Unraveling the Mysteries of the Brain

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Ittakeslessthanhalfasecondto recognizeaface.Formostpeople,theprocessisinnate,yetothersstrugglewithit.TheysufferfromararebutsociallydebilitatingdiseasecalledProsopagnosia,orface-blindness. “It’slikealearningdisorder,buttheunderlyingbrainmechanismsareunclear,”saysKalanitGrill-Spector,anassistantprofessorofpsychologywholeadstheVisualPerceptionandNeuroscienceLabatStanford.Hermainresearchfocusisinunderstandinghowthehumanbrainrecognizesobjects—facesinparticular—andhowtheabilitydevelopsfromchildhoodtoadulthood. “Facesareaparticularlyinterestingstimulus,”shesays,explainingthatfacesareextremelysimilar,becausetheycontainthesamefeaturesandeveryone’seyes,nose,andmouthareroughlyinthesameplace.Yetmostofusarenaturallyabletodistinguishonepersonfromanotherinawaywecan’twithmanyotherobjects. Althoughneuroscientistsagreethatthereisaconstellationofregionsinthebrainthatprocessesobjectsandfaces,thereisdebateinthefieldonwhetherthereisauniqueregionthatspecializesonlyinprocessingfaces.Touncovertheanswertothismystery,Grill-Spectorandcolleaguesarelookingatthebrain’sintricatestructureusingfunctionalmagneticresonanceimaging,orfMRI. ThefMRImachineusesmagneticfieldstomeasurechangesinbloodoxygenationinthebraininresponsetoneuralactivity.Forexample,sayaresearchsubjectisshownapictureofHarrisonFord.Thepartofthebrainthatworkstorecognizetheactor’sfaceneedsoxygen,whichisdeliveredthroughthebloodstream.ThefMRIcandetectthechangesintheamountofoxygeninthebloodandthuscreateamapofwhereactivityisoccurringinthebrain.

SeveralresearchersinStanford’sDepartmentofPsychology,whichhasbeentop-rankednationallyfordecades,useimagingtechniquestoinvestigateadiversesetofunansweredquestionsaboutthebrain.AssistantProfessorofPsychologyBrianKnutsonandcollaboratorsinStanford’sGraduateSchoolofBusinessusefMRItolookatactivationintheportionsofthebrainlinkedtoexcitementandanxietyintheirstudiesonfinancialdecisionmaking.IanH.Gotlib,professorofpsychologyandseniorassociatedeanforthesocialsciences,examinesgeneticinformationandbrainresponsesinyoungwomentounderstandmechanismsthatincreasevulnerabilitytodepression.AndBrianWandell,theIsaacandMadelineSteinFamilyProfessorandchairofthepsychologydepartment,exploresthepathwaysthatareimportantinchildren’sbrainsastheylearntoread. “Eachoneofushassomethingwe’repassionateabout,”saysWandell,whoservesasco-chairofTheStanfordChallenge’sInitiativeonHumanHealth.Heisleadinganefforttocreateacampuscenterforcognitiveandneurobiologicalimagingwithcolleaguesfrompsychology,engineering,radiology,neurobiology,physics,andevenphilosophy.Thecenterwouldpromotesharingofinstrumentation,methodsforcomputationanddataanalysis,trainingcourses,andnewideasandknowledge.“OurgoalistomakeStanfordtheleaderinobtainingimagesandbuildingnewinstrumentstoobtainnewkindsofimages,”Wandellsays. MarkSchnitzer,assistantprofessorofbiologicalsciencesandappliedphysics,ispassionateaboutbuildingthoseinstruments.Hisresearchgrouphasdevelopedtheworld’ssmallesttwo-photonfluorescencemicroscope—adime-sizedapparatusthatcanrestonamouse’sheadandproducedetailedpicturesof

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A team led by Mark Schnitzer, assistant professor of biological sciences and applied physics, developed the world’s smallest two-photon fluorescence microscope, which is roughly the size of a dime.Photo:

Need caption copy for large photo.

componentsinitsbrain.Thetoolhaspotentialforbothbasicsciencestudiesofthebrainandclinicalapplicationslikeguidedsurgeries. Next,Schnitzerhopestobuildwhathecalls“theworld’slargestfluorescencemicroscope,”atoolthatwouldallowresearcherstoexaminehowgroupsofcellsinteractacrosstheentirespanofthebrain.Theenvisionedinstrumentwouldhelpresearchersseehowneuronsnetworkwitheachother,processinformation,andpassinformationtootherareas.Schnitzerbelievesthatakeyunansweredquestioninneuroscienceishowtheseprocessesultimatelyleadtobehaviors,andhehopeshismicroscopeswillhelpfindanswers.

Theface-recognitionstudiesperformedbyGrill-Spectorandcolleaguesalsopushthecuttingedgeofinstrumentation.SheworkswithphysicistsandengineerslikeGaryH.Glover,aprofessorinStanford’sradiologydepartmentwithcourtesyappointmentsinelectricalengineeringandpsychology,tomakeimprovementsinfMRImeasurementsandimagethevisualportionofthebrainwithhigherresolutionthaneverbefore.“Whenyouincreasetheresolution,”shesays,“aregionthatlooksveryhomogeneouswithstandardresolutionshowsmuchmoredetail.Thishelpsusmakemoreaccuratemeasurementsofbrainfunction.”

“Insights gained from Grill-Spector’s work shed light on disorders like autism, while other teams contribute knowledge of brain conditions such as dyslexia, depression, Alzheimer’s disease, and stroke.”

InsightsgainedfromGrill-Spector’sworkshedlightondisorderslikeautism,whileotherteamscontributeknowledgeofbrainconditionssuchasdyslexia,depression,Alzheimer’sdisease,andstroke.However,researchersarestillmostdrivenbybasicscienceandthechallengeofunravelingthebrain.AsSchnitzersays,“Tounderstandthebrainwouldbeamajorintellectualfeat.”

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