Slides

PsychExchange.co.uk Shared Resource

Description
1. Perceptual Organisation How do we make sense of the world around us? 2. The information-processing approach... <ul><li>How can a human mind be compared to…
Categories
Published
of 43
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Related Documents
Share
Transcript
  • 1. Perceptual Organisation How do we make sense of the world around us?
  • 2. The information-processing approach... <ul><li>How can a human mind be compared to a computer? </li></ul><ul><li>How can we represent the flow of information through our cognitive systems? </li></ul><ul><li>What do we mean by bottom-up and top-down processing? </li></ul>
  • 3. Bottom-up and Top-down processing
  • 5. Top down processing <ul><li>You dnot need all the ltetres of wrdos to be in the croerct odrer to raed a snetncee. </li></ul>
  • 6. Top down and bottom-up processing <ul><li>Write a clear definition of bottom up and top down processing. </li></ul><ul><li>Use p. 228 and some examples to explain in your own words. </li></ul>
  • 7. Theories of perception <ul><li>You need to be able to describe and evaluate the two contrasting approaches or theories of perception: </li></ul><ul><li>The Direct Theory of perception (Gibson) and </li></ul><ul><li>The Constructivist theory of perception (Gregory). </li></ul>
  • 8. Direct theories of perception <ul><li>Important to study perception in real world environments. </li></ul><ul><li>Ecological approach </li></ul><ul><li>Gibson (1979) </li></ul><ul><li>Helped develop training programmes for pilots during WW II. </li></ul><ul><li>Basic idea: the information taken in by our sensory receptors is all that we need to perceive the world and there is not need to involve past experience. </li></ul>
  • 9. Evaluating theories of perception <ul><li>Gibson – direct theory of perception </li></ul><ul><li>+ Emphasises the importance of movement of the observer. </li></ul><ul><li>+ Practical applications – pilots and traffic control techniques. </li></ul><ul><li>+ Biological support </li></ul><ul><li>The idea of affordances can be criticised </li></ul><ul><li>Does not explain visual illusions </li></ul>
  • 10. Evaluating theories of perception <ul><li>Gregory – Constructivist Approach </li></ul><ul><li>+ It makes sense that we use top down information, particularly in ambiguous situations. </li></ul><ul><li>+ This theory accounts for why we perceive visual illusions. </li></ul><ul><li>There tends to be an over-emphasis on errors.... </li></ul><ul><li>How do visual illusions persist even if we know that we are being ‘tricked’? </li></ul>
  • 11. Explanations of perceptual organisation <ul><li>In order to make sense of the material coming in via our senses we need to organise it. </li></ul>
  • 12. How do we perceive distance? <ul><li>The image that falls on our retina is 2-dimensional. </li></ul><ul><li>The distance of an object (or its depth in the visual field) is 3-dimensional </li></ul><ul><li>SO, how do we perceive DEPTH? </li></ul>
  • 13. How do we perceive depth? <ul><li>Use BINOCULAR depth cues – information from BOTH eyes. </li></ul><ul><li>Pencil demonstration! </li></ul><ul><li>Retinal disparity </li></ul><ul><li>Ocular convergence </li></ul>
  • 14. Why two eyes are better <ul><li>Hold two pencils at arm ’ s length away from your body. Close one eye. Try to bring the pencils together so that the points touch each other. </li></ul><ul><li>Repeat this with the other eye closed and then with both eyes open. </li></ul><ul><li>Is it easier to do this with one eye open or with both eyes open? Why? </li></ul>
  • 15. How do we perceive depth? <ul><li>(2) Monocular depth cues </li></ul><ul><li>How can we perceive depth </li></ul><ul><li>With only ONE eye? </li></ul>
  • 16. Monocular depth cues
  • 17. Monocular Depth cues
  • 18. Monocular Depth cues
  • 19. Monocular Depth Cues
  • 20. Size constancy… <ul><li>The ability to perceive size as unchanging despite changes in the size of the image on the retina. </li></ul><ul><li>Get in to pairs. One of you take </li></ul><ul><li>a Constructivist approach and </li></ul><ul><li>the other a direct theory </li></ul><ul><li>Approach. </li></ul><ul><li>Can you both explain size constancy? </li></ul>
  • 22. Size Constancy Constructivist Direct
  • 23. Shape constancy What is shape constancy?
  • 24. Shape constancy <ul><li>Swap around in your pair. </li></ul><ul><li>Explain shape constancy using ideas from a Constructivist or Direct perspective. </li></ul><ul><li>What evidence is there against the direct theory of shape constancy? </li></ul>
