认知心理学课件：2知觉

1、12What is perception for?nRegistering the information that arrives at our eyes and earsnPlacing some sort of interpretation on that informationThe perception is much more than simply the registering of sensory information3How do our sensory systems identify what is in the outside worldnIt combines a

2、spects of both the outside world (the visual or auditory stimuli) and our own inner world (our previous knowledge). That is, it combines both bottom-up and top-down processing知识刺激知觉系统Top-down processingbottom-up processing4nPerception in different modalitiesnvision, audition (speech, non-speech), ol

3、faction (smell), gustation (taste), touch5Sensation, Perception, & CognitionnWhere to draw the line between perception and cognition, or even between sensation and perception?nIt is better to view these processes as part of a continuum, in which information flows through the system, with differe

4、nt processes designed to address different questionsnQuestions of sensation focus on qualities of stimulationnQuestions of perception are focus more on identity, form, pattern, and movementnCognition occurs as perceptual information is used to serve further goalSometimes we cannot perceive what does

5、 existSometimes we perceive things that does not exist8At other times, we perceive what cannot be there11视觉模式识别（Visual Pattern Recognition）nPatternn视觉刺激在空间中的复杂排列方式nThe task of pattern recognition is to identify what these objects in the visual world are12模板匹配模型（Template-Matching Models）nA retinal im

6、age of an object is faithfully transmitted to the brain and an attempt is made to compare it directly to various stored patternsnThese patterns are called templatesnThe perceptual system tries to compare the letter to the templates it has for each letter and reports the template that gives the best

7、matchTemplate-Matching Models14Template-Matching ModelsnThings can go wrong very easily with a template. A mismatch occurs when the imagenfalls on the wrong part of the retinanis a wrong sizenis in a wrong orientationnis nonstandard lettersnThe fact that a very standardized character system is neede

8、d for template matching to work reduces the credibility of this process as a model for human pattern recognitionnIn humans, pattern recognition is very flexible15原型模型（Prototype Models）nA prototype is the best-guess (abstract, idealized) example of a class of related objects or patterns, which integr

9、ates all of the most typical (most frequently observed) features of the form or patternnhighly representative of a patternndoes not need precise, identical match; minor variations are allowednWe seem to be able to form prototypes even when have never seen an exemplar that exactly matches the prototy

10、pe16区别性特征模型（Distinctive-Features Models）nWe match features of a pattern to features stored in memory, rather than to match a whole pattern to a template or a prototypenStimuli are thought of as combinations of elemental features (e.g., horizontal, vertical, or diagonal lines, and curves)nPattern rec

11、ognition occurs through feature analysis17Feature model has a number of advantages over the template modelnSince the features are simpler, it is easier to see how the system might try to correct for the kinds of difficulties caused by template modelsnIt is possible to specify those relationship amon

12、g the features that are most critical to the patternnUse of features rather than larger patterns will reduce the number of templates needed; same features tend to occur in many patterns18nImage demonsnretinal imagesnFeature demonsnmatching retinal images to featuresnCognitive demonsnfeature combinat

13、ionsnDecision demons19Navon, D. (1977). Forest before trees: The precedence of global features in visual perception. , 353-38321Global Precedence Effect(Navon, 1977)nGlobal featuresnthe features that give a form its overall shapenLocal featuresnconstitute the small scale or detailed aspects of a giv

14、en form22Kinney, G.C., Marsetta, M., Showman, D.J., 1966. Studies in display symbol legibility, part XII. The legibility of alphanumeric symbols for digitized television. The Mitre Corporation, Bedford, MAnLetters are presented for very brief intervalsnFor the letter G, 29 errors were made by subjec

15、ts. Of these errors,n21 involved misclassification as Cn6 misclassifications as On1 misclassification as Bn1 misclassification as 923R.W.斯佩里 D.H.休伯尔T.N.威塞尔24Physiological and Neurological Evidence for Feature TheoriesnHubel, 1982; Hubel & Wiesel, 1965, 1979nHubel, D. H. 1982. Exploration of the

16、primary visual cortex, 1955-78. Nobel lecture. Nature, 299, 515-524.nfeature detectors (特征觉察器), receptive field (感受野)February 27, 1926 - September 22, 2013nThese cells seem to show a hierarchical structure in the degree of complexity of the stimuli to which they respondnthe size of the receptive fie

17、ld increases, as does the complexity of the stimulus required to prompt a response2526Gibson, J. J. (1969). The Senses Considered as Perceptual Systems. Boston: Houghton-Mifflin.Same or different?P RG M27What and Where PathwaysnSeparate neural pathways in the cerebral cortex for processing different

18、 aspects of the same stimulinThe “what” pathway descends from the primary visual cortex in the occipital lobe towards the temporal lobes, and is mainly responsible for processing the color, shape, and identity of visual stimulinThe “where” pathway ascends from the occipital lobe towards the parietal

