Download 31:001 Elementary Psychology Fall 2016 Professor Vecera Brain

31:001
ElementaryPsychologyFall2016
ProfessorVecera
Brain&Behavior1:Einstein’sbrain
I.WhatMakesUsSmart?
A.Einstein’sbrain:Usedtoanswerthisquestion.Nostraightforwardanswer,though.
Einstein’sbrainshowedsomedifferencesinoneregion,butnotmuchelse.Although“gross”
neuroanatomydifferslittle,itdependsonwhereyoulook.
B.Threemajordivisionsofthebrain:Therearethreemaindivisions,butit’sthelastofthese,
theforebrain,thatsetshighermammalsapartfromotheranimals.It’salsowhatprobably
madeEinsteindifferent.
Threemajordivisionsofthebrain.Theseareverycoarsestructures,andeachoneofthemis
composedofmanyparts.
1.Thehindbrain:Thisisthelowestsetofstructuresinthebrain.Thinkofthisasyourreptilian
brainbecausemanyofthestructuresdothesamethinginhumansthattheydoinreptiles.
2.Themidbrain:Nextupthehierarchyofthebrainisthemidbrainregion.Thisisourbirdand
amphibianbrainbecauseit’ssimilarinhumansandamphibians.
3.Theforebrain:Finally,wehavetheforebrain.Thisisahugeregionofbrainthatincludesthe
cerebralcortex,plusseveralsubcorticalareas.(Subcorticalmeans“belowthecortex.”These
arestructuresthatarebelowthegraymatterofthecortex.)
II.AFewPartsofForebrain
A.BasalGanglia:Importantformovement(thisistheregionthathasdepleteddopaminein
Parkinson’sdisease)
B.LimbicSystem:Asetofstructuresimportantforemotionaswellaslearningandmemory
C.CerebralCortex:Whyisthecortexwrinkled?Lobes;occipital,parietal,temporal,frontal
III.NeuropsychologyofCortex
We’llinvestigatethepsychologicalfunctionssupportedbyeachofthelobes.Theideahereis
thatpsychologicalbehaviorscanbelocalized—pinpointedto—differentregionsofthecortex.
(But,weshouldn’toversimplifylocalizationoffunction.Complexbehaviorsrequiremanyareas
workingtogether.)
IV.HowCortexWorks
Inunderstandingwhatmakesussmart,wealsoneedtolookbeyondlargebrainregions(“gross
anatomy”).Weneedtoconsiderhowthoselittleneuronsarewired—howthey’reconnected
withoneanother.
Oneconsequenceofwiringisthatmapsarecreatedinthebrainfordifferentsystems.We’ll
talkabouttouchandthesomatosensoryhomunculus.Therearetwokeypointstothis
homunculus:1.Adjacentpointsontheskinsurfaceremainadjacentincortexand2.Some
regionsoftheskinsurfacehavemorecortexdevotedtothem(e.g.,hands,lips).
Onethingweseewithcortexisthatitisplastic(i.e.,malleable).Intouch,weseethisinthe
changesinthehomunculusfollowingamputation.But,thisplasticityhassomelimitations,asis
evidentinphantomlimbpainandthephantomlimbsyndromethatcanfollowamputationofa
limb.
Termsusedinthislecture
hippocampus
amygdala
cerebralcortex/cerebralhemispheres
occipitallobe
parietallobe
temporallobe
frontallobe
agnosia:impairmentinobjectrecognition
aphasia:impairmentinlanguage
amnesia:impairmentinmemory
PhineasGage(thenameofapersonwe’lltalkabout)
Somatosensoryhomunculus