for its part, continued to believe that boosting brain power through training was more or less impossible. Until 2008, that is.
6. The Dual N-Back Experiment: Susanne Jaeggi and Martin Buschkuehl
a. An Introduction to Jaeggi and Buschkuehl’s Dual N-Back Experiment
It was in this year that the Swiss psychologists Susanne Jaeggi and Martin Buschkuehl stumbled upon Klingberg’s 2002 study, and decided to give it a closer look. Specifically, Jaeggi and Buschkuehl decided to run their own experiment to see if they could match Klingberg’s results. (actually, Buschkuehl had stumbled upon Klingberg’s study years before, just after it was published, but it was only in 2008 that Jaeggi and Buschkuehl finished and published their own study [loc. 314, 377).
Jaeggi and Buschkuehl’s experiment ran as follows: The two invited a couple of dozen student subjects into their lab at the University of Bern. Jaeggi and Buschkuehl then had all of their subjects undergo a brain-training regimen that, similar to Klingberg’s, consisted of 25 minutes of training, 5 days a week, for 4 weeks using a working-memory task (as with Klingberg’s study, Jaeggi and Buschkuehl used adaptive training—where the tasks get progressively more difficult as the subject improves [loc. 351]). In Jaeggi and Buschkuehl’s case, the working-memory task that they chose was one called dual N-back.
b. The N-Back Task, and the Dual N-Back Task
First, let me explain the simpler version of this task: N-back. In N-back, the subject is presented with a string of letters (out loud) over the course of a given time period. So, the string of letters may look something like this: a c a f g l l m q r r q. In the first and easiest level of the task (called 1-back), the subject must press a key every time they hear a letter repeated twice in a row (so, in the example above, the subject would press a key upon hearing the second l, and then again after hearing the second r). Once the subject displays a certain amount of proficiency at this level, they move to the next level, called 2-back. In 2-back, the subject must press a key every time they hear a letter that they heard 2 letters previously (so, in the example above, the subject would press a key upon hearing the second a). Likewise with 3-back, the subject must press a key every time they hear a letter they heard 3 letters previously (so, in the example, the subject would press a key after hearing the second q). Again, as the subject masters this level they move to the next, and there is no end to how many levels the task potentially has.
In dual N-back, the subject plays two games of N-back—at the same time! Only the second game of N-back involves a sequence of dots presented in a spatial matrix. As the author explains, “your mission is to keep track of both the letters and the dots as they just keep coming. So, for example, at the 3-back level, you would press one button on the keyboard if you recall that a spoken letter is the same one as was spoken three times ago, while simultaneously having to press another key if the dot on the screen is in the same place as it was three times ago. That’s right. Ouch” (loc. 347). (You can play dual N-back for free online here: http://brainscale.net/n-back/training.)
c. The Results of Jaeggi and Buschkuehl’s Experiment
Both before and after the training regimen, the researchers tested their subjects on the classic fluid intelligence test, the Raven’s. Here’s Hurley with the results of the experiment: “Within days, most of [the subjects] had jumped from mastering the 3-back to dabbling with the 5-back. By the end of the four weeks, some got as far as 8-back. And afterward, when they took the Raven’s again, their average scores had jumped by over 40 percent” (loc. 368).
This was an incredible result, and Jaeggi and Buschkuehl, who had been skeptical coming in, could hardly believe it themselves (loc. 368). So they decided to run the experiment again, this time adding a control group (who would not undergo a training regimen), as well as 2 new experimental groups, who would undergo the training regimen for a lesser period of time (to see if there was a dose effect). “Sure enough,” Hurley explains, “at the conclusion of the study, those who practiced the dual N-back for just twelve days saw an average gain of a little over 10 percent on their matrices test. Those who practiced for seventeen days gained more than 30 percent, and those who practiced for nineteen days increased an astonishing 44 percent” (loc. 375).
7. The Response to Jaeggi and Buschkuehl’s Experiment
Jaeggi and Buschkuehl wrote up their results and had them published in the Proceedings of the National Academy of Sciences on May 13, 2008 (loc. 377). This time, the world took notice. As the author explains, “unlike Klingberg’s study, which had received little notice by the popular press, Jaeggi and Buschkuehl’s study became an immediate sensation, making headlines in newspapers around the world. ‘Brain Training’ Games do Work, Study Finds,’ announced the British newspaper the Daily Telegraph. ‘Memory Training Shown to Turn Up Brainpower’ was the headline in the New York Times” (loc. 377).