  • 25. Visual Illusions <ul><li>We normally have a stable view of the world. </li></ul><ul><li>We engage in ‘Veridical perception’ when our perception matches the physical world. This can only occur when viewing conditions are good. </li></ul><ul><li>In certain situations we may make errors.... </li></ul><ul><li>Examples?? </li></ul>
  • 26. Visual Illusions <ul><li>Visual illusions are artificially created to test mis-perception. </li></ul><ul><li>Gregory identified FOUR categories of visual illusion. </li></ul><ul><li>Ambiguous figures </li></ul><ul><li>Paradoxical figures </li></ul><ul><li>Fictitious figures </li></ul><ul><li>distortions </li></ul>
  • 27. Visual Illusions
  • 28. Visual Illusions
  • 29. Visual Illusions Young or old?
  • 30. The Muller-Lyer illusion <ul><li>Gregory – we impose our knowledge of a 3-D world onto a 2-D image. </li></ul><ul><li>Day – ‘conflicting cues theory’  we have to make sense of 2 cues when judging the length of the lines – the actual length of the line and the overall length of the figure. </li></ul>
  • 31. Past Exam Questions <ul><li>Describe and evaluate one constructivist theory of visual perception (24) </li></ul><ul><li>a) Describe one direct theory of perception (12) </li></ul><ul><li>b) Evaluate this theory (12) </li></ul><ul><li>3. Discuss explanations of perceptual organisation (e.g. depth, movement, illusions and constancies </li></ul>
  • 32. The Nature versus Nurture debate <ul><li>Nativists </li></ul><ul><li>Empiricists </li></ul><ul><li>How can we investigate if perceptual abilities are innate or learned? </li></ul>
  • 33. Infant (neonate) Studies Why are babies the best participants to use for this research?
  • 34. What are the difficulties of research using neonates as participants? <ul><li>Ethics </li></ul><ul><li>Difficult to attract their attention </li></ul><ul><li>? </li></ul><ul><li>? </li></ul><ul><li>? </li></ul>
  • 35. How can we overcome these difficulties? Techniques used in neonate research Preferential looking habituation Sucking rate Heart and breathing rate PET scans
  • 36. Testing acuity and contrast <ul><li>Visual acuity – define it. </li></ul><ul><li>Acuity is poor in newborns – must be at distance of 20 feet in order to perceive at the same level of acuity as an adult at 800 feet. </li></ul><ul><li>Why do babies have such poor acuity? </li></ul><ul><li>Babies also have poor colour contrast due to an under-developed fovea. </li></ul>
  • 37. Face recognition <ul><li>If we wanted to test if face recognition is innate what could we do? </li></ul><ul><li>Remember the problems with baby research! </li></ul>
  • 38. Fantz (1961) Fantz (1961) used the preference method to study face perception. He showed infants (aged between 4 days and 5 months) pairs of face-shaped discs and measured the amount of time spent fixating each one. There were realistic faces, scrambled faces, and blank faces. Infants of all ages looked most at the realistic face and least at the blank face, suggesting the ability to recognise faces is either innate or learned shortly after birth. Clearer evidence as to whether face recognition is innate requires <ul><li>Why did Fantz use a blank face? </li></ul>Be able to describe and evaluate a study into infant perceptual development
  • 39. Evaluating research into face recognition.... <ul><li>Think about.... </li></ul><ul><li>What does the research tell us? </li></ul><ul><li>Can we criticise Fantz’s study? Why? </li></ul><ul><li>Is there any other support for Fantz? </li></ul>
  • 40. Depth and Distance Perception <ul><li>How could we test depth perception in infants? </li></ul>
  • 41. Visual Constancies <ul><li>Why are constancies important? </li></ul><ul><li>Size constancy – Bower (1965) </li></ul><ul><li>Read the study and answer the questions which follow. </li></ul><ul><li>What conclusions can we draw from Bower’s research? </li></ul>
  • 42. Shape constancy <ul><li>Bower (1966) – 2 month old infants respond to a tilted rectangle as if it were a normal rectangle. </li></ul><ul><li>Kaye and Bower (1994) – babies can link the shape of a dummy inside the mouth with the actual shape seen on a screen. </li></ul><ul><li>- What do these pieces of research tell us about shape perception? </li></ul><ul><li>- Can you criticise the research in any way? </li></ul>
  • 43. Infant studies: Summary <ul><li>In order to make a valid conclusion to any essay on infant perception research, you need to be able to analyse the nature versus nurture debate, and look at which bits of evidence support each side of the argument. </li></ul>Nature Nurture
  • We Need Your Support
    Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

    Thanks to everyone for your continued support.

    No, Thanks