1. Cognitive Processes PSY 334
Chapter 3 – Attention

2. What is Attention?
Attention is the allocation of limited processing resources.
Visual features such as shape, color, texture, motion are processed in parallel.
Serial bottleneck – occurs when it is no longer possible to process in parallel.
When does it occur – early vs late selection
How do we select what to attend to?

3. How we Experience Attention
Stream of consciousness -- we learn and remember what we attend to.
Paying attention results in a feeling of mental effort.
Can be directed internally but also pulled (attracted) by external events.
Varies with arousal and fatigue.
Studied by looking at response competition.

4. Auditory Attention
The response competition comes from having two ears.
Dichotic listening task – uses “shadowing.”
Two different messages are presented, one to each ear. Subjects are asked to speak what they hear.
People can attend to only one message at a time.

5. Broadbent’s Filter Theory
People do not remember the content of the unattended ear.
Voice or noise, sex, but little else.
Broadbent’s filter theory proposed that filtering occurs early in processing based on physical characteristics (pitch, ear).
Neural evidence supports the ability to select one ear to listen to.
Cocktail party effect – attention switches based on content of unattended ear.

6. Treisman’s Attenuation Theory
Treisman’s attenuation theory – subjects deemphasize but not filter out the unattended message.
Meaning switched from one ear to the other.
Some subjects switch ears even when told not to, following the semantic content.
Semantic criteria apply to all messages, filtered or not.

7. Late Selection Theory
Deutsch & Deutsch’s late selection theory – the limitation is in the response system, not the perception.
Both messages are perceived but only one can be shadowed at a time.
The criterion for selecting what to say can change – based on ear or meaning.

8. Testing the Theories Dichotic listening task:
Shadow one message but listen for a target word in both ears (tap when heard).
Late selection theory predicts no difficulty hearing the target in either ear.
Attenuation theory predicts less detection in non-shadowed ear.
87% detection in shadowed ear
8% detection in non-shadowed ear

9. Echoic Memory
Glucksberg & Cowen demonstrated that unattended information can be kept in an echoic memory buffer for brief periods.
Shadow a message, with digit presented to non-shadowed ear.
25% of time, is asked immediately after presentation, reported hearing the digit.
5% of time reported the digit, without cuing
Unattended material is lost within 5 seconds.

10. Visual Attention
We can choose where to fixate our eyes for greatest visual acuity.
Other portions of the visual field are attenuated.
Visual attention need not be located where the eyes are fixed.
Posner – subjects can attend to objects up to 24 degrees from the fovea.
Shift of attention precedes eye movement.

11. Spotlight Metaphor
Spotlight can be broad or narrow (degrees of visual angle).
Broad areas processed less well.
A narrow focal point gives optimal processing but it takes time to move the focus to other areas of the visual field.
We move our eyes around a complex visual stimulus.
Neisser & Becklen’s shadowing task.