And it wasn’t just the media that took notice. The scientific community, too, was intrigued, and soon enough labs all over their world launched their own experiments to see if the results could be replicated. And, by and large, they were.
One of the many researchers who was able to find positive results out of a brain-training regimen was Jason Chein, assistant professor of psychology at Temple University. As Chein explains, speaking of Jaeggi and Buschkuehl, “‘my findings support what they’ve done…’ [Hurley adds that] Chein had seen improvements in cognitive abilities after training people not with N-back but with other working-memory tasks, the verbal and spatial complex-span tasks. ‘I’ve never replicated exactly what they do. But across a number of labs, using similar but different approaches to training, we have had related successes. Cautious optimism is the best way to characterize the field now’” (loc. 392).
As of today, Hurley notes, some 75 studies have been performed that demonstrate positive cognitive effects from brain-training (loc. 192, 2247, 2334). As the author explains, “by my count, seventy-five… randomized, placebo-controlled studies have now been published in peer-reviewed scientific journals confirming that cognitive training substantially improves intellectual abilities. Twenty-two of those studies specifically found improvements in fluid intelligence or reasoning, while the remaining fifty-three found a variety of other significant benefits in abilities such as attention, executive function, working memory, and reading. Results have now been seen not only in elementary-school children, but in preschoolers, college students, the middle-aged, and the elderly. Healthy volunteers have benefited, as have people with disorders including Down syndrome, schizophrenia, traumatic brain injury, alcohol abuse, Parkinson’s disease, chemotherapy-treated cancer, attention-deficit/hyperactivity disorder (ADHD), and mild cognitive impairment (a common forerunner of Alzheimer’s disease). Gains have been seen to persist for up to eight months after the completion of training” (loc. 198).
Interestingly, brain-training with working-memory tasks has not only been shown to help improve fluid intelligence, it has also been shown to improve emotional intelligence (via improving emotional and behavioral control). As Hurley explains, “in March 2013, the Journal of Neuroscience published a randomized study by Cambridge University researchers showing that people who spent just twenty days training for about a half hour a day on a version of N-back that incorporated emotion-laden words like ‘dead’ and ‘evil,’ as well as images of faces displaying fear, anger, sadness, or disgust, significantly improved their performance on a gold-standard measure of emotional control, called the emotional Stroop task. Those gains, by the way, were accompanied by greater activity in the part of the frontal lobes associated with emotional regulation, as revealed by fMRI brain scans” (loc. 202).
Still, not all of the researchers who have studied brain-training regimens have come up with positive results. Hurley identifies 4 studies in particular that found no effect on fluid intelligence out of working-memory regimens. The author explores each of them at length in the book (something we will not do here), and also interviews many of the researchers behind the studies. What is peculiar is that many of the researchers behind these studies are not only skeptical that any benefit can be derived from working-memory training, they are downright hostile towards the idea, and insist that much of the research in favor of the notion is flawed (loc. 2215-34, 2417-20).
So, where does the truth lie? Based on a review of the studies that found negative results, as well as a review of the meta-studies (which compile the results of large numbers of similar studies), it appears reasonable to conclude the following: while the field of building brain power through cognitive training is still young, and there is much to learn about exactly what regimens, and what conditions produce the best results, the evidence points towards the idea that working-memory training does show encouraging signs of sharpening cognitive skills of various kinds (including increasing general intelligence) to a statistically significant degree in many subjects (loc. 2236-44, 2347-91, 3059-62). Also, the training appears to have the greatest effect on those who are low-functioning to begin with (that is, those who score low on the Raven’s and IQ tests etc.), and the least effect on those who are high-functioning (loc. 2324).
Based on the totality of the evidence, and the success that Jaeggi and Buschkuehl had had with the dual N-back task in particular, Hurley decided to add the dual N-back to his brain-training program (loc. 402, 499, 1837).
8. The Science behind Commercially-Available Brain-Training Programs
So much for the scientific studies of working-memory training. But what about the commercially-available brain-training programs? As mentioned above, many of these programs contain at least a component of working-memory training (with some of these programs, such as that offered by Cogmed, consisting entirely of working-memory tasks). However, we may well ask whether the working memory tasks offered by these companies match those that have shown positive results in the studies. Also, many of the commercially available brain-training programs include components that have little or nothing to do with working-memory training. So, just what evidence is there that these training programs actually work?
