Perceptual Processes I: Visual and Auditory Recognition

1. Perceptual Processes I: Visual and Auditory Recognition Chapter 2

2. Cognition 7e, Margaret Matlin Chapter 2 Background on Visual Object Recognition The Visual System distal stimulus proximal stimulus retina sensory memory iconic memory, visual sensory memory occipital lobe primary visual cortex inferotemporal cortex

3. Cognition 7e, Margaret Matlin Chapter 2 Cerebral Cortex

4. Cognition 7e, Margaret Matlin Chapter 2 Background on Visual Object Recognition Organization in Visual Perception Gestalt Psychology figure ground ambiguous figure-ground relationship Explanation for figure-ground reversal adaptation of neurons in visual cortex people try to solve the visual paradox

5. Cognition 7e, Margaret Matlin Chapter 2 Figure-Ground Relationship

6. Cognition 7e, Margaret Matlin Chapter 2 Background on Visual Object Recognition Organization in Visual Perception Illusory Contours (subjective contours)

7. Cognition 7e, Margaret Matlin Chapter 2 Illusory Contours

8. Cognition 7e, Margaret Matlin Chapter 2 Background on Visual Object Recognition Theories of Visual Object Recognition Template-Matching Theory templates compare stimulus to templates until a match is found Problems inflexible only works for isolated letters, numbers, objects

9. Cognition 7e, Margaret Matlin Chapter 2 Background on Visual Object Recognition Theories of Visual Object Recognition Feature-Analysis Theory distinctive features Eleanor Gibson's research time to decide if two letters are different recognizing letters and numbers on envelopes

10. Cognition 7e, Margaret Matlin Chapter 2 Background on Visual Object Recognition Theories of Visual Object Recognition Feature-Analysis Theory Hubel and Wiesel's research single-cell recording technique orientation of a visual stimulus primary visual cortex feature detectors Problems with Feature-Analysis approach doesn't account for the relationship between features doesn't explain recognition of more complex objects

11. Cognition 7e, Margaret Matlin Chapter 2 Background on Visual Object Recognition Theories of Visual Object Recognition The Recognition-by-Components Theory Irving Biederman geons combining geons to form objects Problem standard viewpoint vs. different viewpoint Viewer-centered approach

12. Cognition 7e, Margaret Matlin Chapter 2 Geons

13. Cognition 7e, Margaret Matlin Chapter 2 Top-Down Processing and Visual Object Recognition The Distinction Between Bottom-Up Processing and Top-Down Processing bottom-up processing top-down processing Top-down processing is especially strong when stimuli are incomplete or ambiguous. Top-down processing is also strong when a stimulus is registered for just a fraction of a second. Combining bottom-up and top-down processing

14. Cognition 7e, Margaret Matlin Chapter 2 Top-Down Processing and Visual Object Recognition Top-Down Processing and Reading We don't read letter-by-letter Analyzing all the individual features in the letters of words would be too much work for the perceptual processes We can still manage to read a sentence, even if some of the middle letters in a word have been rearranged

15. Top down processing i cdnuolt blveiee taht I cluod aulaclty uesdnatnrd waht I was rdanieg. The phaonmneal pweor of the hmuan mnid, aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it dseno't mtaetr in waht oerdr the ltteres in a wrod are, the olny iproamtnt tihng is taht the frsit and lsat ltteer be in the rghit pclae. The rset can be a taotl mses and you can sitll raed it whotuit a pboerlm. Cognition 7e, Margaret Matlin Chapter 2

16. Cognition 7e, Margaret Matlin Chapter 2 Top-Down Processing and Visual Object Recognition Top-Down Processing and Reading Word superiority effect The context of a sentence facilitates the recognition of a word in a sentence Rueckl and Oden's �bears/beans� study both bottom-up and top-down processing operate in a coordinated fashion

17. Cognition 7e, Margaret Matlin Chapter 2 Rueckl & Oden�s �Bears/Beans� study

18. Cognition 7e, Margaret Matlin Chapter 2 Top-Down Processing and Visual Object Recognition In Depth: Overactive Top-Down Processing and Occasional Errors in Object Recognition Change Blindness fail to detect a change in an object or a scene Simons and Levin's stranger-and-the-door study Detecting the difference between two scenes identify important changes more quickly more likely to notice an improbable change do not store a detailed representation of a scene individual differences

