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Title:BiologicalApproach2.1LocalizationofBrainFunctionKeyQuestion:Howaredifferentpartsofthebrainresponsiblefordifferentbehaviours?WHATYOUNEEDTOKNOWYouwillneedtobeabletodothefollowing:1. Explainoneresearchstudyintolocalizationofbrainfunction.

a. Study:Maguireetal(2000)–hypothalamusandspatialmemoryIntroductionLocalizationofbrainfunctionreferstothetheorythatdifferentpartsofthebrainareresponsible for different aspects of human functioning, such as behaviours. Thisrelatesdirectlytotheassumptionofthebiologicalapproachthatcognitions,emotionsand behaviours are products of the anatomy andphysiology of ournervous andendocrine systems.LocalizationofbrainfunctionPsychologistsinvestigatinglocalizationofbrainfunctionfromthebiologicalapproachuse brain-imaging techniques to investigate the correlation (relationship) betweenbrain processes and structures and human behaviour. Before thesewere available,psychologists used post-mortem examination of the brains of people with certainproblems, inordertotryandfinddamagethatcorrelatedwiththeproblem,suchaslackofspeechoramnesia.Forexample,Broca(1861)discoveredoneoftheimportantareas in the brain that is responsible for speech, now called “Broca’s area”. Hediscovered thisbyperforminganautopsyonapatientwhohad thenickname“Tan”because of his inability to say anything other than this sound. At the post-mortemexamination,abnormalitieswerefoundinthisregionofthepatient’sbrain,suggestingthat this wasresponsible for hisaphasia. However,although post-mortem investigationis sometimes stillused, it is now moreusual to use MRI,fMRIor PET scans toresearch thecorrelation betweena particular part ofthe brain and humanbehaviour.

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KeyStudy7:Maguireetal.(2000)Aim:Toexaminewhetherstructuralchangescouldbedetectedinthebrainofpeoplewithextensiveexperienceofspatialnavigation.Method:StructuralMRIscanswereobtainedfrom16right-handedmaleLondontaxidrivers who had been driving for more than 1.5 years. The MRI scans of 50 right-handedmaleswhodidnotdrivetaxiswereincludedforcomparison.Themeanagedidnotdifferbetweenthetwogroups.Results:1) Increased greymatterwas found in the brains of taxi drivers, comparedwithcontrols,intwobrainregions,therightandlefthippocampi.Themajorityoftheincreasedvolumewasfoundintherightposterior(rear)hippocampus.2)Changeswithnavigationexperience–acorrelationwasfoundbetweentheamountoftimespentasataxidriverwithvolumeintherightposteriorhippocampus.Conclusion: The results provide evidence for structural differences between thehippocampi of London taxi drivers andcontrol participants. Therefore, theenvironment (driving a taxi in London,atatimewhenaGPSwasnotused,anddrivershadtomemorisethelocationofall the streets) affected the brainstructure.This is evidence of localization offunction – as it suggests that spatialmemory is located in the posteriorhippocampus. It is also evidence ofbrain plasticity, as the hippocampusclearly changed in response to theenvironment(seeSection2b).EvaluationStrengths:Manyextraneousvariablesarecontrolled: themeanage, thehandednessandthegenderofthetwogroupswerethesame.However,theresultsonlyshowacorrelation:itispossiblethatpeoplewithlargerthannormalposteriorhippocampiareattractedtocareersthatusetheirspatialabilities, includingtaxidriving.Butthefactthat therewas apositive correlation between the number of years spent as a taxidriverand thevolume in the rightposteriorhippocampuswould tend tocounteractthis argument. The researchers were also careful to only choose brain scans fromhealthynon-taxidriversasacontrolgroup.Limitations: TheMRI scans of these non-taxi drivers were obtained from a Londonhospital,whichraisesethicalissuesregardinginformedconsentanduseofdata.

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CriticalThinkingPointsWhataboutthesmallsamplesizeandthegenderoftheparticipants?Wouldthesameresultshavebeenfoundwithwomentaxidrivers?Sixteenpeoplearenotmanyfromwhichtodevelopatheoryregardingspatiallearningandtheposteriorhippocampus.PossibleExamQuestionsShortanswerquestion1. Explainonestudyinvestigatinglocalizationofbrainfunction.(Remember for this answer, youwill need to say exactly howMaguire et al’s studydemonstratedlocalizationofbrainfunction).

Essayquestions2. Discusshowpsychologistsinvestigatelocalizationofbrainfunction,usingrelevant

researchtosupportyouranswer.(Morethanonestudywouldbeneededforthisanswer,butMaguireetalwouldbeagoodstudytouse).