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Cognitive control, hierarchy, & the rostro-caudal organization of the prefrontal cortex
David Badre
Department of Cognitive & Linguistic SciencesDepartment of Psychology
Brown University
What does neural systems level data tell us?
• Action hierarchy may not require a hierarchical system
• Complex actions can be represented hierarchically
Sandwich for lunch
Make sandwich Pack sandwich
Slicing bread Spreading Mayonnaise
Etc…
Action and the Frontal Lobes
• Frontal lobe dysfunctionInability to organize or plan a sequence of behaviors(Shallice and Burgess, 1991)
Vulnerability to action slips(Schwartz et al., 1998)
Rostro-Caudal Axis of the Frontal Cortex
• Perception-Action cycle (Fuster, 1997; 2001; 2004)
• Human Neuroimaging EvidenceRelational complexity(Christoff & Gabrieli, 2000; Christoff et al., 2003)
Temporal organization of behavior(Koechlin et al., 2003; Koechlin & Jubault, 2006;
Koechlin & Summerfield, 2007)
Fuster, 2004
Talk Outline
• FMRI evidence of hierarchy along rostro-caudal PFC
• Disruption of PFC hierarchy
• Learning at different levels of PFC hierarchy
Prefrontal Cortex and Cognitive Control
Cognitive control processes represent contextual information to bias relevant representations over competitors.
Hypothesis 1: Manipulate control by varying competition
Response 1 Response 2
Cue Cue
Response 1 Response 2
Cue 1 Cue 2
Response 2 Response 1
Cue 1 Cue 2
Hypothesis 2: Regional differences in PFC are determined by the level of abstraction of competing action representations.
Level 1: Competition among Responses
12 3
4
Badre and D’Esposito, JOCN, 2007
Level 1: Competition among Responses
1 Response(no competition)
1 1 22 Responses
3 Response Levels
1 2 3 44 Responses
Level 1: Competition among Responses
-.4
0
.4
.8
1 2 3 4 5 6 7 8 9 101112
4 Responses2 Responses1 Response
TR
PS
C
Badre and D’Esposito, JOCN, 2007
Level 2: Competition among Features
1
1 - Positive
22 - Negative
Features
Badre and D’Esposito, JOCN, 2007
3 Feature Levels
Level 2: Competition among Features
1 Feature 2 Features 4 Features
Level 2: Competition among Features
TR
-.1
0
.1
.2
1 2 3 4 5 6 7 8 9 101112
4 Features2 Features1 FeatureP
SC
Level 3: Competition among Dimensions
1
1 - Match along relevant dimension
22 - Mismatch along relevant dimension
DimensionsOrientation
TextureShapeSize
Badre and D’Esposito, JOCN, 2007
3 Dimension Levels
Level 3: Competition among Dimensions
1 DimensionOrientation Orientation Texture
2 Dimensions
ShapeOrientation
SizeTexture
4 Dimensions
Level 3: Competition among Dimensions
-.2
0
.2
.4
.6
1 2 3 4 5 6 7 8 9 101112
4 Dims2 Dims1 Dim
TR
PS
C
Badre and D’Esposito, JOCN, 2007
Level 4: Competition among “Contexts”
Size Texture Shape Orientation
Recent Instructions
3 Context Levels
100% mapping 50% mapping 25% mapping
Badre and D’Esposito, JOCN, 2007
Level 4: Competition among “Contexts”
0
.04
.08
0 .5 .25Mapping Frequency
Sus
tain
edA
dj iP
SC
Interim Conclusions
• FMRI evidence of hierarchy along rostro-caudal PFC
• Disruption of PFC hierarchy
– Hierarchical system in PFC engaged by competition in action system– Hierarchy ranked by level of abstraction of representations