A Snake Wiggle of Reaction Time
Functions to Indicate Holistic Perception
Old face
Configurally Features only
Altered
(new) face
Mario Fifić
Grand Valley State University, Michigan
Phenomenon
The “Snake Wiggle” signature
Session 3-4
100
RT ms
150
200
0
50
100
RT ms
150
600
Session 9-10
0.2
0.2
0
SIC
0.2
SIC
0.4
0
0.2
0.2
0.4
0.4
0.4
100
RT ms
150
0
200
50
100
RT ms
150
200
50
SIC
0.2
SIC
0.2
0
0
0.2
0.2
0.2
0.4
0.4
0.4
0
200
50
100
RT ms
150
200
50
100
RT ms
150
200
0.1
HL
2
LH
Lips-position
HL
HH
HH
HL
Freq
Sharks
LL
0.002
0.002
0.001
0.001
LL L
Freq
Jets
HL
HL
0.005
0.005
0.004
0.004
0.003
0.003
0.003
0.003
0.002
0.002
Eye- separation
400.
400.
680
Exterior
660
LH
640
0.1
Interior
200.
200.
0.4
0.2
-
1000. 1200. 1400.
1000. 1200. 1400.
0.2
LL
800.
800.
1000. 1200.
1200. 1400.
1400.
1000.
460
0.0
0
LH
0.6
0.4
0.2
+
LL
0.8
0.6
0.4
=
0.2
1
2
70 80
RT ms
90 100 110
SIC(t) = Shh(t) -
50
60
70 80
RT ms
50
90 100 110
Shl(t)
-
60
70 80
RT ms
90 100 110
50
(Slh(t)
60
70 80
RT ms
Serial
Self-terminating
Input
Eyes
Lips
Decision
OR
Response
B
Serial
Exhaustive
Input
Eyes
Lips
Decision
AND
Response
Decision
OR
Response
Analytic
Analytic/
Holistic
C
Input
Parallel
Self-terminating
LL L
Contrast Category
Input
D
Parallel
Exhaustive
Eyes
Lips
Input
Eyes
Input
Lips
Decision
AND
Response
E
Coactive
Input
Input
Eyes
Lips
Joe’s
face
Decision
Response
Analytic
Analytic/
Holistic
Strong
Holistic
8
10
12
Serial
Block (2 x Session)
model RT[Ext]<RT[Int]
Jets Parallel model RT[Ext]=RT[Int]
Participant Coactive
06
RT[Ext]>RT[Int]
Eye- separation
0.3
-20
-40
4
5
6
7
8
-80
-100
“Coactive”
740
0.2
720
1
2
3
4
5
6
7
8
9
10
700
0.1
680
Snake Wiggle
660
640
0.0
0
2
4
6
8
10 “Parallel”
Block (2 x Session)
Conclusions
0
0.4
0
Architecture flow
diagram
6
0.2
90 100 110
- Sll(t))
3
Block (2 x Session)
0.2
60
0
-60
0.4
0.8
4
Interior
780
20
0.1
RT[Ext]-RT[Int]
RT(ms)
480
S IC
SIC
0.2
-
0.6
Exterior
0.3
1
P R O B A B IL IT Y
0.4
HL
500
600.
600.
LL2 L
(Fific, Little & Nosofsky,
2010; Psych Review)
760
540
400.
400.
0
H
0.0
800
0.001
0.001
200.200.
400.400.
600.600.
800.800.
1000.
1200.
1400.
1000.
1200.
1400.
1
P R O B A B IL IT Y
0.6
P R O B A B IL IT Y
P R O B A B IL IT Y
HH
800.
800.
580
Participant 05
520
RT(ms)
1
600.
600.
Contrast
0.2
Category
LH
Errors
RT(ms)
560
0.002
0.002
0.001
0.001
0.8
10
580
200.
200.
