CONTENT CALENDAR
1. Tuesday 6 March: Intro & Basic Foundations
2. Thursday 8 March: Run an Experiment, Designing Computerized Experiments & Methods in Papers
3. Tuesday13 March: Classic Experiment 1: Attention & Interference
4. Thursday15 March: Classic Experiment 2: Spatial Attention
5. Tuesday 20 March: Classic Experiment 3: Divided & Selective Attention
6. Thursday 22 March: Experimental Design Proposal
7. Tuesday 27 March: Classic Experiment 4: Memory & Response Inhibition
8. Thursday 5 April: Classic Experiment 5: Embodiment & Sense of Self
9. Tuesday10 April: 14.30-18.30. Kinematic Data Acquisition
10. Thursday12 April: Summary & Test 1 EXPERIMENTAL DESIGN PROPOSAL
. Small groups of 4/5 people (for 5/6 groups in total)
. Select one or more relevant recent papers you’d like to focus on
. Upload the paper(s) on e-learning
. Try to review with a critical attitude the method
. Design an original experiment (theoretical impact not essential)
. Describe and list all the relevant variables, the timeline and the general procedure
. Prepare a (visual) PowerPoint presentation
. Present your own experiment in 10/15 minutes maximum (each person of the group should present an equal part), plus discussion from all the class group
2 THE XXXXXX EFFECT
MEASURING ATTENTION & INTERFERENCE
LESSON 3
LAB: COGNITIVE AND BEHAVIORAL MEASURES
Luca Rinaldi
3 THE XXXXXX EFFECT
• He received a PhD in experimental psychology from George Peabody College in 1932.
• His dissertation, published in The American Journal of Experimental Psychology in 1935, focused on studies in interference and attention.
• This study developed into a test that has since become foundational for the field of cognitive psychology.
John Ridley Stroop
4 THE STROOP EFFECT
6 THE STROOP EFFECT
A page from Stroop’s original materials for his experiments
7 THE STROOP EFFECT
Stroop did not just use words to test his hypothesis; he also used shapes like these to see if the same interference appeared in both cases
8 THE STROOP EFFECT
In its basic form, the task is to name the color in which a word is printed, ignoring the word itself:
Name and color correspond
RED GREEN BLUE PINK
ORANGE BLUE GREEN WHITE
GREEN YELLOW ORANGE WHITE
BROWN RED BLUE GREEN
PINK YELLOW GREEN RED
9 THE STROOP EFFECT
In its basic form, the task is to name the color in which a word is printed, ignoring the word itself:
Name and color do not correspond (1)
RED GREEN BLUE PINK
ORANGE BLUE GREEN WHITE
GREEN YELLOW ORANGE WHITE
BROWN RED BLUE GREEN
PINK YELLOW GREEN RED
10 THE STROOP EFFECT
In its basic form, the task is to name the color in which a word is printed, ignoring the word itself:
Name and color do not correspond (2)
TOWN CUP BELT PEN
SCARF BELT CUP CLOCK
CUP APPLE SCARF CLOCK
SHOES TOWN BELT CUP
PEN APPLE CUP TOWN
11 DIFFERENT CONDITIONS
Which is the pattern of RTs you would guess on?
Correspond Not correspond (1) Not correspond (2)
RED RED TOWN
ORANGE ORANGE SCARF
GREEN GREEN CUP
BROWN BROWN SHOES
PINK PINK PEN
11 DIFFERENT CONDITIONS
Which is the pattern of RTs you would guess on?
Congruent Incongruent Neutral Neutral (2)
RED RED TOWN
ORANGE ORANGE SCARF
GREEN GREEN CUP
BROWN BROWN SHOES
PINK PINK PEN
12 PATTERN OF RTS
Which is the pattern of RTs you would guess on?
)
ms
(
RTs 400 400 600 800 1000
Incongruent Neutral Congruent
Duncan-Johnson & Kopell, 1981
13 PERFORMANCE COST
The performance cost in the mismatch condition – usually referred to as the incongruent condition – relative to the controls is called the Stroop effect or Stroop interference
measure the interference of one stimulus dimension on another.
14 PERFORMANCE COST
How would you actually compute cognitive interference? What is essential and what’s not?
15 PERFORMANCE COST
How would you actually compute cognitive interference? What is essential and what’s not? PD
Controls
)
ms
(
RTs 400 400 600 800 1000
Incongruent Henik, 1996
16 PERFORMANCE COST
From Lesson 2
17 PERFORMANCE COST
How would you actually compute cognitive interference? What is essential and what’s not? PD
Controls
)
)
ms
ms
(
Delta ( Delta
RTs
400 400 600 800 1000 50 100 150 200
Incongruent Neutral Delta Henik, 1996
18 PERFORMANCE COST
How would you actually compute cognitive interference? What is essential and what’s not? PD
Controls )
ms Which kind of analysis would you actually carry (
on?
