PROFILES. BRAIN GAMES. Tf)( Marro Polo of neuroscimcr. BY JOHN
COLAPINTO machandran's contribution to the field: "He is a continuation of a
tradition in.
PROFILES
BRAIN GAMES Tf)(Marro Polo ofneuroscimcr.
ne: morning in January, a tall, grnr Ohaired man whom I will call Arthur
Jamieson arrived 31 the Mandler Hall psychology building, at the University of California, San Diego, in La Jolla. J:lJ1'Iit5on is seventy)= old and IMs in the Midwest. H� is a physician and an amateur rellist, and has breo married for fony-seven }"an. 1-1e also suffers from a rare and bewildering condition calle d apotcmnophilia, the compukion to have a perfectly healthy limb amputarerl-in his C31lple started scotoma-a p«rticularly large blind spot publishing in this an:a ofhow specific de sometime; caused by a focaJlesion in the ''elopmcnts ofperceptual skilh OO\Ild be visual cortex. highly related," Braddick told mc:. In the mid-nineties, Gregory visited Ramachandran retumed to Madras 10 Ramachandran at V.C.S.D. toundertake complete his medical degree, and in the further experiments on scotoma, but they faIl of 1974 he enrolled at Trinity College were unable to find a patient "ith a focal to begin a Ph.D. in visual pelU)J!ion. "I lesion. Instead, they spent Gregory's thought they'd all be Uke Faraday aoo the weeklong \1s;t ;n\>estigating a phenome great Renaissance scientists,· he said of the non that had long fascinated Ramachan researchers he met in Englarxl. �Ninety dran: the reported ability of flounder to per cent ofthem are like Indian scientists, camouflage itself against p«lIu.KXI back or scientists here, for that matter, or any grounds.l.eading ichth�sts disagreed where---it's a nine-ro-fi\"cjob. They're not about whether the fish changed its ap ITIO\-ed by the great romantic spirit ofsci pearance orwhether the camouAage dfttt ence, and dley're not great Renaissance was art illusion. Ramachandran's local pet people. So I was a b it disillusioned.. Then STOre had no cold-water flounder, SO he I r a n into Richard Gregory bought fi,,, pcarockflouOOcr, a soon after I arrj,ro, and I said, related species that lives in 'Well, at \cast there's some of tropical coral reefs. The men plated the fuh on the bottom them here!' • Gregory was a professor of offoor small tankfbe phantoms, as he had shown, an: prot/lIctd in Ihe sensory rortcx,,vhcre nc:urons furthe faceha>t in vaded territOen though amputees no lon ger recehro these Signals from the non-
existent limb, Ramachandran bcliC."\...,d mat memories of these inputs remained in the nervous system and the brain. Reviewing the histories of amputees, Ramachandran noticed that many who suffered from cramping or clenching spasms had cxperienctd, before their am putations, a period during whlch thelimb was irnmobilizcd.. sometimes for months, in a sling or a cast. He thcorir.ed that a kind of"learned paralysis" was burned into the brnin's ciocull) i ', as repeated com mands ITorn the patients' brains to tTIO'.t the limb were met wim touch, visual, and nerve evidence that themb il could not move. When the limb was lat�,. ampu tall'd, the patient was stuckwith a revised body-im"S" map, which indudo::l a pna Iprophantom wlx« nturalpathways re tained a tlll"mOl)'ofpainsignals that could not beshut of[ Ramachandran wondered what would happen ifIl.Ich a patient 'vas presented,vith cvidcrx:r that thephantom could 1110\..., ("I sec my hand reaching for theU1pi. Ifthe brain couldbe tricked imo minking that the phantom 'vas moving. woold thecramping genSatlonS cease? I lis firot test subject was a ywng man who a decade earlier had crashed his mo torg:cle and torn from his spinal column the nerves supplying his left ann. After keeping the useless amI in a sling for a year, the man had the ami amputated above the dhow. Ever sioa:, he had felt unremitting cramping n i the phantom limb, as though itwen: immobilized in an awkward position. In his office n i Mandler J-laU, Ra machandnm positioned a twenty-inch by-twenty-inch drugstore mirror up right, and perpendicular to the man's body, and told him to place his intact right ann on One side of the mirror and his stump on the other. He told the man to ammge themirror SO that the tclkction created the illusion that his intact arm was the continuation of the amputated one. Then Ramachandran asked the man to mm..., his right and left arms si multaneously, in synchroll()l.ll; motions like a oondoctor-while keeping hi!; eyes Of} the rdlection ofhis intact ann. "Oh, l1ly God!" the man began to shout. "Oh, my God, Doctor, this is unbelievable." For the first tinlC in ten)...,ars, thepatient could feel his phantom lil1lb "moving," and the cramping pain was instantly relieved. After the man had used the l1lirror therapy ten minutes a day (or a
