The myth has surely motivated many people to strive for greater creativity and productivity in their lives, which certainly isn't a bad thing. The comfort, encouragement, and hope that it's generated almost surely help to explain its longevity. But, as Carl Sagan (1995) reminded us (see Introduction, p. 11), if something sounds too good to be rue, it probably is. Myth #2 Some People Are Left-Brained, Others Are Right-Brained The next time somebody tries to sell you a book or device for retraining your allegedly flabby right hemisphere, reach for your wallet. Then clasp it firmly to your chest and run as fast as you can. Like some other myths in this book, the one you 're about to encounter has a grain of truth to it. Nevertheless, this grain can be a bit hard to find amidst the mounds of misinformation that bury it. Are some people left-brained and others right-brained? There's good evidence that the two sides of the brain, called hemispheres, differ in their functions (Springer & Deutsch, 1997). For example, different abilities are more affected by injuries to one side of the brain than the other, and brain imaging techniques demonstrate that the hemispheres differ in their activity when people engage in various mental tasks. By far the most dramatic evidence for laterality of function the superiority of one or the other hemisphere for performing certain tasks—comes from patients who've undergone a "split brain" operation. In this rarely performed procedure, surgeons sever the nerve tracts connecting opposite points in the brain's left and right hemispheres in a last-ditch attempt to control severe epilepsy. The large pathway connecting these hemispheres, the main target of the split-brain operation, is the corpus callosum ("colossal body"). Roger Sperry shared the Nobel Prize in 1981 for his landmark studies of split-brain patients, and a fascinating lot they are (Gazzaniga, 1998). Once they'd recovered from surgery, they appeared deceptively normal in their everyday activities. But once Sperry tested them in the laboratory, it became apparent that the two halves of their brains were working independently. Each side operated without awareness or knowledge of the other. In Sperry's laboratory tests, patients fixate their eyes at the center of a screen, on which the researcher briefly flashes words or pictures. With the eyes immobilized, information flashed to the left of the fixation point goes to the right hemisphere and the opposite is true of information presented to the right of the fixation point (that's because the optic pathways on each side of the visual field cross over to the other side). In more ordinary situations, this separation of information doesn' t occur because patients constantly move their eyes about their surroundings. As a result, the input normally reaches both hemispheres eventually. When it doesn 't, though, some decidedly peculiar things can happen. The right hemisphere receives input from and controls the movements of the left side of the body, and the left hemisphere does the same for the righ right-handers, and most lefties as well, the primary areas for language reception and production are in the left hemisphere. Thus, if we restrict new information to the
right-handers, and most lefties as well, the primary areas for language reception and production are in the left hemisphere. Thus, if we restrict new information to the right hemisphere. the left hemisphere—which is more verbal than the right will be unable to tell us what the input was, and it may be perplexed to see the lefthand acting on the segregated knowledge. for reasons it can't fathom. For example, if the researcher shows the right hemisphere of a split-brain subject a photograph of a naked man, she may giggle. Yet when asked what she's giggling about, the subject (her left hemisphere. that is) won't be able to say. Instead, she may cook up a plausible-sounding reason ("That photo reminds me of my uncle George. who's a really funny guy"). Split-brain subjects may even do something with their right hand. like assemble a group of blocks to fit a pattern. utterly oblivious of the fact that their left hand is following a few seconds behind, undoing all the good work. This much is well established. The dispute concerns the uniqueness of the kinds of tasks handled by the nvo hemispheres and how ffey go about it. In this regard, brain researchers have become more cautious in recent years while many pop psychologists have run wild. Using Sperry's techniques. researchers have confirmed that the left and right hemispheres are relatively better at different mental activities. Note. however, that we wrote relatively better. The two halves of the brain differ in how they process tasks rather than what they process (McCrone. 1999). Let's take language. for example. The left hemisphere is better at the specifics of speech, such as grammar and word generation, whereas the right hemisphere is better at the intonation and emphases of speech (what's known as "prosody"). Alåough the right hemisphere is better at nonlinguistic functions that involve complex visual and spatial processes, the left hemisphere plays some role in these capacities if we give it the chance. The light brain is better at dealing with a general sense of space, whereas corresponding areas in the left brain become active when die person locates objects in specific places. In many cases, it's not that one hemisphere or the other can't perform a given task; it's just that one of them can perform it faster and better than the other. So it tends to grab die assignment first. Of course, ordinary people aren't, as left brain/right-brain aficionados suggest, just split-brain patients who haven't gotten around to having their corpus callosums snipped. In the nonnal brain, the side that's first off the mark will call for help from across the way. As long as the left-right pathways are intact, the two hemispheres share information extensively. Indeed. brain imaging research shows that the two hemispheres routinely communicate during most tasks (Mercer, 2010). After a split-brain operation. this cooperation isn't possible, so the separated systems limp along as best ffey can. Therefore, the ways in which the two sides of brain differ are far more limited than pop psychology's "hemispheHcity" entrepreneurs suggest (Aamodt & Wang, 2008; Corballis, 1999, 2007; Della Sala, 1999). On balance. the two hemispheres are much more similar dian different in their functions (Geake, 2008). Modern neuroscientists have never agreed with many New Age "hemisphere trainers," who claim that the brain's two halves house totally dissimilar minds that approach the world in radically different ways, with one (the left) side an accountant and the other (die right) side a veritable Zen master. Robert Ornstein was among those to promote the idea of using different ways to tap into our "creative" right brains versus our intellectual left brains in his 1997 book, The Right Mind: MaEng Sense of the Hemispheres. Moreover, scores of educational and business programs de-emphasize getting die "right' answers on tests in favor of harnessing crati•ve abAity. Such programs as the Applied Creative Thinking Workshop have trained business managers to develop the untapped capacities of their right brains (Hermann.
