Smart Brain. We all know someone who is not. What Does a. Look Like? SPECIAL SECTION INTELLIGENCE. By Richard J. Haier

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1 SPECIAL SECTION INTELLIGENCE What Doe a Smart Brain Look Like? By Rihard J. Haier We all know omeone who i not a mart a we are and omeone who i marter. At the ame time, we all know people who are better or wore than we are in a partiular area or tak, ay, rememberin fat or performin rapid mental math alulation. Thee variation in abilitie and talent preumably arie from differene amon our brain, and many tudie have linked ertain very peifi tak with erebral ativity in loalized area. Anwer about how the brain a a whole interate ativity amon area, however, have proved eluive. Jut what doe a mart brain look like? Now, for the firt time, intelliene reearher are beinnin to put toether a bier piture. Imain tudie are unoverin lue to how neural truture and funtion ive rie to individual differene in intelliene. The reult o far are onfirmin a view many expert have had for deade: not all brain work in the ame way. People with the ame IQ may olve a problem with A ARON GOODMAN (photoillutration); PA SIEK A /SPL /PHOTO RE SE ARCHERS, INC. (brain imae ) 26 SCIENTIFIC AMERICAN MIND November/Deember 2009

2 A new neuroiene of intelliene i revealin that not all brain work in the ame way SPECIAL SECTION INTELLIGENCE w w w. SientifiAmerian.om/Mind SCIENTIFIC AMERICAN MIND 27

3 SPECIAL SECTION INTELLIGENCE A entury of peniland-paper tetin revealed how mental abilitie an be aeed, but how intelliene arie from brain truture and funtion i only now bein unovered with neuroimain. equal peed and auray, uin a different ombination of brain area. [For more on IQ and intelliene, ee Rational and Irrational Thouht: The Thinkin That IQ Tet Mi, by Keith E. Stanovih, on pae 34.] Men and women how roup averae differene on neuroimain meaure, a do older and youner roup, even at the ame level of intelliene. But newer tudie are demontratin that individual differene in brain truture and funtion, a they relate to intelliene, are key and the latet tudie FAST FACTS Smart Brain Revealed 1>> have expoed only the tip of the ieber. Thee tudie hint at a new definition of intelliene, baed on the ize of ertain brain area and the effiieny of information flow amon them. Even more tantalizin, brain an oon may be able to reveal an individual aptitude for ertain aademi ubjet or job, enablin aurate and ueful eduation and areer ounelin. A we learn more about intelliene, we will better undertand how to help individual fulfill or perhap enhane their intelletual potential and ue. Brain truture and metaboli effiieny may underlie individual differene in intelliene, and imain reearh i pinpointin whih reion are key player. 2>> 3>> Smart brain work in many different way. Women and men who have the ame IQ how different underlyin brain arhiteture. The latet reearh uet that an individual pattern of ray and white matter miht underlie hi or her peifi onitive trenth and weaknee. For 100 year intelliene reearh relied on penil-and-paper tetin for metri uh a IQ. Pyholoit ued tatitial method to haraterize the different omponent of intelliene and how they hane over people lifetime. They determined that virtually all tet of mental ability, irrepetive of ontent, are poitively related to one another that i, thoe who ore hih on one tet tend to ore hih on the other. Thi fat implie that all tet hare a ommon fator, whih wa dubbed, a eneral fator of intelliene. The fator i a powerful preditor of ue and i the fou of many tudie. [For more on, ee Solvin the IQ Puzzle, by Jame R. Flynn; Sientifi Amerian Mind, Otober/November 2007.] In addition to the fator, pyholoit alo have etablihed other primary omponent of intelliene, inludin patial, numerial and verbal fator, reaonin abilitie known a fluid intelliene, and knowlede of fatual information, alled rytallized intelliene. But the brain mehanim and truture underlyin and the other fator ould not be inferred from tet ore or even individual with brain damae and thu remained hidden. PAUL THOMAS Getty Imae 28 SCIENTIFIC AMERICAN MIND November/Deember 2009