month, his phantom limb shrank-"the first example in medical history," Ra machandran latcr wrotc, "of a successful 'ampuration' ofa phantom limb." Ramachandran conducted the experi ment on eight other am?Jt.llts inNatllrt, in 1995. In all but one JXlticnt, phantom lllillds that h:J.d been balled into prunful fists opened, aOO phantom arms that had stiffened into as onizingromortions st�>htcncd. "hoople ahvays ask, 'How did you think of the mirror?" Ramachandran told me. And I say, 1 don't know!' Then: was a mirror in the lab, so that must have been in my mind, and I said, 'Let's tIy it.' It's not any more m}Sttrious than f i you say SOme •
members with lower-limb ampuratiolls, in which six were gi\'Cll mirror thempy and the o,d,,,, othersWI.'TC e-. .. " ly dividcd !xo",-'Cn ow control therapies (aCO\'Cred mirror and menta! visuali2.atinn), the six who used the mirror reported that their JXlin dccrcascd {and, n i some cases, dis appcan:d altogcth�'f). ln the t\w contro1 groups, onlythree patients reported pain relief, and others found that their pain inrn:ascd. Tsao published his results n i
the N= Eng/andjo"",,,!0/Mmici,,�, in 2007. "Tbe people who R-ally got com pletely pain-free remain so, t\vo years Iatcr," said Tsao, who is curremly con ducting a study in\'olving mirror therapy
on uppcr-limb amputccS atWalter Rroi
thing 'poppt.d into' }"'Ote ....,ad Ramachandran's Na/urt paper on himsclfto l"'-"urology. "Visionwas gl,."ttlng mirror therapy for phantom-limb pain. ovcrcrowI;kd," he told me. Neurology "' said, '\Vhy the m.."ck:should this work? SCI..'Il1
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dets, including the Capgras delusion, in ,vhich an othcnvisc lucid victim of a head injuty insists that close lQ\m ones (spouses, JXlrcnts, children) are impos tors. Freudians had theorized that Capgras patients\\IC1C sufferingfrom un bearable OcdiJXII desires aroused by the blow to the head, but Ramachandran demonstrated that SC\�'TCd ncural JXlth w�}Sbct\>'CCIl the facial-recognition areas of the visual rorrcx and the emotional C\:nters ofthe brain ,,,,-'TC I"CSJXl'"lsiblc fix the disorder. He also m i utigatcd post stroke syndromes, n i which patients deny that � paralyuxl limb has bocomc immo bile or, in a more SC\"CI"e ,.ersion, insist that the paralyzed arm or leg bclongs to somcooc
clsc. Ramachandran traced the
delusion to �'" in the �>ht superior
parieral lobulc, the body-map region, whe...., the di=cpancy bctWl,.'Cll the ab sence ofsignals &om thelimb to thebrain and the prcs.:nce oftk limb on the body results in a dcf�'fIS;"'e rationalization that the arm orkg must be someone else's. A few years ago, Ramachandran began studying apotcmnophUia, the romp\lt sion to amputate a healthylimb. He is, he said, "niocty-fi\'C per cent sure" that he has figun:d oot the cause ofthe disorder. His consultation with Anhur Jamieson strengthened tlUs conviction. Mter intervie\ving Jamieson n i his offihthaOO using a Velcro $tr.Ip.TIx: s('."nsor""; (for inspiration); SC11."ral plastic is, i�s a minefield," he told tnC. "!be par minimizing lenses (Ramachandran has ,
ents arc involved. There's big money in volved. Suppose }"OI' imuted your life in salingthat the ccrcbellum iswhat'sgoing on, tILT! somcone comesaIongandspends onc };m Wa!; damaged, the sub consciousmovement of the vocal (Ords could be interpreted a!; an oot!;ide ''Giee speaking in one's head, "By tho: way," Ramach�ndran contin ued,"] ha\'e a theory that f i you take pe0ple with cudnoma ofthe larynx, mel }UU fCf1l{)\'e the: \'(:01 cords, and they think to thermd\'ts, they may actually start haUu einating. A prediction: '1lUs remark prompted Laura Case, a first-year graduate student who has fo russaI on autism., tn speak. "lll:lt could be interesting in autism, too," Case said. "Btxaust ifthey lacktil!: robust mirror ac tivaOOn for actions, which they do-' Ramachandran interjected, tnen they cnofure--so t:hLy may cnnfusc their own voca1izations with somebody else's! And peopk hav" linked autism toschizo. phrenia. 1be old throry ,vas that it ,vas carly-
