Download - Reminder your exam is open! You have until Thursday night to take it!

Reminder your exam is open!

You have until Thursday night to take it!

Next Tuesday

• Read article by Anne Treisman

Attention

Information Theory

• Donald Broadbent - earliest systematic investigations of selective attention

•First principle of human information processing: capacity is limited

Information Theory

• Donald Broadbent - earliest systematic investigations of selective attention

Second principle of human information processing: information sources can be selected

Stages of Selection

• Broadbent: Early Selection - a bottleneck exists early in the course of sensory processing that filters out all but the attended channel

• Alternative theory: Late Selection - the bottleneck exists not at the lowest stages, but at the highest - such as response planning, memory and consciousness

Stages of Selection

• Shadowing Task: ignore one input, repeat back the other

• Subjects are largely unaware of unshadowed message but…

• Certain words such as their name distract them!?

• Why is this puzzling?

Orienting Attention

Control of Attention

• Major Distinctions:

Voluntary Reflexive

Control of Attention

• Major Distinctions:

Voluntary Reflexive

Overt Covert

Voluntary Orienting

• Attention can be oriented covertly – a commonly used metaphor is “the spotlight of attention”

Orienting Attention

• Posner Cue - Target Paradigm:

Subject presses a button as soon as x appears

Orienting Attention


Orienting Attention


X

Orienting Attention


Orienting Attention


That was a validly cued trial because the x appeared in the box that flashed

Orienting Attention


Orienting Attention


X

Orienting Attention


Orienting Attention


That was an invalidly cued trial because the x appeared in the box that didn’t flash

Orienting Attention

• Difference in response time (RT) or accuracy (%) is taken to indicate cost of having to reorient attention

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

• Contrast this to voluntary goal-directed orienting

• Is the Posner Cue-Target Paradigm testing reflexive or voluntary attention?

Transients

Reflexive Orienting

• The Posner cueing paradigm (with blinking boxes) confounds reflexive and voluntary orienting

Reflexive Orienting


• How could we change the Posner cueing paradigm to make it assess only reflexive orienting?

Reflexive Orienting



• Make validity 50% (non-informative cue)

Reflexive Orienting



• Make validity 50% (non-informative cue)

• Viewers are still faster and more accurate!

Voluntary Orienting

• What is another way to make this paradigm a voluntary orienting paradigm?

Symbolic cues may orient attention towards another location.Stimulus cues orient attention to the stimulated location.

Symbolic Cue

Reflexive Orienting

• Can symbolic cues be reflexive?

Almost never but …

Reflexive Orienting

• Can symbolic cues be reflexive?

Reflexive orienting to direction of eye gaze – this symbolic cue works even when uninformative