4 COUR TESY OF R ACHAEL GRAZIOPLENE (top); SCIENTIFIC AMERICAN MIND; SOURCE: R. E. JUNG ET AL. IN NEUROIMAGE, VOL. 26, NO. 3; 2005 (bot tom) The advent of neuroiene tehnique about 20 year ao finally offered a way forward. New method, partiularly neuroimain, now allow a different approah to definin intelliene baed on phyial propertie of the brain. In 1988 my olleaue and I at the Univerity of California, Irvine, onduted one of the firt tudie to ue uh tehnique. Uin poitron-emiion tomoraphy (PET), whih produe imae of metabolim in the brain by detetin the amount of low-level radioative luoe ued by neuron a they fire, we traed the brain enery ue while a mall ample of volunteer olved nonverbal abtrat reaonin problem on a tet alled the Raven Advaned Proreive Matrie [ee illutration at riht]. Thi tet i known to be a ood indiator of, o we were hopin to anwer the quetion of where eneral intelliene arie in the brain by determinin Gray matter White matter Men whih area howed inreaed ativation while olvin the tet problem. To our urprie, reater enery ue (that i, inreaed luoe metabolim) wa aoiated with poorer tet performane. Smarter people were uin le enery to olve the problem their brain were more effiient. The next obviou quetion wa Whih of the eiht option orretly omplete the matrix? Thi type of abtrat reaonin problem i imilar to thoe on the Raven tet, a ood indiator of eneral intelliene. (The anwer i number 7.) whether enery effiieny an arie throuh pratie. In 1992 we ued PET before and after ubjet learned the omputer ame Tetri (a fat paed viuopatial puzzle), and we found le enery ue in everal brain area after 50 Women The trutural root of intelliene may differ by ender. In women hiher IQ ore are aoiated with more ray and white matter in frontal lanuae area, wherea in men hiher IQ orrelate with more ray matter in poterior enory interation area. day of pratie and inreaed kill. The data uet that over time the brain learn what area are not neeary for better performane, and ativity in thoe area diminihe leadin to reater overall effiieny. Moreover, the individual in the tudy with hih howed more brain effiieny after pratie than the people with lower. By the mid-1990 we were fouin on effiieny a a key onept for undertandin intelliene. But then, in 1995, we diovered a differene in the way male and female brain work, ivin u our firt lue to what we know today: the onept of effiieny depend on the type and diffiulty of tak involved, and there are individual and roup differene in brain funtion durin problem olvin, dependin on who i doin the thinkin. In the 1995 tudy we teted a peifi mental ability mathematial reaonin. We eleted ollee tudent with either very hih or averae SAT-Math ore and ued PET to invetiate their brain funtion while they olved mathematial reaonin problem. Unlike the tudie, thi tudy howed the people with hih math ability uin more brain enery in a ertain reion (the temporal lobe), but thi wa true only for the men and not for the women even thouh both men and women performed at the ame level on the tet. Gender Matter Thee obervation have now been repliated by u and other reearher, epeially in tudie uin advaned eletroenephaloraphi (EEG) mappin tehnique. In addition to thee experiment howin differene in brain funtion, brain truture alo eem to play a role tudie have ueted that other ender differene in onition, uh a the tendeny for men to have better viuopatial ability, may be rooted in arhiteture. For example, in a erie of paper publihed in NeuroImae tartin in 2004, we ued trutural MRI an to invetiate orrelation between ray and white matter volume and ore on intelliene tet. Gray matter, made up of neuron ell bodie, doe the omputa- (The Author) RICHARD J. HAIER i profeor emeritu in the Shool of Mediine at the Univerity of California, Irvine. w w w. SientifiAmerian.om/Mind SCIENTIFIC AMERICAN MIND 29

5 SPECIAL SECTION INTELLIGENCE The Neural Root of Intelliene Loated on the medial urfae (between hemiphere) Frontal lobe Brain-imain tudie reveal many area in whih the amount of ray matter (neuron bodie) orrelate with intelliene tet ore. The olor pathe above indiate the approximate loation of the Brodmann area trutural roupin of neuron numbered aordin to hitorial tradition. The letter on eah Brodmann area indiate whih intelliene fator it i aoiated with: eneral (); patial (); and rytallized (), or fatual knowlede. Every individual ha a unique pattern of ray matter in thee area [ee raph on oppoite pae], ivin rie to different onitive trenth and weaknee. tional work of the brain. White matter enable ommuniation amon reion of ray matter via axon, brain ell lon, wirelike appendae. Our tudie point to a network of area ditributed throuhout the brain where more ray or white matter i related to hiher IQ ore. The peifi area in thi network are different in men and women, uetin there are at leat two different brain arhiteture that produe equivalent performane on IQ tet. In eneral, we found that in women more ray and white matter in frontal brain area, epeially thoe aoiated with lanuae, wa orrelated ,2, Parietal lobe Fourteen of the Brodmann area (olored orane above) are onitently impliated in tudie of intelliene-related brain truture and funtion. Neuropyholoit Rex E. Jun of the Univerity of New Mexio and I reviewed the tudie and identified thi network, allin it the parieto-frontal interation theory (P-FIT) beaue