19. Cognition 7e, Margaret Matlin Chapter 2 Top-Down Processing and Visual Object Recognition In Depth: Overactive Top-Down Processing and Occasional Errors in Object Recognition Inattentional Blindness fail to notice when an unexpected but completely visible object suddenly appears Simons and Chabris' basketball study awareness test YouTube - change blindness

20. Cognition 7e, Margaret Matlin Chapter 2 Top-Down Processing and Visual Object Recognition In Depth: Overactive Top-Down Processing and Occasional Errors in Object Recognition Similarities between change blindness and inattentional blindness both involve top-down processing when an object appears that is not consistent with their concepts, expectations, and memory, people often fail to recognize this changed object (change blindness) or this new object (inattentional blindness)

21. Cognition 7e, Margaret Matlin Chapter 2 Top-Down Processing and Visual Object Recognition In Depth: Overactive Top-Down Processing and Occasional Errors in Object Recognition ecological validity visual system is accurate in integrating the gist or general interpretation of a scene focus on what is important Theme 2: Our cognitive errors can often be traced to the use of a rational strategy

22. Cognition 7e, Margaret Matlin Chapter 2 Face Perception Should be a challenging task Recognizing faces from different angles, in different settings, with different expressions Recognizing Faces Versus Recognizing Other Objects Face perception as "special" Tanaka and Farah--facial features in context vs. isolation feature identification vs. holistic approach gestalt

23. Cognition 7e, Margaret Matlin Chapter 2 Face Perception Neuroscience Research on Face Recognition brain lesion research prosopagnosia inferotemporal cortex single-cell recording technique in monkeys fMRI studies brain's response to faces in upright and upside-down positions

24. Cognition 7e, Margaret Matlin Chapter 2 Face Perception Applied Research on Face Recognition cashiers' judgments about ID photos (Kemp and colleagues 1997) security surveillance systems (Burton and colleagues 1999) familiarity and expertise

25. Cognition 7e, Margaret Matlin Chapter 2 Face Perception Individual Differences: Face Identification in People with Schizophrenia schizophrenia use of top-down processing in visual perception difficulty perceiving faces same/different person same/different emotion

26. Cognition 7e, Margaret Matlin Chapter 2 Speech Perception Record sound vibrations of someone talking Translate vibrations into a sequence of sounds that you perceive to be speech Distinguish the sound pattern of one word from all other irrelevant words Separate voice of speaker from background noise, including other conversations

27. Cognition 7e, Margaret Matlin Chapter 2 Speech Perception Characteristics of Speech Perception Word Boundaries Listeners can impose boundaries between words, even when these words are not separated by silence. Variability in Phoneme Pronunciation Phoneme pronunciation varies tremendously pitch, tone, and rate lack of precision, sloppy pronunciation coarticulation

28. Cognition 7e, Margaret Matlin Chapter 2 Speech Perception Characteristics of Speech Perception Context and Speech Perception Context allows listeners to fill in missing sounds. Phonemic restoration Warren & Warren's wheel/heel/peel study Fail to notice mispronunciations Role of top-down processing

29. Cognition 7e, Margaret Matlin Chapter 2 Speech Perception Characteristics of Speech Perception Visual Cues as an Aid to Speech Perception Visual cues from the speaker�s mouth help us interpret ambiguous sounds. McGurk effect YouTube - The McGurk effect

30. Cognition 7e, Margaret Matlin Chapter 2 Speech Perception Theories of Speech Perception The Special Mechanism Approach speech-is-special approach humans are born with a specialized device that allows us to decode speech stimuli (phonetic module or speech module) we process speech sounds more quickly and accurately than other auditory stimuli categorical perception

31. Cognition 7e, Margaret Matlin Chapter 2 Speech Perception Theories of Speech Perception The General Mechanism Approaches humans use the same neural mechanisms to process both speech sounds and nonspeech sounds speech as learned ability event-related potential studies phoneme judgment and visual cues