AP-psychology总结Unit4

1Chapter4SensationandPerceptionSensation&perceptionSensation:anactivationofoursenses.Perception:theprocessofunderstandingthesesensations.Transductionaprocessthroughwhichsignalsaretransformedintoneuralimpulses.Signals—neuroimpulses—thalamus—differentcorticesofthebrain(thesenseofsmellistheoneexceptiontothisrule.)SensoryadaptationdecreasingresponsivenesstostimuliduetoconstantstimulationSensoryhabituation/Perceptualadaptationourperceptionofsensationsispartiallyduetohowfocusedweareonthem.Cocktail-partyphenomenonWhiletalkingtoafriend,yourattentionwillinvoluntarilyswitchacrosstheroomwhensomeonesaysyourname.EnergysensesVision（electromagneticwaves）,hearing(vibrationinair)andtouch.Theygatherenergyinformoflight,soundwaves,andpressure.Chemicalsensestasteandsmell.BodypositionsensesVestibularandkinesthetichelpwithbodypositionandbalance.VisionGeneralprocess:Step1:GatheringlightStep2:WithintheeyeStep3:TransductionStep4:InthebrainStep1:Gatheringlight1.Thecolorweperceiveddependsonintensity强度andlightwavelength光波长.a)Intensitydescribeshowmuchenergythelightcontains,howbrighttheobjectappears.b)Lightwavelengthdeterminestheparticularhuewesee.c)Lightwavelength:Ultraviolentwaves紫外线/X-raysvisiblelightinfraredwaves红外线/microwaves/radiowaves2.a)Aredshirtreflectsredlightandabsorbsothercolors.2b)Ablackshirtabsorbsallcolors.c)Awhiteshirtreflectsallcolors.Step2:WithintheeyeProcess:Light—cornea—pupil—lens—retinaa)Cornea角膜:aprotectivecovering.b)Pupil瞳孔:liketheshutterofacamera.Iris虹膜arethemusclesthatcontrolthepupil.c)Lens晶状体:onwhichlightfocusesthroughaprocesscalledaccommodation.Itiscurvedandflexibleinordertofocusthelight.d)Retina视网膜:theimageisprojectedonitupsidedown.Likeascreen.Onthisscreenarespecializedneuronsthatareactivatedbythedifferentwavelengthsoflight.Step3:Transduction1、Transduction:thetranslationofincomingstimuliintoneuralsignals.Transductionoccurswhenlightactivatestheneuronsintheretina.2、Retina视网膜1)Thefirstlayerofcells:cones(cellsthatareactivatedbycolor),androds(cellsthatrespondtoblackandwhite)a)Rodsoutnumbercones(theratioisapproximately20:1).b)Rodsaredistributedthroughouttheretinawhileconesareconcentratedtowardthecenteroftheretina.c)Fovea:attheverycenteroftheretina,anindentationthatcontainsthehighestconcentrationofcones.d)Peripheralvision:relyingonrodsandmostlyinblackandwhite.2)Ifenoughrodsandconesfireinanareaoftheretina,theyactivatethenextlayerofbipolarcells.3)Ifenoughbipolarcellsfireinanareaoftheretina,theyactivatethenextlayerofcells:ganglioncellsGanglioncells—sendsimpulsestoLGN(lateralgeniculatenucleus,aspecificregioninthethalamus)—sendtovisualcortices(locatedintheoccipitallobesofthebrain)3、Blindspot:thespotwheretheopticnerveleavestheretinahasnorodsorcones4、Opticchiasm:thespotwherethenervescrosseachother:impulsesfromtheleftsideoreachretinagotothelefthemisphere.Viceversa.3Step4:InthebrainDebate:stilldonotknowwherethemessageistranslatedintoperceptionMessagesendtothevisualcortex—thenactivatefeaturedetectors:todetectdifferenttypesofvisualimagessuchasverticallines,curves,motion,andmanyotherfeaturesofimages.Whatweperceivevisuallyisacombinationofthesefeatures.TheoriesofColorVision1.Trichromatictheory(ortheYoung-HelmholtzTrichromatictheory):1)wehavethreetypesofconesintheretinathatdetectthedifferentcolorsblue,red,andgreen(theprimarycolorsoflight).2)Defect:itcannotexplainthefollowingtheories:a)Colorblindness:Individualswithdichromaticcolorblindnesscannotseeeitherred/greenshadesorblue/yellowshades.Themonochromaticcolorblindnesscausespeopletoseeonlyshadesofgray.b)Afterimages:ifyoustareatonecolorforawhileandthenlookatawhiteorblankspace,youwillseeacolorafterimage.2.Opponent-processtheory:1)thesensoryreceptorsarrangedintheretinacomeinpairs:red/greenpairs,yellow/bluepairs,andblack/whitepairs.2)Ifonesensorisstimulated,itspairininhibitedfromfiring.3)Thistheoryprovidesagoodexplanationforcolorafterimagesandcolorblindness.Mostresearchersagreewithacombinationofthesetwotheories.Theimportantthingtorememberisthatboththeoriesareneededtoexplaincolorvisionfully.Hearing1.Soundwaves:1)Amplitude:theheightofthewaveanddeterminestheloudnessofthesound,whichismeasuredindecibels.42)Frequency:thelengthofthewavesanddeterminespitch,measuredinmegahertz.3)High-pitchedsoundshavehighfrequencies,andthewavesaredenselypackedtogether.Low-pitchedsoundshavelowfrequencies,andthewavesarespacedapart.Thetallerthewaves,themoreenergyandthelouderthenoise.2.Generalprocess:Outerear/pinnaearcanaleardrum/tympanicmembraneossicles(hammer/malleusanvil/incusstirrup/stapes)ovalwindowcochlea耳蜗basilarmembranehaircellsorganofCortiauditorynervebrainPinna:tocollectsoundwaves.Ear/auditorycanal:throughwhichthewavestravel.Eardrum:athinmembranethatvibrateswhensoundwaveshitit.Theossicles:thefirstofwhichisattachedtoeardrum.Hammer/malleusisconnectedtoanvil/incus,whichthenconnectstothestirrup/stapes.Ovalwindow:amembraneverysimilartotheeardrum.Cochlea:astructureshapedlikeasnail’sshellfilledwithfluid.Astheovalwindowvibrates,thefluidmoves.Basilarmembrane:thefloorofthecochlea.OrganofCorti:neuronsactivated