1. Reminder
Starting this week and continuing until the end of the quarter, my office hour will be:
Tuesday 1:30 - 2:30, Guthrie 215
The old, obsolete time was Tuesday 2:30 - 3:30.

2. Early and Late Selection Models of Attention Spatial Attention and Object-Based Attention
Psychology 355: Cognitive Psychology Instructor: John Miyamoto 4/12/2016: Lecture 03-2
Note: This Powerpoint presentation may contain macros that I wrote to help me create the slides. The macros aren’t needed to view the slides. You can disable or delete the macros without any change to the presentation.

3. Lecture probably ends here
Outline
Broadbent's early selection model - evidence pro & con
Semantic evidence for a late selection model
Cognitive resource demands and early versus late selection in attention
Spatial attention and object-based attention
Unilateral neglect - a pathology of attention
Next lecture - Object-based attention
Lecture probably ends here
Recap: “Shadowing”
Psych 355, Miyamoto, Spr ‘16

4. "Shadowing" During Dichotic Listening Study
Dichotic Listening Listening with 2 ears Monotic Listening Listening with 1 ear
"Shadowing" Subject is instructed to repeat out loud the message(s) in one ear, e.g., left ear only.
Results for Shadowing
Psych 355, Miyamoto, Spr '16

5. Shadowing While Engaged in Dichotic Listening: Results
Participants could not report the content of the message in unattended ear
Knew that there was a message, but had no idea what it was
Knew the gender of the speaker
Did not know that the same word was repeated 35 times
Unattended ear is being processed at some level
Cocktail party effect
Change in gender is noticed
Change to a tone is noticed
How to explain the lack of awareness regarding information in the unattended ear?
Attentional Filter – What Is It?
Psych 355, Miyamoto, Spr '16

6. Attentional Filter Filter Inputs
Filter Hypothesis: There is a cognitive mechanism called a "filter" that allows some sensory inputs to pass to deeper levels of processing, and blocks other inputs from continued processing.
Where is the attentional filter in the cognitive process?
Early selection model: Broadbent’s filter model
Intermediate selection model: Treisman’s attenuation theory
Late selection model: McKay (1973)
Filter
Inputs
Early filter models assume that attentional selection precedes the extraction of meaning. So early selection models must distinguish between inputs based on physical features like which ear has the sound, or color.
Broadbent's Filter Model: An Early Selection Theory
Psych 355, Miyamoto, Spr '16

7. Broadbent's (1958) Filter Model (Early Selection Model)
Messages:
Sensory memory
Filter:
Detector:
Short-Term Memory
Broadbent's Filter Model – Messages & Sensory Memory
Psych 355, Miyamoto, Spr '16

8. Broadbent's (1958) Split-Scan Experiment1. H M
Trials 1, 2 & 3 occur in rapid succession.
Cond 1: Report letters in any order.
Typical Result: Subjects says: "M, R, W", then "H, S, P".
65% correct
Cond 2: Report letter pairs for each trial (trial 1, then trial 2, then trial 3)
TypicalResult: Subjects says: "M, H", "R, S", "W, P".
20% correct.
Subjects say Cond 2 is more difficult than Cond 1. 2. S R 3. P W
How does Broadbent's filter model explain this pattern of results?
Psych 355, Miyamoto, Spr '16

9. How does Broadbent's (1958) filter model explain this pattern of results?
Switching attention requires a change (retuning) of the filter. This takes time and cognitive effort.
Cond 1 requires 1 switch of attention;
Cond 2 requires 5 switches of attention. Therefore Cond 2 is harder (more errors; feels more difficult).
NOTE: Later research has shown that the cognitive process is more complex. This example only illustrates how a Broadbent’s Filter Model explains the findings of the split scan experiment. P W S R H M
Problems with Broadbent's Filter Model
Psych 355, Miyamoto, Spr '16

10. Problems with Broadbent's Filter Model
Problems with Broadbent’s filter model are due to the assumption of early selection (selection precedes the extraction of meaning).
Cocktail Party Phenomenon: People remember hearing their own name even if it is presented in the unattended ear.
Broadbent's filter model says that unattended messages are completely blocked. Cocktail Party Phenomenon should not occur.
Gray & Wedderburn's (1960): "Dear Aunt Jane" experiment
Grey & Wedderburn – Dear Aunt Jane Experiment
Psych 355, Miyamoto, Spr '16

11. Gray & Wedderburn's (1960) "Dear Aunt Jane" Experiment
Subject is told to report what you hear in your LEFT ear.
Correct response: "Dear, 7, Jane"
Typical response: "Dear Aunt Jane"
If Broadbent's filter is all-or-none, then subjects should give correct response.
Conclusion: Subjects extract some meaning from the message in the unattended ear. Broadbent's filter must leak!
Dear 9 7
Aunt
Jane 6
Return to Problems with Broadbent's Filter Model
Psych 355, Miyamoto, Spr '16