1996). Furthermore, the enormously successful book. Drawing on the Right Side of the Brain (Edwards, 1980), which has sold over 2.5 million copies, encourages readers to unleash their artistic abilities by suppressing their "analytical" left hemispheres. Even cartoonists have jumped on the bandwagon; one shows a student holding an exam emblazoned with a big "F' who tells his professor, "It' s not fair to flunk me for being a right-brain thinker." The urge on the part of pop psychologists to assign all mental abilities to unique left and right compartments probably owes more to politics, social values, and commercial interests than to science. Its detractors have dubbed this extreme view "dichotomania" because of pop psychologists' tendency to dichotomize the two hemispheres' functions (Corballis, 1999). The notion was embraced enthusiastically by New Age proponents of the 1970s and 1980s, largely because it offered a rationale for world-views that were mystical and intuitive. hemisphere "logical," "linear," "analytical," and "masculine." In contrast, they proclaimed the allegedly warm and fuzzy right hemisphere "holistic," "intuitive," "artistic," "spontaneous," "creative," and "feminine" (Basil, 1988; Zimmer, 2009). Arguing that modem society undervalues the right hemisphere's touchy-feely mode of approaching the world, dichotomizers touted fanciful schemes for boosting this hemisphere's activity. Their books and seminars promised to free us of the barriers to personal growth imposed by an inflexible school system that favors "left hemisphere thinking." Yet an expert panel, assembled by the U.S. National Academy of Sciences, concluded that " . we have no direct evidence that differential hemispheric utilization can be trained" (Druckman & Swets, 1988, p. 110). The panel concluded that behavioral training could probably enhance different styles of learning or problem solving, but that such improvements were not due to differences in the two hemispheres' functioning. If the behavioral exercises promoted for right hemisphere calisthenics might yield a few benefits, we can't say the same for the far-fetched "brain tuners" sold for the same pumoses (Beyerstein, 1985, 1999a). Numerous devices of this sort allegedly harmonize or synchronize the activity of the two hemispheres. One of the most successful of these schemes was invented by a former public relations executive with no formal training in neuroscience. Like others of its ilk, the device supposedly synchronizes brain waves across the hemispheres by means of feedback signals. Probably because of the placebo effect (see Introduction, p. 14), the product found scores of satisfied customers. Yet even if the devices synchronized left-right brain waves, there's no reason to believe that making the two hemispheres resonate in this fashion would be good for us. In fact, if the brain is working optimally, this is probably exactly what you wouldn't w O Help Optimal psychological performance usually requires differential activation rather than synchronization of the hemispheres (Beyerstein, 1999a). The bottom line: Don't be taken in by the claims of dichotomizers with a seminar to sell or marketers of hemispheric synchronization gizmos that souiOd too good
The bottom line: Don't be taken in by the claims of dichotomizers with a seminar to sell or marketers of hemispheric synchronization gizmos that sound too good to be true. Current research on hemispheric differences, even by those responsible for discovering left—right specializations, focuses on showing how the normal works in an integrated fashion (Corballis, 2007; Gazzaniga, 1998; McCrone, 1999).
