1 / 55

Orienting Attention

Orienting Attention. Posner Cue - Target Paradigm:. Subject presses a button as soon as x appears. Orienting Attention. Posner Cue - Target Paradigm:. Orienting Attention. Posner Cue - Target Paradigm:. Orienting Attention. Posner Cue - Target Paradigm:. Orienting Attention.

kiral
Download Presentation

Orienting Attention

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Orienting Attention • Posner Cue - Target Paradigm: Subject presses a button as soon as x appears

  2. Orienting Attention • Posner Cue - Target Paradigm:

  3. Orienting Attention • Posner Cue - Target Paradigm:

  4. Orienting Attention • Posner Cue - Target Paradigm:

  5. Orienting Attention • Posner Cue - Target Paradigm: X

  6. Orienting Attention • Posner Cue - Target Paradigm:

  7. Orienting Attention • Posner Cue - Target Paradigm: That was a validly cued trial because the x appeared in the box that flashed

  8. Orienting Attention • Posner Cue - Target Paradigm:

  9. Orienting Attention • Posner Cue - Target Paradigm:

  10. Orienting Attention • Posner Cue - Target Paradigm:

  11. Orienting Attention • Posner Cue - Target Paradigm: X

  12. Orienting Attention • Posner Cue - Target Paradigm:

  13. Orienting Attention • Posner Cue - Target Paradigm: That was an invalidly cued trial because the x appeared in the box that didn’t flash

  14. Paradigms Used To Study Attention • Posner Cue - Target Paradigm: Attention Effect = Valid RT - Invalid RT

  15. Voluntary Orienting • Under what circumstances would a cue lead to a voluntary shift of attention?

  16. Voluntary Orienting • Under what circumstances would a cue lead to a voluntary shift of attention? • Informative cue • Validity = greater than 50%

  17. Voluntary Orienting • Under what circumstances would a cue lead to a voluntary shift of attention? • Informative cue • Validity = greater than 50% • What is another way to make this paradigm a voluntary orienting paradigm?

  18. Voluntary Orienting • What is another way to make this paradigm a voluntary orienting paradigm? Symbolic Cue Symbolic cues may orient attention towards another location. Stimulus cues orient attention to the stimulated location.

  19. Voluntary Orienting • What is the time course of voluntary orienting? Invalidly Cued Targets Response Time Validly Cued Targets Cue - Target Interval About 200 ms

  20. Reflexive Orienting • Attention can be automatically “summoned” to a location at which an important event has occurred:

  21. Reflexive Orienting • Attention can be automatically “summoned” to a location at which an important event has occurred: • Loud noise • Motion • New Object • We call this attentional capture Transients

  22. Reflexive Orienting • The Posner cueing paradigm (with blinking boxes) confounds reflexive and voluntary orienting … in what way?

  23. Reflexive Orienting • The Posner cueing paradigm (with blinking boxes) confounds reflexive and voluntary orienting • How could we change the Posner cueing paradigm to make it asses only reflexive orienting?

  24. Reflexive Orienting • The Posner cueing paradigm (with blinking boxes) confounds reflexive and voluntary orienting • How could we change the Posner cueing paradigm to make it asses only reflexive orienting? • Make validity 50% (non-informative cue)

  25. Reflexive Orienting • Time course of reflexive orienting is counterintuitive Response Time Valid Invalid 0 500 1000 About 50 ms Cue - Target Interval (ms)

  26. Reflexive Orienting • Time course of reflexive orienting is counterintuitive • Delayed response at validly cued location after long cue-target interval is known as inhibition of return (IOR)

  27. Reflexive Orienting • Time course of reflexive orienting is counterintuitive • Delayed response at validly cued location after long cue-target interval is known as inhibition of return (IOR) • Thought to occur because attention goes to cued location, then leaves and is inhibited from returning

  28. Reflexive Orienting • Can symbolic cues be reflexive? Almost never but …

  29. Reflexive Orienting • Can symbolic cues be reflexive? Reflexive orienting to direction of eye gaze

  30. Reflexive Orienting • Potential cues for Reflexive Orienting • Loud noise • Motion • New Object • New Objects are powerful attention grabbers! Transients

  31. New Objects Capture Attention IS THERE AN “H”? Initial scene viewed for several hundred ms Yantis & Jonides (1990): New-Object Paradigm

  32. New Objects Capture Attention IS THERE AN “H”? New scene: search for target letter H may be revealed from and 8 or may appear as a new object Yantis & Jonides (1990): New-Object Paradigm

  33. Reflexive Orienting • Steven Yantis and colleagues • Result:

  34. Reflexive Orienting • Steven Yantis and colleagues • Result: Targets are found faster when they are “new objects” than when they are revealed from “old” objects

  35. Reflexive Orienting • Steven Yantis and colleagues • Interpretation: The visual system prioritizes in dealing with visual objects - relatively recent objects are “flagged” while older objects are disregarded

  36. The Physiology of Attention

  37. Physiology of Attention • Neural systems involved in orienting • Neural correlates of selection

  38. Disorders of Orienting • Lesions to parietal cortex can produce some strange behavioural consequences Parietal Lobe

  39. Disorders of Orienting • Lesions to parietal cortex can produce some strange behavioural consequences • patients fail to notice events on the contralesional side • Patients behave as if they are blind in the contralesional hemifield but they are not blind

  40. Disorders of Orienting • Lesions to parietal cortex can produce some strange behavioural consequences • patients fail to notice events on the contralesional side • Patients behave as if they are blind in the contralesional hemifieldbut they are not blind

  41. Disorders of Orienting • Called Hemispatial Neglect - patients appear unable to process information in the contralesional hemifield

  42. Disorders of Orienting • Hypothesis: Parietal cortex somehow involved in orienting attention into contralesional space

  43. Disorders of Orienting • Posner and colleagues • Use cue-target paradigm to investigate attentional abilities of parietal lesion patients Contralesional Ipsilesional

  44. Disorders of Orienting invalid- contralesional target Results: Severe difficulty with invalidly cued contralesional target invalid - ispilesional target valid - contralesional target valid - ipsilesional target Results: Valid cue in contralesional field is effective

  45. Disorders of Orienting • Interpretation: • Patients have difficulty disengaging attention from good hemifield so that it can be shifted to contralesional hemifield

  46. Disorders of Orienting • Interpretation: • Patients have difficulty disengaging attention from good hemifield so that it can be shifted to contralesional hemifield • Parietal cortex is somehow involved in disengaging attention

  47. Disorders of Orienting • Disengage - Shift - Engage Model • Parietal Cortex notices events and disengages attention

  48. Disorders of Orienting • Disengage - Shift - Engage Model • Parietal Cortex notices events and disengages attention • Superior Colliculus moves attention

  49. Disorders of Orienting • Disengage - Shift - Engage Model • Parietal Cortex notices events and disengages attention • Superior Colliculus moves attention • Pulvinar Nucleus reengages attention

More Related