19、 lobe, and is responsible for processing location, and motion informationV1 LGN29n成分识别理论（Recognition-by-components theory, Biederman, 1987, 1990）nWe form stable three-dimensional mental representations of objects by manipulating a few simple geometric shapes, i.e., a set of three-dimensional geons (

20、for geometrical ions)nAccordingly, we quickly recognize objects by observing the edges of objects and then decomposing them into geons, which also can be recomposed into alternative arrangementsBiederman et al., 1985 (also see Biederman, 1987)Biederman, I., Beiring, E., Ju, G., & Buckle, T. (198

21、5). A comparison of the perception of partial vs. degraded objects. Unpublished manuscript, State University of New York at Bufialo.Biederman, I. (1987). Recognition-by-Components: A Theory of Human Image Understanding. Psychological Review, 94, 115-147 Irving Biederman: /biederman

22、/知识刺激知觉系统Top-down processingbottom-up processing34nBottom-up processing-driven or data-driven processingnTop-down processing driven processingnknowledge, expectations353637Schacter, D.L., Cooper, L.A., Delaney, S.M., Peterson, M.A., & Tharan, M. (1991). Implicit memory for possible and impossibl

23、e objects: Constraints on the construction of structural descriptions. Journal of Experimental Psychology: Learning, Memory, & Cognition, 17, 3-19.38nMany cognitive processes rely on both bottom-up and top-down processing39Investigating Perception:40The Ponzo IllusionnIt occurs because of the de

24、pth cue provided by the converging lines41Muller-Lyer IllusionnReasons not fully understood; the diagonal lines may be implicit depth cues similar to the ones we see in our perception of the exterior and interior of a building42Relative Size IllusionnThe size of the center circle relative to the sur

25、rounding circles affect perception of the center circles sizeFraser IllusionTilt Illusion47Repulsion Effect in Tilt Illusion48Several Parameters Influencing the Magnitude of the Tilt Illusion (Smith & Wenderoth, 1999, Vision Research, 39, 4113-4121)nAnglesnRepulsion effect: 60, 15nAttraction eff

26、ect: 6090, 75nTest stimuli durationnRepulsion effectnAttraction effectnContrast49Multistable Perception in the Monkey BrainLeopold, D.A., & Logothetis, N.K. (1999). Multistable phenomena: Changing views in perception. Trends in Cognitive Science, 3, 254-264.53Palmer, S. E. (1977) Hierarchical st

27、ructure in perceptual representation. Cognitive Psychology, 9, 441-474.Who can understand this sentence?FoRiNsTaNcEtHiSsEnTeNcEiShArDtOrEaDn知觉组织线索的相对强度 (如规则性和邻近性，van Lier & Wagemans, 1997)57nFox, E. (1998). Perceptual grouping and visual selective attention. Perception & Psychophysics, 60, 1

28、004-1021nFuentes, L. J., Humphreys, G. W., & Agis, I. F., et al. (1998). Object-based perceptual grouping affects negative priming. Journal of Experimental Psychology: Human Perception and Performance, 24, 664-67258Faces: The fascinating test case for many of the central questions in cognitive n

29、eurosciencenTo what extent does visual cognition rely on domain-specific processing mechanisms? (Domain Generality vs. Domain Specificity- Key Themes)nHow do these specialized cognitive mechanisms arise?nHow autonomous are they, and how do they interact with other cognitive system? (Interactive vs.

30、Modular)59Questions on Face ProcessingnHow are faces perceived?nHow does their processing differ from that of nonface stimuli?nAre the systems for face perception and object perception functionally independent? Can each operate without the other?nDo the two systems process information differently?nD

31、o the processes in face and object perception involve physically distinct mechanisms? Do face and object perception depend on different regions of the brain?nHow does the interaction of evolutionary and experiential forces have produced a neural mechanism that still outperforms the best computer vis

32、ion algorithms?60Margaret Thatcher IllusionThompson, 1980Thompson, P. (1980). Margaret Thatcher: A new illusion. Perception, 9(4), 483-48461Rotate this!62Rotate this!63Inversion effects in Face Processingndue to a disruption of that is specific to faces, or stimuli that have a comparable level of ex

33、pertiseninverted faces are processed by features and upright faces by (including subtle differences in the relative placement of the eyes and mouth)67nInversion effectna marker of face-specific processes and a tool for investigating what makes face-recognition special68Nonhuman primate species also

34、exhibits the Thatcher effectnAdachi, I. et al. (August 11, 2009). Thatcher effect in monkeys demonstrates conservation of face perception across primates. , 1270-1273nFour 4-year-old male rhesus monkeys (恒河猴)nSuch a study is important fornthe study of cognitive evolution (continuity between humans a

35、nd nonhumans in the mechanisms of face perception)nthe appropriate use of primate models in social cognition researchAdachi, I. et al. (August 11, 2009). Thatcher effect in monkeys demonstrates conservation of face perception across primates. , 1270-1273Adachi, I. et al. (August 11, 2009). Thatcher