right-handers, and most lefties as well, the primary areas for language reception and production are in the left hemisphere. Thus, if we restrict new information to the right hemisphere. the left hemisphere—which is more verbal than the right will be unable to tell us what the input was, and it may be perplexed to see the lefthand acting on the segregated knowledge. for reasons it can't fathom. For example, if the researcher shows the right hemisphere of a split-brain subject a photograph of a naked man, she may giggle. Yet when asked what she's giggling about, the subject (her left hemisphere. that is) won't be able to say. Instead, she may cook up a plausible-sounding reason ("That photo reminds me of my uncle George. who's a really funny guy"). Split-brain subjects may even do something with their right hand. like assemble a group of blocks to fit a pattern. utterly oblivious of the fact that their left hand is following a few seconds behind, undoing all the good work. This much is well established. The dispute concerns the uniqueness of the kinds of tasks handled by the nvo hemispheres and how ffey go about it. In this regard, brain researchers have become more cautious in recent years while many pop psychologists have run wild. Using Sperry's techniques. researchers have confirmed that the left and right hemispheres are relatively better at different mental activities. Note. however, that we wrote relatively better. The two halves of the brain differ in how they process tasks rather than what they process (McCrone. 1999). Let's take language. for example. The left hemisphere is better at the specifics of speech, such as grammar and word generation, whereas the right hemisphere is better at the intonation and emphases of speech (what's known as "prosody"). Alåough the right hemisphere is better at nonlinguistic functions that involve complex visual and spatial processes, the left hemisphere plays some role in these capacities if we give it the chance. The light brain is better at dealing with a general sense of space, whereas corresponding areas in the left brain become active when die person locates objects in specific places. In many cases, it's not that one hemisphere or the other can't perform a given task; it's just that one of them can perform it faster and better than the other. So it tends to grab die assignment first. Of course, ordinary people aren't, as left brain/right-brain aficionados suggest, just split-brain patients who haven't gotten around to having their corpus callosums snipped. In the nonnal brain, the side that's first off the mark will call for help from across the way. As long as the left-right pathways are intact, the two hemispheres share information extensively. Indeed. brain imaging research shows that the two hemispheres routinely communicate during most tasks (Mercer, 2010). After a split-brain operation. this cooperation isn't possible, so the separated systems limp along as best ffey can. Therefore, the ways in which the two sides of brain differ are far more limited than pop psychology's "hemispheHcity" entrepreneurs suggest (Aamodt & Wang, 2008; Corballis, 1999, 2007; Della Sala, 1999). On balance. the two hemispheres are much more similar dian different in their functions (Geake, 2008). Modern neuroscientists have never agreed with many New Age "hemisphere trainers," who claim that the brain's two halves house totally dissimilar minds that approach the world in radically different ways, with one (the left) side an accountant and the other (die right) side a veritable Zen master. Robert Ornstein was among those to promote the idea of using different ways to tap into our "creative" right brains versus our intellectual left brains in his 1997 book, The Right Mind: MaEng Sense of the Hemispheres. Moreover, scores of educational and business programs de-emphasize getting die "right' answers on tests in favor of harnessing crati•ve abAity. Such programs as the Applied Creative Thinking Workshop have trained business managers to develop the untapped capacities of their right brains (Hermann.
1996). Furthermore, the enormously successful book. Drawing on the Right Side of the Brain (Edwards, 1980), which has sold over 2.5 million copies, encourages readers to unleash their artistic abilities by suppressing their "analytical" left hemispheres. Even cartoonists have jumped on the bandwagon; one shows a student holding an exam emblazoned with a big "F' who tells his professor, "It' s not fair to flunk me for being a right-brain thinker." The urge on the part of pop psychologists to assign all mental abilities to unique left and right compartments probably owes more to politics, social values, and commercial interests than to science. Its detractors have dubbed this extreme view "dichotomania" because of pop psychologists' tendency to dichotomize the two hemispheres' functions (Corballis, 1999). The notion was embraced enthusiastically by New Age proponents of the 1970s and 1980s, largely because it offered a rationale for world-views that were mystical and intuitive. hemisphere "logical," "linear," "analytical," and "masculine." In contrast, they proclaimed the allegedly warm and fuzzy right hemisphere "holistic," "intuitive," "artistic," "spontaneous," "creative," and "feminine" (Basil, 1988; Zimmer, 2009). Arguing that modem society undervalues the right hemisphere's touchy-feely mode of approaching the world, dichotomizers touted fanciful schemes for boosting this hemisphere's activity. Their books and seminars promised to free us of the barriers to personal growth imposed by an inflexible school system that favors "left hemisphere thinking." Yet an expert panel, assembled by the U.S. National Academy of Sciences, concluded that " . we have no direct evidence that differential hemispheric utilization can be trained" (Druckman & Swets, 1988, p. 110). The panel concluded that behavioral training could probably enhance different styles of learning or problem solving, but that such improvements were not due to differences in the two hemispheres' functioning. If the behavioral exercises promoted for right hemisphere calisthenics might yield a few benefits, we can't say the same for the far-fetched "brain tuners" sold for the same pumoses (Beyerstein, 1985, 1999a). Numerous devices of this sort allegedly harmonize or synchronize the activity of the two hemispheres. One of the most successful of these schemes was invented by a former public relations executive with no formal training in neuroscience. Like others of its ilk, the device supposedly synchronizes brain waves across the hemispheres by means of feedback signals. Probably because of the placebo effect (see Introduction, p. 14), the product found scores of satisfied customers. Yet even if the devices synchronized left-right brain waves, there's no reason to believe that making the two hemispheres resonate in this fashion would be good for us. In fact, if the brain is working optimally, this is probably exactly what you wouldn't w O Help Optimal psychological performance usually requires differential activation rather than synchronization of the hemispheres (Beyerstein, 1999a). The bottom line: Don't be taken in by the claims of dichotomizers with a seminar to sell or marketers of hemispheric synchronization gizmos that souiOd too good
The bottom line: Don't be taken in by the claims of dichotomizers with a seminar to sell or marketers of hemispheric synchronization gizmos that sound too good to be true. Current research on hemispheric differences, even by those responsible for discovering left—right specializations, focuses on showing how the normal works in an integrated fashion (Corballis, 2007; Gazzaniga, 1998; McCrone, 1999).
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