Before Jaeggi and Buschkuehl’s study, the scientific community simply wasn’t interested in this question, for the assumption was that brain-training just didn’t work. Since Jaeggi and Buschkuehl’s study, though, brain boosting has become a respectable topic (indeed, even trendy), and the question regarding the efficacy of at least some brain-training programs has in fact now been studied (at least to a small degree). Of course, we already know this, since, as mentioned above, Hurley limits himself in the book to discussing only those brain-training programs for which there is some independent scientific evidence that they work.
However, it must be said that the number of studies focussed on these programs is relatively few, and their results often relatively modest (though nevertheless statistically significant). Let me just briefly outline one study from each of the brain-training programs mentioned above.
a. Cogmed
When it comes to Cogmed (Torkel Klingberg’s program), one study compared the program with a placebo program that did not get more difficult as the regimen unfolded. The study found that “among twenty children who had survived either brain cancer or leukemia, those who trained with Cogmed saw substantial improvements compared to the placebo group on their visual working memory and in parent-rated learning problems” (loc. 808). The lead researcher, neuropsychologist Kristina K. Hardy, reported the following to Hurley: “‘not everybody has been able to make a lot of gains. But I’ve had some kids who not only reported that they saw big changes in their life after training, but when we brought them back to the lab and did neuropsychological testing, we saw great changes, too. At a gut level, I do believe some kids can do better with this training. I don’t believe that every kid is going to. But in my most recent trial, we saw about 50 to 60 percent of children make gains that I consider clinically meaningful’” (loc. 815).
b. LearningRx
When it comes to LearningRx (the most expensive program), the psychology professor Oliver W. Hill Jr. of the Virginia State University “compared 340 middle-school students who spent two hours a week for a semester at their schools’ computer labs using the online version of LearningRx exercises to an equal number of students who received no such training. Those who played the online games, he found, improved significantly not only on measures of cognitive abilities compared to their peers, but also on Virginia’s annual Standards of Learning exam. He’s now conducting follow-up study of college students in Texas and said he sees even stronger gains when the training is one-on-one” (loc. 1065).
c. Posit Science
As for Post Science (Merzenich’s program—now owned by Pearson), one study “published in May 2013, involved 681 people in two age groups: fifty to sixty-four and sixty-five-plus. Compared to the active control group, assigned to do computerized crossword puzzles, participants of all ages who trained for ten hours with Posit’s speed-of-processing program gained a wider ‘useful field of view,’ the kind necessary to see things in the periphery when driving, and also showed significant improvements on a number of untrained cognitive tests. Converted to years of protection against age-related cognitive declines… the results of just ten hours of training reflected up to six years of protection” (loc. 969).
d. Brain Age, and Lumosity
When it comes to Brain Age, despite the fact that Nintendo insists that its program is for entertainment purposes only, a few studies have found that the program does offer some protection against Alzhmeimer’s disease (though Hurley does not offer any specifics of these studies) (loc. 702).
Finally, when it comes to Lumosity, Shelli Kessler, a psychologist and assistant professor at Stanford, performed a study “using a randomized design involving forty-one breast cancer survivors, twenty-one of whom were assigned to train for forty-eight sessions over twelve weeks, while the remaining twenty were put on a waiting list. Kesler reported in the journal Clinical Breast Cancer: ‘Cognitive training led to significant improvements in cognitive flexibility, verbal fluency and processing speed, with marginally significant downstream improvements in verbal memory as assessed via standardized measures. Self-ratings of executive functioning skills, including planning, organizing, and task monitoring, also were improved in the active group compared with the wait list group’” (loc. 877).
When Hurley tracked Kesler down, she reported the following: “‘There’s pretty strong evidence that several different types of medical problems, including cancer, HIV, diabetes, and MS, are associated with significant cognitive issues. I see these patients in clinic, and I almost always recommend that they try Lumosity or something like it. Fundamentally I do believe it helps. Even if you’re a healthy person, this is a good thing to consider doing, to keep your brain active and healthy. My only hesitation is that if you start claiming it will work for everyone in every situation, that’s where you can get in trouble” (loc. 881).
Considering the scientific evidence, the price of the programs, and the intended audience of each, Hurley decided to include only Lumosity in his brain training program (loc. 822-26, 914, 1066-73).