RTs 400 400 600 800 1000
Incongruent Neutral Henik, 1996
19 PERFORMANCE COST
How would you actually compute cognitive interference? What is essential and what’s not? PD
2x2 Mixed ANOVA: Controls Group (PD, Controls) x Condition (Neutral, Incongruent)
Henik, 1996
20 PERFORMANCE COST
How would you actually compute cognitive interference? What is essential and what’s not? PD
2x2 Mixed ANOVA: Controls Group (PD, Controls) x Condition (Neutral, Incongruent)
Main effect of Group and Condition No significant Interaction
Not significant
Henik, 1996
21 PERFORMANCE COST
How would you actually compute cognitive interference? What is essential and what’s not?
Interference is the difference between the incongruent condition and the neutral condition (or congruent one)
Interference = Incongruent – Neutral (Congruent)
22 STANDARD PROCEDURE
An intriguing feature of the Stroop literature, though, is that there was virtually no follow-up to his work for about 30 years
It is only in the 1960s that research on this phenomenon resumed and then with a vengeance
The simplest explanation of this is that the advent of computer-controlled experiments, and especially the resulting ability to time individual trial stimuli, opened up a rich new realm of investigation for which the Stroop task was ideally suited
23 STANDARD PROCEDURE
Trial by trial presentation, with RTs for each stimulus
500 ms +
Until response BLUE (max 2000 ms)
24 EXPLANATION
Do you have any idea of why interference is occurring?
Speed of Processing Theory Selective Attention Theory
25 SPEED OF PROCESSING THEORY
. Faster processes can affect slower processes
. Slower processes cannot affect faster processes
if the wrong dimension of a stimulus is processed prior to the right dimension (where right and wrong are denned by task demands), interference will result
26 SPEED OF PROCESSING THEORY
. Faster processes can affect slower processes
. Slower processes cannot affect faster processes
From Lesson 1
27 SPEED OF PROCESSING THEORY
. Faster processes can affect slower processes
. Slower processes cannot affect faster processes
RED
28 SPEED OF PROCESSING THEORY
. Faster processes can affect slower processes
. Slower processes cannot affect faster processes
RED
RED
29 SPEED OF PROCESSING THEORY
. Faster processes can affect slower processes
. Slower processes cannot affect faster processes
How would you demonstrate this?
30 SPEED OF PROCESSING THEORY
. Faster processes can affect slower processes
. Slower processes cannot affect faster processes
By asking participants to read words (and not name the ink)!
From Stroop’s original experiment
31 PATTERN OF RTS
Which is the pattern of RTs you would guess on?
Color naming
)
ms
(
RTs 400 400 600 800 1000
Incongruent Neutral Congruent
Duncan-Johnson & Kopell, 1981
32 PATTERN OF RTS
Which is the pattern of RTs you would guess on?
Color naming
Word reading
)
ms
(
RTs 400 400 600 800 1000
Incongruent Neutral Congruent
Duncan-Johnson & Kopell, 1981
33 SPEED OF PROCESSING THEORY
. Faster processes can affect slower processes
. Slower processes cannot affect faster processes
RED
RED
34 SPEED OF PROCESSING THEORY
. Faster processes can affect slower processes
. Slower processes cannot affect faster processes
This effect is basically explained by our amount of reading experience, and thus by the difference in training in the two activities
35 LIMITS
. Reading was made increasingly difficult by manipulating orientation uncertainty
Dunbar & MacLeod, 1984
even when reading a color word was considerably slower than naming the color of ink in which the word was printed, Stroop interference persisted virtually unaltered
36 EXPLANATION
Do you have any idea of why interference is occurring?
Speed of Processing Theory Selective Attention Theory
37 SELECTIVE ATTENTION THEORY
. The Stroop effect depends on specific circumstances and, specifically, on response set selection
. Response set refers to selection on the basis of the vocabulary of eligible responses
A major part of the interference caused by incongruent stimuli is specific to the members of the response set
38 SELECTIVE ATTENTION THEORY
. Color words that are eligible responses produced approximately two times more interference than did color words that are not used as responses in the experiment
GREEN BLUE
Greater interference Lower interference Glaser & Glaser, 1989; Proctor, 1978
39 SELECTIVE ATTENTION THEORY
. Color words that are eligible responses produced approximately two times more interference than did color words that are not used as responses in the experiment
GREEN BLUE
GREEN RTs
BLUE RED
Glaser & Glaser, 1989; Proctor, 1978 Incongruent Congruent 40 SELECTIVE ATTENTION THEORY
. The Stroop effect depends on specific circumstances and, specifically, on response set selection
. Response set refers to selection on the basis of the vocabulary of eligible responses
After broad activation, selective attention is directed only to relevant processes
41 SELECTIVE ATTENTION THEORY
. The Stroop effect depends on specific circumstances and, specifically, on response set selection
. Response set refers to selection on the basis of the vocabulary of eligible responses
Selective attention BLUE Inhibitory processes
RED GREEN
42 THE STROOP EFFECT
MAIN APPLICATIONS
LESSON 3
LAB: COGNITIVE AND BEHAVIORAL MEASURES
Luca Rinaldi
43 APPLICATIONS
. In essence, Stroop’s paradigm provides a template for studying interference
investigators have often mined that template to create Stroop-like tasks suited to their particular research purposes.