area in the parietal (reen) and frontal (blue) lobe were onitent aro the mot tudie. Mot of the P-FIT area are involved in omputation (frontal area) and enory interation (parietal area), the proein and oniou undertandin of enory information. R.J.H. Key Brodmann area (trutural roup of neuron) Brodmann area impliated in parieto-frontal interation theory of intelliene General intelliene Crytallized intelliene (fat) Spatial intelliene with IQ ore; in men IQ ore orrelated with ray matter in frontal area and, epeially, in poterior area that interate enory information [ee bottom illutration on preedin pae]. Children alo how different developmental brain pattern related to IQ, dependin on their ender. In a erie of imain tudie with lare ample, publihed from 2006 to 2008, neuroientit Vinent J. Shmithort of the Cininnati Children Hopital Medial Center and hi olleaue found that a irl ae they how inreain oranization that i, well-defined path between diparate brain reion in their riht hemiphere. Boy, in ontrat, how thi developmental trend in their left hemiphere. We do not yet know how thee findin relate to behavioral or learnin differene, but the reearh point the way for future tudie to determine how brain development relate to boy and irl onition and aademi ahievement. [For more on ender differene, ee Sex, Math, and Sientifi Ahievement, by Diane F. Halpern, Camilla P. Benbow, David C. Geary, Ruben C. Gur, Janet Shibley Hyde and Morton Ann Gernbaher; SCIENTIFIC AMERICAN MIND; SOURCES: R. E. JUNG AND R. J. HAIER IN BEHAVIORAL AND BRAIN SCIENCES, VOL. 30, NO. 2; 2007, AND K. MARTÍNEZ AND R. COLOM IN PERSONALIT Y AND INDIVIDUAL DIFFERENCES, VOL. 46; SCIENTIFIC AMERICAN MIND November/Deember 2009

6 Sientifi Amerian Mind, Deember 2007/January 2008.] A New Definition Gender differene were merely the firt indiation that not all brain work the ame way. In 2003 we invetiated whether we ould oberve funtional variation durin paive mental ativity without a tak ained. Aain we ued PET in two roup of volunteer eleted for hih or averae ore on the Raven tet. Both roup wathed the ame video paively with no problem olvin or other tak demand. The roup with hih tet ore howed different brain ativation in poterior viual-proein area a ompared with the averae roup. The data uet that early tae of information proein are more enaed in individual with hiher intelliene, perhap uetin that the marter people in the tudy were not wathin the video paively after all they were atively proein what they were eein. Gray Matter Volume Peron 1 Peron 2 Peron 3 primary loation for intelliene. In partiular, part of the parietal lobe, loated under the rown of the head and known to be involved in enory interation, play a inifiant role. Beaue ar- How Brain Stak Up LBA47 LBA18 LBA21 LBA10 LBA19 RBA39 RBA9 RBA10 Left and Riht Brodmann Area (brain truture) Averae of 100-peron roup Brain profile of three individual how the amount of ray matter eah ha in area aoiated with intelliene, alled P-FIT area [for more information about thee brain area, ee box on oppoite pae]. The peron who ored the hihet in the 100-peron tudy roup on tet of eneral intelliene, or, ha far more than the roup averae amount of ray matter in every area (blue line). The other two individual (red and orane line) had idential, averae ore, but their pattern of ray matter differ. Further reearh ould reveal how uh differene orrepond to an individual onitive trenth and weaknee. ty wa epeially aoiated with IQ ore. The findin upport the idea that eneral intelliene not only arie from ray matter volume but alo depend to a lare extent on the white Every individual ue ome ombination of intelliene-related brain area in a unique way. SCIENTIFIC AMERICAN MIND; SOURCE: COUR TESY OF RICHARD J. HAIER Althouh more and more evidene how that problem olvin and even paive enory proein doe not look exatly the ame in every brain, we till are able to identify a network of area that eem to ive rie to intelliene in eneral. In fat, definin the ruial reion and onnetion will help u delineate exatly how eah peron brain work every individual ue ome ombination of thee area in a unique way. In 2007 neuropyholoit Rex E. Jun of the Univerity of New Mexio and I reviewed the 37 neuroimain tudie on intelliene that exited at that point. In the journal Behavioral and Brain Siene, we identified alient brain area found in both trutural and funtional tudie with ome oniteny. The 14 area are ditributed throuhout the brain, refutin the lon-held notion that the frontal lobe alone are the ea in the parietal and frontal lobe were mot repreented aro the tudie we reviewed, we alled our theory of intelliene baed on thi network the parieto-frontal interation theory (P-FIT). The 14 P-FIT area are involved in