So much for brain-training programs. But what about other varieties of interventions that have been purported to build brain power—such as learning a new language or musical instrument, or meditating; physical exercise; food items, such as fish oil, blueberries, vitamin b, creatine, and the Mediterranean diet; pills such as Adderall and Provigil; and transcranial direct current stimulation? Part IV will be devoted to the scientific evidence behind these interventions.
PART IV: THE SCIENCE BEHIND OTHER BRAIN-BOOSTING INTERVENTIONS
Section 3. Mental Exercise: Learning a Musical Instrument or a Second Language, and Meditating
9. Music
a. Baby Mozart
You have probably heard of the Mozart effect: the idea that babies can be made smarter simply by playing them classical music in the womb. This idea came out of a study that was performed in 1993 by the psychologist Frances H. Rauscher working out of the Center for Neurobiology of Learning at the University of California in Irvine (loc. 1357). Weirdly, Rauscher’s study did not look at babies at all, but at college students! Here’s Hurly to explain: “Thirty-six college students (not babies) spent ten minutes each listening to either silence, taped instructions for relaxing, or Mozart’s Sonata for Two pianos in D Major. Immediately after each listening session, they took a ‘spatial reasoning’ test, the kind that requires a person to accurately imagine rotating a three-dimensional object depicted on a piece of paper. Their average spatial IQ score after ten minutes of silence was 110, and after the relaxation tape it was 111. But after just ten minutes of listening to Mozart, their average score was 119. ‘Thus, the IQs of subjects participating in the music condition were 8-9 points above their scores in the other two conditions,’ Rauscher and colleagues reported in the October 14, 1993, issue of Nature. Cue the trumpets and the big bass drums. Even though the small study involved college students, and even though the paper made clear that the effect lasted only for ten to fifteen minutes, somehow our popular culture concluded that Mozart makes babies smarter, prodded along by an over-the-top book, The Mozart Effect, and its sequel, The Mozart Effect for Children” (loc. 1368).
Unfortunately, when other researchers attempted to replicate Rauscher’s results, they found that Mozart had virtually no effect on IQ whatsoever. As the author explains, by the year 2000 “the journal Nature had already published two devastating follow-ups to Rauscher’s paper: a meta-analysis of twenty other studies that had tried to replicate her study and found, on average, a gain of just 1.4 IQ points after listening to Mozart, and a new attempt at replication, which found nothing at all” (loc. 1379).
As of now, therefore, there is evidence of the Mozart effect neither in babies nor adults.
b. Learning a Musical Instrument
When it comes to learning a musical instrument, however, here the studies are more promising. For example, the psychologist E. Glenn Schllenberg, working out of the University of Toronto, performed a study wherein he took 144 six-year-olds and had one-quarter take keyboard lessons, one-quarter take voice lessons, one-quarter take drama lessons, and one quarter take no lessons, all for a full school year (36 weeks) (loc. 1394). Here’s what he found: “After thirty-six weeks, the IQ of all four groups had gone up slightly—a normal result of entering elementary school—but the music-trained students went up significantly higher than the others. Scores went up by 3.9 points for those who received no lessons, compared to 5.1 points for the students trained in drama, 6.1 points for those trained on keyboard, and 7.6 points for those given voice lessons. ‘Compared to children in the control groups, children in the music groups exhibited greater increases in full-scale IQ,’ Schellenberg concluded. The higher IQ scores, he noted, were accompanied by higher grades for the music-trained students at the end of their school year. (Why the voice-trained students did better than the keyboard-trained was unknown)” (loc. 1397).
In addition, several similar studies have since confirmed Schellenberg’s results (loc. 1405-13). Based on this evidence, Hurley decided to add learning a new musical instrument (the lute) to his brain-training regimen (loc. 1417-21).
10. Learning a Second Language
As for the cognitive benefits of learning a second language, here the scientific evidence is mixed. There is some evidence that learning a second language has some effect in helping stave off Alzheimer’s disease (but only when the second language is learned in adulthood—not in childhood) (loc. 1219-22). However, the evidence regarding the effect of bilingualism on intelligence is less impressive. As Hurley explains, “a 2009 paper from researchers in Italy did find that seven-month-old infants raised in bilingual homes were better at responding to a computerized test of attention than children raised in monolingual homes. And a series of studies by psychologist Ellen Bialystok of York University in Toronto has found benefits in some, but not all, measures of cognitive control in young bilingual children over those who speak just one language. However, one of the largest studies on the subject, involving 266 young adults, concluded, discouragingly, that ‘being bilingual does not provide young adults advantages in cognitive processing and that being trilingual results in lower, rather than greater, cognitive control” (loc. 1230).