Any guess?
44 APPLICATIONS
. In essence, Stroop’s paradigm provides a template for studying interference
investigators have often mined that template to create Stroop-like tasks suited to their particular research purposes.
HORSE LEFT
6 6 HTH 6 6
45 APPLICATIONS
. Picture-word interference task: a conflicting word is embedded in a picture
Similar effect in children and adults
Rosinski et al., 1975 50% congruence 46 APPLICATIONS
. Directional version: substantial interference from the embedded word when identifying the direction of the arrow
Congruent
LEFT RIGHT
Incongruent
RIGHT LEFT
For both horizontal and vertical axes
Shor et al., 1972
47 APPLICATIONS
. Digit-version: counting the number of digits is impaired when the digits themselves are incompatible with their numerosity
Congruent 4 6 4 6 6 4 4 6 6 6
Incongruent
4 6 4 6 4 6 4 6 4 4 Similar effect in children and adults
Rosinski et al., 1975
48 APPLICATIONS
. Numerical Stroop effect: demonstrates the relationship between numerical values and physical sizes
Similar effect for both judgments Numerical comparison task Henik & Tzelgov, 1982
49 THE EMOTIONAL STROOP EFFECT
. The emotional Stroop task is assumed to tap the interference from emotionally valent though irrelevant information on a simple task (Willliams et al., 1996)
. As in the classic Stroop task, words are presented and participants have to name the ink of the color
50 THE EMOTIONAL STROOP EFFECT
. The emotional Stroop task is assumed to tap the interference from emotionally valent though irrelevant information on a simple task (Willliams et al., 1996)
. Words have different valence
Positive Negative Neutral TRUTH FEAR ANGLE
HUMOR PANIC CHAIR
FUN LIE SILENCE
TALENT HATE PAPER
DREAM MURDER CORNER
51 THE EMOTIONAL STROOP EFFECT
. The emotional Stroop task is assumed to tap the interference from emotionally valent though irrelevant information on a simple task (Willliams et al., 1996)
. Words have different valence
)
ms
(
RTs 400 400 600 800 1000
Negative Neutral Positive
52 THE EMOTIONAL STROOP EFFECT
. Selective failure of naming colors induced by the concurrent word meaning
. Used to investigate psychopathology: typically more marked effect in emotionally disturbed people
Mitterschiffthaler et al., 2008
53 SYNESTHESIA
. Syn = together + aisthesis = perceiving «a concomitant sensation»
54 SYNESTHESIA
. Syn = together + aisthesis = perceiving «a concomitant sensation»
. a subjective sensation or image of a sense (as of color) other than the one (as of sound) being stimulated
Synesthesia is a conscious experience of systematically induced sensory attributes that are not experienced by most people under comparable conditions (Grossenbacher & Lovelace, 2001)
55 SYNESTHESIA
. About 4% of the general population
. Most frequent associations between days of the week and colors: in more of 50% of synesthetes (Simner et al., 2006)
56 SYNESTHESIA
. Different types of synesthesia (Cohen-Kadosh & Henik, 2008)
Number-Shape Time-Shape
Color-grapheme
57 SYNESTHESIA
. Synesthesia is composed of two interrelated components (Grossenbacher & Lovelace, 2001)
1. Inducer referring to the inducing event 2. Concurrent referring to the synesthetically induced sensory attribute(s)
One sybesthete descibes the letter A (Inducer) as red colored (Concurrent)
Automaticity: synesthetic concurrents are involuntarily induced
58 EXAMPLE
Perceived by a non-synesthete Perceived by a synesthete
59 PROBING SYNESTHESIA
But how would you probe that this is a real sensation?
60 PROBING SYNESTHESIA
Synesthetes’ reports: A B C D E F G H I 1 2 3 4 5 6 7 8 9 Synesthetes Non-synesthetes Incongruent Neutral Congruent
7 7 7
)
ms
(
RTs 400 400 600 800 1000
Incongruent Neutral Congruent
Mattingley et al., 2001
61 PROBING SYNESTHESIA
Cohen-Kadosh & Henik, 2007
62 INTERPRETATION (1)
Cerebral areas devoted to the Typical cerebral activation + processin of other sensory information
E.g., sound-color synesthesia
Auditory areas Visual areas (V4/V8 for shape and color)
63 INTERPRETATION (1)
Hubbard et al., 2005
64 INTERPRETATION (2)
Cross-activation theory: synesthesia as a result of a genetic mutation that causes defective pruning (Ramachandran & Hubbard, 2001)
Sensorial experience undifferentiated until 4 months
NORMAL DEVELOPMENT SYNESTHESIA
The processing of sensory Incomplete differentiation and information becomes modular strong connections between and brain areas differentiated brain areas
65 INTERPRETATION (2)
Synesthetes Non-Synesthetes
Hanggi et al., 2011
66 SEE YOU NEXT LESSON!
67