12. Problems with Broadbent's Filter Model
Cocktail Party Phenomenon: People remember hearing their own name even if it is presented in the unattended ear.
Broadbent's filter model says that unattended messages are completely blocked. Cocktail Party Phenomenon should not occur.
Participants track meaningful messages that switch from one ear to another even when they are not supposed to do this. Gray & Wedderburn's (1960): "Dear Aunt Jane" experiment
Effects of practice on detecting information in unattended ear
You can be trained to detect information in the unattended ear (based on the meaning of the message)
Treisman Attenuation Model
Psych 355, Miyamoto, Spr '16

13. Treisman's Attenuation Model
The attenuator intensifies the attended message, and weakens (attenuates) the unattended message.
The attenuator analyzes information in terms of (a) physical characteristics and (b) linguistic form, e.g., sentence structure.
Dictionary Unit detects words according to importance,
Words in the attended channel automatically get a boost in importance.
Word in unattended channels can still get through if words in these channels have sufficient importance.
Explain how attenuation model explains Cocktail Party Phenomenon.
Explain how attenuation model explains "Dear Aunt Jane" experiment.
MacKay's Late Selection Model
Psych 355, Miyamoto, Spr '16

14. Evidence for Late Selection (MacKay, 1973)
Subjects told to attend to left ear.
All sentences in left ear were ambiguous.
Word in right ear suggests one of two interpretations for ambiguous sentence.
They threw stones at the bank
Money
They threw stones at the bank
River
Example of a Question Asked to the Subjects
Psych 355, Miyamoto, Spr '16

15. Evidence for Late Selection (MacKay, 1973)
Subjects were asked: Which sentence is closer to the meaning of a sentence that you heard?
They threw stones at the savings and loan association.
They threw stones towards the side of the river.
Finding: Word in right ear biases interpretation of sentence in left ear.
They threw stones at the bank
Money
Result is hard to explain if selection preceeds extraction of meaning from input.
They threw stones at the bank
River
Diagram of Early vs Late Selection Models & Attenuator Model
Psych 355, Miyamoto, Spr '16

16. Before Extraction of Meaning After Extraction of Meaning
Contrast Between Early Selection, Attenuator, and Late Selection Models
Before Extraction of Meaning
Extraction of Meaning
After Extraction of Meaning
Early Selection
Attenuator
Late Selection
Text Version that Contrasts Early, Intermediate & Late Selection Models
Psych 355, Miyamoto, Spr '16

17. Contrast Between Early, Intermediate, and Late Selection Models
This slide is pretty much the same as the preceding slide, except that the information is stated verbally.
Early selection models:
Attentional selection is based exclusively on physical characteristics of the signal.
Attentional selection cannot be based on meaning of signal
Unattended signals (messages) are completely blocked
Intermediate selection model (attenuator model)
Unattended signals (messages) are weakened (attenuated), not blocked
Late selection models
Attentional selection can be based on meaning as well as on physical characteristics of the signal
Unattended signals are only partially blocked
Which Is Correct? Early or Late Selection?
Psych 355, Miyamoto, Spr '16

18. Which is Correct, Early Selection or Late Selection?
Evidence shows that the correct model depends on the nature of the task.
Some tasks force the human to filter information at an early stage of information processing.
Other tasks allow the human to filter information at later stages of information processing.
Next slide clarifies the issues between early, intermediate and late selection models.
Is Attention a Divisible Cognitive Resource?
Psych 355, Miyamoto, Spr '16

19. Is Attention a Divisible Cognitive Resource?
Hypothesis: Attention is like a finite cognitive resource. We can use up some of it, or all of it, on any given task.
Figure 4.7 Left (low cognitive load):
Low demand task leaves excess attention to wander to irrelevant stimuli.
Figure 4.7 Right (high cognitive load):
High demand task requires 100% of attention. Irrelevant stimuli are ignored.
Figure 4.7. Attention as a Finite Cognitive Resource
Remaining cognitive resources
No cognitive resources remain
Resources used by low-load primary task
Resources used by high-load primary task
Influence of Cognitive Load on Early vs Late Selection
Psych 355, Miyamoto, Spr '16