attention, memory, lanuae and enory proein [ee box on oppoite pae]. Identifyin the P-FIT network implie a new definition of eneral intelliene baed on the brain meaurable harateriti. Both the amount of ray matter in ertain P-FIT area and the rate of information flow amon thee area are likely to play key role in intelliene. Earlier thi year tudie at Univerity Medial Center Utreht in the Netherland and the Chinee Aademy of Siene in Beijin ued funtional MRI to determine the effiieny of onnetion throuhout the brain, pinpointin P-FIT area where onnetivi- matter onnetion between ruial ray matter area. More effiient onnetion allow information to flow fater and quik proein time eem to o hand in hand with a hih IQ. Everyone I Unique But IQ ore do not tell the whole tory not even loe. Intelliene eem to arie from varyin ombination of the P-FIT brain area in different people, whih may explain eah peron individual trenth and weaknee. The hallene of identifyin thee pattern are well illutrated by the extremely rare ae of autiti avant. Daniel Tammet, for example, i an autiti youn adult with unommonly hih IQ ore. He ee number a olor and hape, whih allowed him to memorize the value of pi to 22,514 diit. He alo learned to onvere fluently in Ielandi after only ev- w w w. SientifiAmerian.om/Mind SCIENTIFIC AMERICAN MIND 31

7 SPECIAL SECTION INTELLIGENCE en day of intrution. Tammet lead an independent life and wrote a bet-ellin autobioraphy deribin hi extraordinary numerial and lanuae ability. What would hi brain profile how? [For more on Daniel Tammet, ee Think Better: Tip from a Savant, by Jonah Lehrer; Sientifi Amerian Mind, April/May/June 2009.] Althouh we are not urrently able to dedue from a an of Tammet brain other peifi intelliene fator. For detail of whih area are onneted to eah fator, ee the box on pae 30. One of the mot tantalizin idea to ome out of thi reent reearh i the poibility of mathin an individual ray and white matter pattern to hi or her and to other peifi intelliene fator. In other word, the tiue in P-FIT area may predit a peron unique pattern of onitive trenth and weaknee aro a rane of mental abilitie. Thee differin brain profile may explain why two people with an idential IQ ore may how very different onitive abilitie. The data from Madrid illutrate thi idea niely [ee illutration on preedin pae]. The peron in our volunteer roup with the hihet ore howed far more ray matter than the roup averae amount in everal P-FIT area perhap not urpriinly. But it i interetin to note that two people with idential ore of 100, the averae for the roup teted in the tudy, exhibited different onitive profile, uetin different onitive trenth and weaknee. The idea that we all have our own pattern of variation in brain area that ontribute to different intelliene fator i underored dramatially by a trutural MRI tudy in Marh of 241 patient with brain leion. Pyholoit Jan Gläher of the California Intitute A learnin proram ould be tailored baed on an individual tudent brain harateriti. how hi extraordinary abilitie arie, the mot reent wave of neuroimain tudie ha iven u lue to how we miht one day do exatly that. New tudie have found orrelation between ray matter in ertain area and peifi intelliene fator. In Marh pyholoit Roberto Colom of the Autonomou Univerity of Madrid and hi ollaborator (inludin me) reported on the relation between ray matter volume and different intelliene fator in 100 youn adult. Eah peron ompleted a battery of nine onitive tet known to indiate different intelliene fator, inludin, fluid intelliene, rytallized intelliene and a patial fator. We found a poitive orrelation between ore on the fator and the amount of ray matter in everal area predited by P-FIT. And one we aounted for the ommon fator, we found that ray matter volume in ertain brain area wa related to the Brain an may oon be able to profile an individual trenth and weaknee. Suh onitive profile ould be valuable for eduation and areer ounelin. of Tehnoloy and hi olleaue howed that the ite of eah leion wa orrelated with peifi fator ore. For example, pereptual oranization uffered patient had trouble oniouly undertandin raw information from their ene when their riht parietal lobe wa damaed. A Smarter Future Thee mot reent tudie uet that neuroimain ould one day beome a upplement or even a ubtitute for traditional paper-and-penil intelliene tetin. An individual brain profile ould be valuable. In eduation, for example, a learnin proram ould be tailored for an individual tudent, at any ae, baed on that tudent brain harateriti. Perhap voational ue ould alo be predited are there pattern of ray matter aro ome area, for example, that make for the bet teaher, fihter pilot, enineer or tenni player? People eekin a better life with voational and areer onultation ertainly will want the hoie of havin a brain aement if there are data to upport it uefulne. But it i worth rememberin that, ontrary to older doma, BURAK PEK AKCAN istokphoto (thouht bubble); GE T T Y IMAGES (baketball ); SHARON DOMINICK istokphoto (book and mor tarboard ) 32 SCIENTIFIC AMERICAN MIND November/Deember 2009