0.3
Sharks
620
LL
HL
Block (2 x Session)
600
0.004
0.004
0.002
0.002
0.004
0.004
0.8
8
0.006
0.006
0.003
0.003
LH
H
6
0.008
0.008
0.006
0.006
0.005
0.005
HL
4
Reaction time histograms
640
620 LH
HHHH
LH
HH
HL
Sharks
LL
(Fific & Townsend, 2010)
Participant 04
720
RT (ms)
HH
10
740
Conjunctive-rule
classification “AND”
0.3
Sharks 0.0
0
A catalog of mental architectures
Eye- separation
8
760
650
600
A
Jets
6
Converging evidence
200
700
0.004
0.004
Sharks
LH
H
4
Errors
RT(ms)
0.2
0
200.
200. 400.
400. 600.
600. 800.
800. 1000.
1000. 1200.
1200. 1400.
1400.
LH
HL
2
Block (2 x Session)
Proportion of errors
HH
Target
LH
HH Category
Sharks
150
550
Conjunctive-rule classification “AND””
Conjunctive-rule classification “AND”
HL
0
HH
Tutorial: how to calculate the survivor
interaction contrast (SIC) function
Experimental study
HH
HL
12
0.0
Target Category
LH
700
10
20
30
40
RT ms
50
60
A Catalog
HH
10
750
Tutorial
50
SIC(t) = Sll(t) - Slh(t)- (Shl(t) - Shh(t))
500
600
1
Survivor interaction contrast (SIC):
8
Session 17-18
0.2
150
6
800
0.4
100
RT ms
4
100
RT ms
850
0.4
0.1
400
Participant 03
0
0.4
0
2
600
Block (2 x Session)
Reaction time Survivor functions
The main SFT statistic
0.1
0.0
0
Session 15-16
Session 13-14
50
200
560
0
0.2
0
150
Session 11-12
580
0.4
50
100
RT ms
620
0.4
0
640 50
0
200
Lips- position
50
660
Proportion of errors
0.4
0.2
Proportion of errors
0.4
700
Proportion of errors
0.4
0.2
680
RT (ms)
0.2
700
0.3
800
RT (ms)
0.2
Session 7-8
SIC
720
0
0.2
0
0.3
Proportion of errors
0
900
740
0.2
SIC
SIC
SIC
0
Parallel, or coactive architecture
Mandatory exhaustive stopping rule
Super-capacity
Interdependencies between feature
detectors
Lips- position
•
•
•
•
0.2
MeanParticipant
RT trend
02
760
0.4
RT (ms)
Defining holism/configurality in
terms of processing characteristics:
Systems factorial technology (SFT)
0.4
0.2
SIC
We analyzed the underlying fundamental processes engaged in
forming holistic perceptual representations. The subjects
participated in a face categorization task over multiple
sessions. We applied the systems factorial technology (SFT) to
analyze the properties of the observed response time (RT)
distributions. The key statistic was a survivor interaction
contrast function (SIC). Over the course of extensive practice,
the observed SICs exhibited a specific pattern of shape
transformations that could be described as a "snake wiggle".
The observed SIC signature indicated that the processing
mechanism behind holistic perception relies on strong positive
facilitation between feature detectors, within the parallel
mental network. The converging evidence is provided by the
additional qualitative RT test (Fific, Little & Nosofsky, 2010).
Session 5-6
780
RT (ms)
0.4
Participant 01
Proportion of errors
Session 1-2
RT (ms)
Introduction
Errors
RT(ms)
Signatures
70
 Let’s wiggle: The SIC function wiggles
its way to S-shaped positive function
 Robustness: All subjects wiggled
 Coactivation: The target signature is
Coactive, an indicator of strong holism
 Performance superiority: Mean RT
decreases, and accuracy improves
 Introspection: The verbal reports
 Contrast faces wiggled to coactivation,
too.
 The snake wiggle is a dynamic signature
of holistic perception
Recommended Readings
Fific, M., Little, D. R., & Nosofsky, R. M. (2010). Logical-rule models of classification response
times: A synthesis of mental-architecture, random-walk, and decision-bound approaches.
Psychological Review, 117, 309–348.
Fific, M., & Townsend, J. T. (2010). Information-processing alternatives to holistic perception:
Identifying the mechanisms of secondary-level holism within a categorization paradigm.
Journal of Experimental Psychology: Learning, Memory, and Cognition, 36, 1290-1313.
E-mail: fificm@gvsu.edu