20. Influence of Cognitive Load on Early versus Late Selection
Figure 4.7 Left:
Low demand task leaves excess attention to process meaning of irrelevant stimuli.
When subjects are affected by meaning of irrelevant stimuli, results support late selection models.
Therefore low demand task should produce results that support late selection.
Figure 4.7 Right:
High demand task requires 100% of attention.
There is no excess attention to process meaning of irrelevant stimuli.
Therefore high demand task should produce results that support early selection.
Figure 4.7. Attention as a Finite Cognitive Resource
Remaining cognitive resources
No cognitive resources remain
Resources used by low-load primary task
Resources used by high-load primary task
Table Showing Experimental Design for Testing This Hypothesis
Psych 355, Miyamoto, Spr '16

21. Tuesday, April 12, 2016: The Lecture Ended Here
Psych 355,, Miyamoto, Spr '16

22. Fig. 4.7: [Easy or Hard] x [Distractor Present or Absent]
Goldstein Figure Detection task was EASY or HARD. Distractor (dog face) was ABSENT (Panel a) or PRESENT (Panel b)
TASK:
Say "N" if "N" is present.
Say "Z" if "Z" is present.
EASY
HARD
Distractor ABSENT
Distractor PRESENT
EASY Condition: Distractor stimuli are "o". HARD Condition: Distractor stimuli are similar to "N" and "Z".
Distractor ABSENT (a): No dog face in the display Distractor PRESENT (b): Irrelevant dog face in the display
Psych 355, Miyamoto, Spr '16

23. Fig. 4.7: [Easy or Hard] x [Distractor Present or Absent]
Goldstein Figure Detection task was EASY or HARD. Distractor (dog face) was ABSENT (Panel a) or PRESENT (Panel b)
TASK:
Say "N" if "N" is present.
Say "Z" if "Z" is present.
EASY
HARD
Distractor ABSENT
Distractor PRESENT
EASY Condition: Distractor stimuli are "o". HARD Condition: Distractor stimuli are similar to "N" and "Z".
Distractor ABSENT (a): No dog face in the display Distractor PRESENT (b): Irrelevant dog face in the display
Psych 355, Miyamoto, Spr '16

24. Fig. 4.7: [Easy or Hard] x [Distractor Present or Absent]
Panel (b) on right:
Grey tops to bars show how much the distractor (dog face) slowed down the RT.
Distractor had greater influence in EASY condition.
Goldstein Figure Detection task was EASY or HARD. Distractor (dog face) was ABSENT (Panel a) or PRESENT (Panel b)
Interpretation: Subjects had more excess attention to divert to distractor when the task was EASY.
Results Support Hypothesis: Attention is Divisible Resource
Psych 355, Miyamoto, Spr '16

25. Results Support Hypothesis: Attention a Divisible Cognitive Resource
Hypothesis: Attention is like a finite cognitive resource. We can use up some of it, or all of it, on any given task.
Figure 4.7 Left (low cognitive load):
Low demand task leaves excess attention to wander to irrelevant stimuli.
Figure 4.7 Right (high cognitive load):
High demand task requires 100% of attention. Irrelevant stimuli are ignored.
Goldstein’s Figure 4.8. Attention as a Finite Cognitive Resource
Remaining cognitive resources
No cognitive resources remain
Resources used by low-load primary task
Resources used by high-load primary task
Video Game Study
Psych 355, Miyamoto, Spr '16

26. Study of Novice & Expert Video Game Players
Low Load (easy game): Both novices and experts are affected by irrelevant stimuli.
High Load (difficult game): Experts are affected by irrelevant stimuli; novices are not affected.
Cognitive load has to be defined in terms of the difficulty of the task for a particular individual (it can vary from one person to the next).
Conjecture (Invisible Gorilla Experiment): If subjects were trained to count passes and bounces (became "experts"), then they would notice the gorilla.
Conclusions: Early vs Late Selection Depends on Available Excess Attention
Psych 355, Miyamoto, Spr '16

27. Conclusions: Early versus Late Selection Models
Main Question: Where in the cognitive process does attentional selection occur? Early? Late? In between?
Some kinds of tasks provide evidence for early selection.
Other tasks provide evidence for late selection.
There is evidence that early selection occurs with hard tasks; Late selection occurs with easy tasks.
(Remember the issue in early versus late selection is the question whether attentional selection occurs before or after the assignment of meanings to stimuli.)
Results suggest that we can treat attention like it is a divisible cognitive resource.
Define Spatial Attention
Psych 355, Miyamoto, Spr '16

28. Spatial Attention – What Is It?
█ ▲
Fixation Point
It is possible to attend to either the red rectangle or the blue triangle while maintaining eye fixation at the +.
Spatial attention is attention to different locations in visual space.
Monkey Experiment - Neuropsych Evidence for Spatial Attention
Psych 355, Miyamoto, Spr '16