Based on this evidence (and the amount of time needed to learn a new language), Hurley decided to leave this activity out of his brain training program (loc. 1229-33).
11. Meditation
There is just one other variety of mental activity that we must look at, and that is meditation. Meditation has numerous incarnations, but the one that has garnered the most attention in the brain-boosting field is one known as mindfulness meditation. “Mindfulness meditation,” Hurley explains, “emphasiz[es] moment-to-moment awareness of whatever thoughts, feelings, or bodily sensations come to mind, without judgment or reflection, letting them come and go like passing clouds, while only attention and alertness remain” (loc. 1451).
Interestingly, a number of studies have been performed showing several impressive cognitive benefits from mindfulness meditation. For example, one study recruited 80 undergraduate students from the University of Dalian and had half of the subjects perform IBMT (a form of mindfulness meditation) for 20 minutes per day for 5 days, while the control group received relaxation training only (loc. 1450-54). Here is Hurley with the results: “before and after, the students were tested on the Raven’s standard progressive matrices; on a measure of attention… called the Attention Network Test; as well as for anxiety, depression, anger, fatigue, and the amount of stress-related cortisol in their saliva. On the attention test, those who mediated showed significantly better cognitive control than students in the control test. Raven’s scores went up more for the meditators than for controls; and all the other measures improved significantly” (loc. 1455).
The very same researchers followed this study up with another that focussed on the neural effects of IBMT and found this: “eleven hours of IBMT resulted in greater integrity and efficiency of white matter—the neural wires and cables connecting neurons—emanating from the anterior cingulate cortex, or ACC. Shaped like an upside-down Nike swish, and located a couple of inches above and a few inches behind the eyebrows, the ACC is closely connected to the prefrontal cortex. It’s known to work hardest during tasks requiring cognitive control and when mental effort is required to learn or solve problems” (loc. 1459).
Given the evidence in favor of mindfulness meditation, Hurley decided to add it, too, to his brain training program (though he would later ditch the activity half-way through his program—ostensibly because he had trouble finding a quiet place to do it [loc. 1956]).
*In the beginning, Hurley used a mindfulness meditation CD by Jon Kabat-Zinn. Here is Kabat-Zinn in action:
Section 4. Physical Exercise
12. Exercise
So much for exercising the brain. But what about exercising the body? Is there any evidence that this kind of activity helps boost brain power? Yes, actually. Study after study has confirmed that physical exercise, both in the form of aerobic activity and resistance training, has a beneficial effect on all sorts of cognitive functions from memory to attention-shifting to decision-making.
a. Aerobic Activity
Take aerobic exercise, for example. One of the leading researchers in looking at how aerobic exercise affects cognition is Arthur Kramer, a psychologist at the University of Illinois at Urbana-Champaign. Kramer sums up the research thus: “in the past ten years, there have now been at least four meta-analyses looking at published studies… they all come to the same conclusion: there is a significant effect of fitness training on cognition. We have lots of studies done all over the world. What’s interesting is you’re not training any aspect of cognition. You’re not learning anything. You’re just walking, swimming, or bicycling. It’s just three times a week. But despite that, you get better almost across the board in terms of different aspects of memory, perception, and decision making. It’s amazing that we find the results we do with such a small change in a person’s life” (loc. 1306).
b. Resistance Training
And it’s not just aerobic exercise that has a beneficial effect on cognition. Similar results have been found with resistance training as well. For example, the psychologist Teresa Liu-Ambrose conducted a study wherein she randomly assigned 155 women between the ages of 65 and 75 to one of the following exercise routines: “once-weekly resistance training, twice-weekly resistance training, or (as a control group) twice weekly balance and tone training” (loc. 1320). Here’s what she found: “On a standard measure of cognitive control, both resistance training groups improved by over 10 percent, compared to a decline of half a percent in the tone and balance group” (loc. 1324).
In a similar study, Liu-Ambrose later found that “the group assigned to resistance training improved on tests of attention, conflict resolution, and memory. On fMRI tests, as well, only the resistance trainers showed signs of increased activity in three regions of the cortex” (loc. 1327).
Based on the evidence, Hurley decided to include a boot camp regimen in his training program—as this regimen includes both an aerobic element and a resistance training element (loc. 1355).
Section 5. The Easy Routes to Building