36、effect in monkeys demonstrates conservation of face perception across primates. , 1270-1273the original(intact) and the thatcherized versions of the habituated facewere presented in the same orientation used in the habituationphase71Within-items design舒华, 张亚旭. (2008). 心理学研究方法：实验设计和数据分析. 北京：人民教育出版社74

37、Bottom linenMonkeys perceive faces configurallynThis configural processing is disrupted when the face is invertednThe mechanism for distinguishing among many similar faces may have evolved in an ancestor common to humans and rhesus monkeys 30 million or more years ago75nThe configural setnThe featur

38、al set76nThe deprivation of patterned visual input from birth until 2-6 months of age results in permanent deficits in configural face processing (Le Grand et al., 2001, Nature, 410, 890, for correction, see 412, 786)n14 patients born with a dense central cataract in each eye that prevented patterne

39、d stimulation from reaching the retinanafter removal of the natural lens, an optical correction was fitted to focus visual input (mean duration of deprivation, 118 days from birth; range, 62-187 days)nthey had had at least nine years of visual experience after treatment before testingnseverely impai

40、red at differentiating faces that differed only in the spacing of their featuresnnormal in distinguishing those varying only in the shape of individual featuresnThese findings indicate that early visual input is necessary for normal development of the neural architecture that will later specialized

41、for configural processing of faces78ERP Effects for the Thatcher IllusionnCarbon, C. C., Schweinberger, S. R., Kaufmann, J. M., & Leder, H. (2005). The Thatcher Illusion seen by the brain: An event-related brain potentials study. 544-5558084Bottom linenA clear difference in N170 between inverted

42、 Thatcherized and inverted Original facesnInverted Thatcherized faces are processed differently compared to normal faces, although they perceptually look quite like normal faces85Eyes first! Eye processing develops before face processing in children (Taylor et al., 2001, NeuroReport)nParticipantsn90

43、 children, 15 for each group (4-5 to 14-15 years)n38 adultsnCritical Stimulinupright facesninverted facesnEyesnphase-scrambled facesnpictures of flowers86nA checkerboard (probability 0.12) was the target stimulusnsubjects made a button press to targets88899091nUpright faces showed the slowest change

44、s with agenThis suggests that is a more complex processing strategy and requires longer to develop to the adult level of expertise92Farah et al., 1994nWithin-category discrimination for faces and eyeglassesnRecognition memorynPatient LHnface 64%, eyeglasses 69%ncontrol: face 85%, eyeglasses 69%nAnot

45、her patientnface 98%, eyeglasses 50%93Tanaka & Farah, 1993nStudy phasenassociate names with faces or housesnTest phasenforced choice (part vs. whole condition)nResultsnno difference between the whole and part conditions for housesnperformance in the whole condition was much better than in the pa

46、rt condition for facesnConclusionnObject recognition is analytic and part-based, whereas face recognition is holistic and configuralnIdentity (actor/non-actor) vs. gender discrimination 12nViewing faces vs. non-sense pictures 33, 32nViewing faces vs. non-face objects 6, 79596The Models of Face Recog

47、nitionnCognitive Model (Bruce & young, 1986)nNeural Model (Haxby et al., 2000)9899100102103de Gelder & Rouw, 2000n面孔失认（prosopagnosia）病人LHn46岁，男性。交通事故和后来的手术损伤了大脑双侧颞枕交界处、右侧额叶以及颞前区n临摹、绘画、阅读和书写基本正常，说明真实物体和图片的识别轻微受损n然而，深度面孔失认n不能认出朋友或邻居的面孔，甚至不认识自己妻子和孩子的面孔104de Gelder & Rouw, 2000105de Gelder &

48、amp; Rouw, 2000107Self Face RecognitionnKeenan et al. 2001. Nature, 409, 305n5 right-handed patients with epilepsynWada tests (和田试验和田试验)nremember the picture presented and choose the picture of the face that they had been shown109Keenan et al. 2000. Neuropsychologia, 38, 1047-1053nMaterialsnself-fam

49、ous vs. familiar-famousnTasknface identification task (stop the movie when the face in the sequence became famous)nleft vs. right handnInterestnhand response differences112Resultsnself-left:53.3 %nself-right:43.3 %nfamiliar-left:44.4 %nfamiliar-right:41.7 %114nWhat are the fundamental approaches to

50、explaining perception?nHow does face perception differ from object perception?nWhat are the two basic models of face recognition?115Reading List (1)nChurchland & Churchland. Neural worlds and real worlds. Nature Reviews Neuroscience, 2002, 11, 3, 903-907nShimojo, Paradiso, and Fujita. What visua

51、l perception tells us about mind and brain. PNAS, 2001, 98, 12340-12341nMoutoussis & Zeki. The relationship between cortical activation and perception investigated with invisible stimuli. PNAS, 2002, 99, 9527-9532116Reading List (2)nGepshtein and Kubovy. The emergence of visual objects in space-time. PNAS, 2000, 97, 8186-8191nIs perception discrete or continuous? Trends in Cognitive Sciences, 2003, 7, 207-213nKeeping perception accurate. Trends