8 Bootin Healthy Brain The latet reearh into the neural root of intelliene may lead to better dru and tool for onitive enhanement. In the future, dru may enhane the neurotranmitter that reulate ommuniation amon the alient brain area underlyin eneral intelliene or more peifi mental abilitie. Other dru ould timulate ray matter rowth or white matter interity in relevant area. Certainly uh advane would be welome a potential treatment for mental retardation and developmental diabilitie. They may alo be welome by any individual lookin for more intelliene. If an effetive IQ pill beome available, are the oietal and ethial iue the ame a for performane-enhanin dru in port, or i there a moral imperative that more intelliene i alway better than le? Apparently, many ientit aree with the latter. An online urvey of 1,427 ientit onduted in 2008 by Nature found that 20 perent of repondent already ue preription dru to enhane onentration rather than for treatin a medial ondition. Almot 70 perent of 1,258 repondent who anwered the quetion aid they would be willin to rik mild ide effet to boot their brainpower by takin onition-enhanin dru. Eihty perent of all the ientit who reponded even thoe who did not ue thee dru defended the riht of healthy human to take them a work booter, and more than half aid their ue hould not be retrited, even for univerity entrane exam. More than a third aid that they would feel preure to ive their hildren uh dru if they knew other kid at hool were alo takin them. Few appear to favor the inorane i bli poition. Intelliene i a ritial reoure for the development of ivilization. A the lobal eonomy evolve and mall ountrie ompete with larer ountrie, aein, developin and even enhanin intelletual talent may well beome the neuroiene hallene for the 21t entury. R.J.H. EQUINOX GRAPHICS/SCIENCE PHOTO LIBRARY the brain i not et in tone or in eneti immutability. Exatly the oppoite i true. The brain i plati it hane. A brain profile detailin a peron trenth would offer a uide rather than a preription perhap uetin way to pratie kill or improve eduation o that a peron ould beome better uited for the ativitie or areer he or he i mot intereted in. Fainatin reent tudie how that learnin to jule inreae the amount of ray matter in brain area relevant to motor ativity. When the trainin top, the additional ray matter diappear. Beaue reional ray matter i related to intelliene, an trainin beyond onventional eduation approahe be direted at peifi brain area to inreae intelliene? We do not yet know, but the propet i exitin. The next phae of neurointelliene reearh may inlude tudie deined to anwer uh quetion, inludin eduation experiment to determine whether different trateie produe peifi brain hane and whether tudent eleted on the bai of their individual (Further Readin) brain harateriti are more likely to maximize learnin in a partiular ubjet with one eduational tratey veru another. The oal would be to enhane urrent eduational deiion makin by addin utomized information about eah tudent brain. How any peifi brain harateriti develop and how it may be influened are ritial, but eparate, quetion for reearh. Whether everyone aree on preiely the ame definition of intelliene or not, prore in neuroiene i inexorable. We will ontinue to diover how the brain manae the omplex information proein that undoubtedly underlie all notion of intelliene. Given the ravae of brain dieae, ain, the tehnial need of modern oietie, the hallene of eduation and the joy of experienin the world throuh intellet, there i ome ureny to undertand how mart brain work. It i not too early for diuion about the impliation of the earh for neurointelliene and our willinne to o where the data lead. M Why Aren t More Women in Siene? Stephen J. Cei and Wendy M. William. Amerian Pyholoial Aoiation, The Parieto-Frontal Interation Theory (P-FIT) of Intelliene: Converin Neuroimain Evidene. Rex E. Jun and Rihard J. Haier in Behavioral and Brain Siene, Vol. 30, No. 2, pae ; Brain Imain Studie of Intelliene and Creativity: What I the Piture for Eduation? Rex E. Jun and Rihard J. Haier in Roeper Review, Vol. 30, No. 3, pae ; Gray Matter Correlate of Fluid, Crytallized, and Spatial Intelliene: Tetin the P-FIT Model. Roberto Colom, Rihard J. Haier, Kevin Head, Juan Álvarez-Linera, María Ánele Quiroa, Pei Chun Shih and Rex E. Jun in Intelliene, Vol. 37, No. 2, pae ; Marh-April w w w. SientifiAmerian.om/Mind SCIENTIFIC AMERICAN MIND 33