29. Monkey Attention Experiment (Colby, Duhamel, Goldberg, 1995)
Fixation Point
Peripheral Stimulus
BOTH CONDITIONS: Monkey holds down a bar while fixating the fixation point. Monkey is rewarded if he releases the bar at the “right” moment.
FIXATION ONLY CONDITION: When the fixation point dims, the monkey must release the bar.
FIXATION & ATTENTION CONDITION: When the peripheral stimulus dims, the monkey must release the bar.
Single-Cell Recording in Monkey Parietal Cortex
Psych 355, Miyamoto, Spr '16

30. Single-Cell Recording in Monkey Parietal Cortex
FIXATION ONLY
FIXATION & ATTENTION
Firing Rate
Firing Rate
Also there is human fMRI evidence for spatial attention. Activity is found especially in parietal cortex, but also temporal cortex and frontal cortex. See Goldstein textbook, Fig. 4.38, p. 108.
Recording is made during the period while monkey is waiting for the signal to respond.
The stimulus is the same for the left & right graph, but the monkey is attending to the peripheral location on the right.
Results constitute neuropsychological evidence for spatial attention (attention to the location of the peripheral stimulus).
Unilateral Neglect & Spatial Attention
Psych 355, Miyamoto, Spr '16

31. Unilateral Neglect – A Pathology of Attention
Unilateral Neglect: A deficit of attention in which one entire half of a visual scene is simply ignored. (Discussed in Goldstein Chapter 10)
The cause of unilateral neglect is often a stroke that has interrupted the flow of blood to the right parietal lobe.
Figure to the right: Patient’s copy of an image (model) shows systematic deficits.
This slide is based on instructional material that was downloaded from the Pearson Publishers website ( for Smith & Kosslyn (2006; ISBN ).
The patient’s copy in the right column neglects the left side of the visual field (opposite to the side of brain damage).
Brain Diagram - Locate Parietal Lobe
Psych 355, Miyamoto, Spr '16

32. Left Hemisphere: Note Location of Parietal Cortex
Head is facing LEFT
Unilateral neglect is associated with injury to the left or right parietal cortex.
Behavioral Differences Between Left & Right Parietal Injuries
Psych 355, Miyamoto, Spr '16

33. More Examples of Unilateral Neglect
Brain scan of patient showing right parietal damage (head faces up)
Drawings made by patient.
Patient instructed to put a crossing line through every line.
Large Diagram of the Lobes of the Brain
Psych 355, Miyamoto, Spr '16

34. Left versus Right Parietal Injury
Right: Figure 3.16 from Anderson (2005).
Patients with left or right parietal injuries were asked to copy the figure in column A.
Right injury: Small parts were correct – general form was not.
Left injury: General form was correct – small parts were not..
C: Left Parietal Injury
A: Model to be Copied
B: Right Parietal Injury
Same Slide With Red Emphasis Rectangles On Each Row of Drawings
Psych 355, Miyamoto, Spr '16

35. Left versus Right Parietal Injury
Right: Figure 3.16 from Anderson (2005).
Patients with left or right parietal injuries were asked to copy the figure in column A.
Right injury: Small parts were correct – general form was not.
Left injury: General form was correct – small parts were not.
Illustrates specialization in the left and right parietal lobe for particular aspects of attention.
C: Left Parietal Injury
A: Model to be Copied
B: Right Parietal Injury
Same Slide Without the Red Emphasis Rectangles
Psych 355, Miyamoto, Spr '16

36. Left versus Right Parietal Injury
Right: Figure 3.16 from Anderson (2005).
Patients with left or right parietal injuries were asked to copy the figure in column A.
Right injury: Small parts were correct – general form was not.
Left injury: General form was correct – small parts were not.
Illustrates specialization in the left and right parietal lobe for particular aspects of attention.
C: Left Parietal Injury
A: Model to be Copied
B: Right Parietal Injury
Summary So Far - END
Psych 355, Miyamoto, Spr '16

37. Summary So Far
Pathologies of attention demonstrate multiple functional components to attention.
Attention to left or right visual field.
Attention to global perceptual structure versus attention to smaller details
Problems with attention switching – perseveration
Problems with attending to objects (Balint's syndrome)
Is visual attention always equivalent to attention to locations? Results from object based attention show that the answer is “no”! (later)
END
Psych 355, Miyamoto, Spr '16

38. Set Up for Instructor
Turn off your cell phone. Close web browsers if they are not needed.
Classroom Support Services (CSS), 35 Kane Hall,
If the display is odd, try setting your resolution to 1024 by 768
Run Powerpoint. For most reliable start up:
Start laptop & projector before connecting them together
If necessary, reboot the laptop
Psych 355, Miyamoto, Spr ‘16