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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.
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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 • Posner Cue - Target Paradigm: X
Orienting Attention • Posner Cue - Target Paradigm:
Orienting Attention • Posner Cue - Target Paradigm: That was a validly cued trial because the x appeared in the box that flashed
Orienting Attention • Posner Cue - Target Paradigm:
Orienting Attention • Posner Cue - Target Paradigm:
Orienting Attention • Posner Cue - Target Paradigm:
Orienting Attention • Posner Cue - Target Paradigm: X
Orienting Attention • Posner Cue - Target Paradigm:
Orienting Attention • Posner Cue - Target Paradigm: That was an invalidly cued trial because the x appeared in the box that didn’t flash
Paradigms Used To Study Attention • Posner Cue - Target Paradigm: Attention Effect = Valid RT - Invalid RT
Voluntary Orienting • Under what circumstances would a cue lead to a voluntary shift of attention?
Voluntary Orienting • Under what circumstances would a cue lead to a voluntary shift of attention? • Informative cue • Validity = greater than 50%
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?
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.
Voluntary Orienting • What is the time course of voluntary orienting? Invalidly Cued Targets Response Time Validly Cued Targets Cue - Target Interval About 200 ms
Reflexive Orienting • Attention can be automatically “summoned” to a location at which an important event has occurred:
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
Reflexive Orienting • The Posner cueing paradigm (with blinking boxes) confounds reflexive and voluntary orienting … in what way?
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?
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)
Reflexive Orienting • Time course of reflexive orienting is counterintuitive Response Time Valid Invalid 0 500 1000 About 50 ms Cue - Target Interval (ms)
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)
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
Reflexive Orienting • Can symbolic cues be reflexive? Almost never but …
Reflexive Orienting • Can symbolic cues be reflexive? Reflexive orienting to direction of eye gaze
Reflexive Orienting • Potential cues for Reflexive Orienting • Loud noise • Motion • New Object • New Objects are powerful attention grabbers! Transients
New Objects Capture Attention IS THERE AN “H”? Initial scene viewed for several hundred ms Yantis & Jonides (1990): New-Object Paradigm
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
Reflexive Orienting • Steven Yantis and colleagues • Result:
Reflexive Orienting • Steven Yantis and colleagues • Result: Targets are found faster when they are “new objects” than when they are revealed from “old” objects
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
Physiology of Attention • Neural systems involved in orienting • Neural correlates of selection
Disorders of Orienting • Lesions to parietal cortex can produce some strange behavioural consequences Parietal Lobe
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
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
Disorders of Orienting • Called Hemispatial Neglect - patients appear unable to process information in the contralesional hemifield
Disorders of Orienting • Hypothesis: Parietal cortex somehow involved in orienting attention into contralesional space
Disorders of Orienting • Posner and colleagues • Use cue-target paradigm to investigate attentional abilities of parietal lesion patients Contralesional Ipsilesional
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
Disorders of Orienting • Interpretation: • Patients have difficulty disengaging attention from good hemifield so that it can be shifted to contralesional hemifield
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
Disorders of Orienting • Disengage - Shift - Engage Model • Parietal Cortex notices events and disengages attention
Disorders of Orienting • Disengage - Shift - Engage Model • Parietal Cortex notices events and disengages attention • Superior Colliculus moves attention
Disorders of Orienting • Disengage - Shift - Engage Model • Parietal Cortex notices events and disengages attention • Superior Colliculus moves attention • Pulvinar Nucleus reengages attention