AP-psychology总结Unit3

Chapter3BiologicalBasesofBehaviorNeuroanatomyNeuroanatomythestudyofthepartsandfunctionofneuron(individualcellnerves)NeuronStructure：1.Dendrites:rootlikepartsofthecellthatstretchoutfromthecellbody.2.Cellbody/thesoma:containingthenucleusandotherpartsofthecellneededtosustainitslife.3.Axon:wirelikestructureendingintheterminalbuttonsthatextendsfromthecellbody.Myelinsheath:afattycoveringaroundtheaxonofsomeneuronsthatspeedsneuralimpulses.4.Terminalbuttons/endbuttons/terminalbranchesofaxon/synapticknobs:thebranchedendoftheaxonthatcontainsneurotransmitters.5.Neurotransmitters:chemicalscontainedinterminalbuttonsthatenableneuronstocommunicate.Neurotransmittersfitintoreceptorsitesonthedendritesofneuronslikeakeyfitsintoalock.6.Synapse:thespacebetweentheterminalbuttonsofoneneuronandthedendritesofthenextneuron.Classification:1.AfferentNeurons:takeinformationfromthesensestothebrain.2.Interneurons:Onceinformationreachesthebrainorspinalcord,interneuronstakethemessageandsendthemelsewhereinthebrainorontotheefferentneurons.3.EfferentNeurons(orMotorNeurons):takeinformationfromthebraintotherestofthebody.NeuronfiringNeuralfiringisanelectrochemicalprocess.Electricitytravelswithinthecell(fromthedendritestotheterminalbuttons)andchemicals(neurotransmitters)travelbetweencellsinthesynapse.Electricitydoesnotjumpbetweentheneurons.Restingstate:aneuronhasanoverallslightlynegativechargebecausethecellmembraneoftheneuronisselectivelypermeableandpreventstheseionsfrommixing.Firing:TheterminalbuttonsofneuronAarestimulatedandreleaseneurotransmittersintothesynapse—theseneurotransmittersfitintoreceptorsitesonthedendritesofneuronB.---enoughneurotransmittersarereceived(reachthethreshold),thecellmembraneofneuronBbecomespermeableandpositiveionsrushintothecell.(asshownbelowontherightpicture)Threshold:thelevelofquantityofneurotransmittersthatcanmakethecellmembranebecomepermeable.Actionpotential:theelectricmessagefiringwhenthechangeinchargespreadsdownthelengthofthenextneuron.(asshownbelowontheleftpicture)All-or-noneprinciple:aneuroneitherfirescompletelyoritdoesnotfire.cannotfirealittleoralot;theimpulseisthesameeverytime.Neurotransmitters1.Excitatoryneurotransmitters:neurotransmittersthatcanexcitethenextcellintofiring.2.Inhibitoryneurotransmitters:neurotransmittersthatcaninhibitthenextcellfromfiring.Eachsynapticgapatanytimemaycontainmanydifferentkindsofinhibitoryandexcitatoryneurotransmitters.Theamountandtypeofneurotransmittersreceivedonthereceptorsitesoftheneurondeterminewhetheritwillpassthethresholdandfire.(asshownbelow)NeurotransmittersimportanttoPsychologistsNeurotransmitterFunctionProblemsAssociatedwithanExcessorDeficitAcetylcholineMotormovementLackofacetylcholineisassociatedwithAlzheimer’sdisease(老年痴呆症)DopamineMotormovementandalertnessLackofdopamineisassociatedwithParkinson’sdisease(帕金森病),anoverabundanceisassociatedwithschizophrenia（精神分裂症）EndorphinsPaincontrolInvolvedinaddictions（成瘾）SerotoninMoodcontrolLackofserotoninisassociatedwithclinicaldepression（抑郁症）GABAImportantinhibitoryneurotransmitterSeizures（癫痫）,sleepproblemsGlutamateExcitatoryMigraines（偏头痛）,seizuresNorepinephrineAlertness,arousalDepressionOrganizationoftheNervousSystemCentralNervousSystemAllofthenerveshousedwithinbone(theskullandvertebrae)Brain+SpinalCordPeripheralNervousSystemAlltheothernervesinthebody(notencasedinbone)Autonomic+Somatic1.Autonomic:controlstheautomaticfunctionsofourbody(ourheart,lungs,internalorgans,glandsetc.).thefightorflightresponsetostress:sympathetic(mobilizeourbody)+parasympathetic(slowingdownourbodyafterastressresponse)Note:sympatheticnervoussystemacceleratessomefunctions(suchasheartrate,bloodpressureandrespiration)butconservesresourcesneededforaquickresponsebyslowingdownotherfunctions(suchasdigestion).2.Somatic:controlsourvoluntarymusclemovements(allowustomove)NormalPeripheralNervousSystemTransmissionstimulus—sensoryneurons—afferentnerves—brain—efferentnerves—musclesReflexes:animportantexceptionofabovestimulus—sensoryneurons—afferentnerves—spine—efferentnerves—musclesCertainreactionsoccurthemomentsensoryimpulsesreachthespinalcord.(ithasadaptivevalue,helpussurvive)eg:kneecapreflexes.Thissensoryinformationisprocessedbythespine,andthespinetellsyourkneetomove.Theinformationalsoreachesyourbrainbutonlyafterthisreflexeshasoccurred.TheBrainWaysofstudyingthebrain1.Accidentsdoctorstakenotesdocumentingthebraindamageandhowapatient’sbehaviorandpersonalitychangeaftertheaccident.2.Lesions(=destroy/remove)toremoveordestroypartofthebrain(notforexperimentalpurposesbutforsurgery).Afamoushistoricalexampleisthefrontallobotomy.Doctorslesionedpartofthefrontallobetomakethepatientscalmandrelievesomeserioussymtomsbutdrugtreatmentshavenowreplacedit.3.Electroencephalogram(EEG)(=brainwaves)detectsbrainwaves.Eg:insleepresearchtoidentifydifferentstagesofsleepinganddreaming4.ComputerizedAxialTomography(CATorCT)(=brain’sstructure)touseseveralsophisticatedX-raycamerasthatrotatearoundthebrainandcombineallthepicturesintoadetailedthree-dimensionalpictureofthebrain’sstructure(onlystructure,nofunctions).Ado