Upload
gisela-lancaster
View
36
Download
1
Tags:
Embed Size (px)
DESCRIPTION
Dean Mobbs PhD MRC-Cognition and Brain Sciences Unit. Social Neuroscience Approach to Social Cognition May 22-25, 2008 Ghent. Overview The Social Brain – Two Core Areas?. TP, Context and Faces Perception TP anatomy TP in Social Cognition and ToM Working Model of the Social Brain - PowerPoint PPT Presentation
Citation preview
Dean Mobbs PhD Dean Mobbs PhD
MRC-Cognition and Brain Sciences UnitMRC-Cognition and Brain Sciences Unit
Social Neuroscience Approach to Social Social Neuroscience Approach to Social CognitionCognition
May 22-25, 2008May 22-25, 2008
GhentGhent
Overview
•The Social Brain – Two Core Areas?.
•TP, Context and Faces Perception
•TP anatomy
•TP in Social Cognition and ToM
•Working Model of the Social Brain
•Some Future Directions
•Conclusions
Neural Systems in Social Cognition
Core Areas:
•Medial prefrontal cortex (mPFC) = interpersonal norms and scripts. ToM.
•Temporo-parietal junction (TPJ) = Goals intentions and desires of others (?).
What about the temporal pole!!
•Right Temporal Pole (TP) = Special role in ToM, social schemas and concepts??
- drop-out, ROI “hypothesis driven” approach and lack of tasks/theory about the TP .
Van Overwalle, 2008
• Soviet filmmaker Lev Kuleshov demonstrated that the manipulation of context can alter an audiences’ perceptions of an actor’s facial expressions, thoughts and feelings.
• Juxtaposing identical archived clips of actor Ivan Mozzhukhin’s face with either a scene of a funeral or a child playing led the audience to infer Mozzhukhin’s emotional disposition as subtly melancholic or elative, respectively
Context in Social Judgements: The Kuleshov Effect
Empirical studies of the Kuleshov effect
• Although Kuleshov’s observations were of a anecdotal nature, subsequent research has supported impact of contextual framing by showing that an observer can be influenced to perceive.
• Neutral faces as happy or sad (Wallbott, 1988).
• Angry facial expressions as fearful (Carroll and Russell, 1996).
• Screams as joyful (Goldberg, 1951).
We adapted the “Kuleshov Effect” paradigm to elucidate the neurobiological basis of contextual influences on emotional attributions
Methods
• Volunteers were explicitly rated emotional expression and mental-state (i.e. what the actor is thinking and feeling) from identical faces juxtaposed with negative, neutral and positively-valanced contexts
Mobbs et al. SCAN 2006
0
10
20
30
40
50
60
70
80
90
100M
orph
s
100% Happy
100% Fear
Top-down
Bottom-up
Bottom-up
• Context is most effective when a facial expression is source clarity of the face is low and source clarity of the context is high*, we also used neutral faces and faces displaying subtly fearful and happy facial expressions
*Ekman, Friesen and Ellsworth, (1982)
Ambiguous
Methods…
Pseudo-candid photo manipulation
• To emphasize a link between the actors’ faces and the contextual movie and reduce demand characteristics we used a pseudo-candid photo manipulation with subjects being led to believe that the actors’ expressions were in response to viewing a juxtaposed movie
*Ekman, Friesen and Ellsworth, (1982)
Task Example
Mobbs et al. SCAN 2006
Short Movie Response Rate
Results: Main Effects
Mobbs et al. SCAN 2006
Results: Simple Interactions
Mobbs et al. SCAN 2006
fMRI Results: Parametric Analysis
Regions associated with increased +
attribution
Regions associated with increased -
attribution
O’Doherty et al. NN (2001)
Mobbs et al. SCAN 2006
• Contextual framing is likely to rely on activation of stored knowledge derived from real-world experiences.
• It has been theorized that the right temporal pole serves as a repository for contextual schema or frames.
• Involved in storage of contextual information, particularly when of emotional significance.
• Connections with the distinct regions of the PFC may result in retrieval of contextual and episodic information (Badre et al 2005; Dobbins et al 2002).
Conclusion
Temporal Pole
•Right TP - binds together diverse aspects of nonverbal social-emotional communication (prosody, gesture, facial expression, autonomic responses to social stimuli, social context, etc) that must be linked for us to detect sarcasm, irritation, sadness, etc. in others.
•Left TP binds processing streams related to word and object meaning (shape, colour, size, texture, and stored word representations must be linked for us to recognize and name - William Seeley – personal communication).
Temporal Pole and Ventral-Stream
FFASTS
Ventral Stream
Identity – structural components of the Face
Top-down retrieval of social and emotional
information
Temporal Pole Connectivity
Olson, Plozker and Ezzyat, 2007
mPFC
Obfc
FFASTS
Hypothalamus
Left Temporal Pole in Face Processing?
Rothstein et al Nature Neuroscience, 2005
Impaired familiarity with preserved recollection after anterior temporal-lobe resection that spares the hippocampus (Bowles et al. 2007)
Right Temporal Pole in Face Processing?
Calder et al, Current Biology, 2007
Studies on primates have shown the TP to contain faces and eye direction responsive cells
Kriegeskorte et al, PNAS, 2007
Role for the Temporal Pole in Social Cognition?
• Social attributions are likely to rely on activation of stored contextual schemata derived from experience (Levanthal and Scherer, 1987; Bar, 2004).
• Acquired lesions in the vicinity of the right TP can result in the loss of recognition of famous scenes, loss of memory for events and loss of person related knowledge (Tranel et al., 1997; Kitchener et al., 1999; Gorno-Tempini et al., 2004).
• Patients with right, but not left, TP atrophy due to the tv-FTD exhibit changes in personality and socially appropriate behaviour (Thompson et al., 2003).
• Where are social/cultural conventions stored?
Temporal Pole in Social Conceptualization
Zahn et al. PNAS 2007
Social Concepts (honor–brave) minus
animal concepts (nutritious–useful)
Positive (honour–brave) – negative (tactless–impolite) social concepts
TP rCBF change associated with the perception of ToM animations vs Random animations (Castelli et al 2000)
Olson, Plozker and Ezzyat, 2007
Temporal Pole and ToM
Simulation Theory?
• What would I do or expect someone to do in that situation?
• Another interpretation is that the TP has some role in encoding personal memories• (Nakamura and Kubota, 1995).
• Theory of mind tasks = TP utilizes personal memories to comprehend the state of mind of others (Moriguchi et al., 2006).
• Strongest correlation with appropriateness was the TP
Evidence of anterior temporal atrophy in college-level soccer players. (Adams et al. Clin J Sport Med. 2007)
http://www.zidaneheadbut.co.uk/
ToM Social Schemas
Appropriate/expected social behaviour
Right Temporal Pole
Social Concepts
People Knowledge
Emotional episodic memory
Social attention
Congruency
Low-level Perception of
Socially Relevant Information and Attention
STS= biological motion,
Social attention, eye direction,
intentions
R TPJ=
Goals intentions and desires of others, ToM
mPFC = interpersonal norms and
scripts. ToM
High-level Perception of
Social Information
R TP = Socioemotional scripts. ToM
Working Model of Social Cognition
Low High
Low level social signals
(e.g. FFA =faces,
EBA Bodies etc
L TP = Familiarity – History Scripts (in group/out group)
Stored knowledge/cache
Low-level Perception of
Socially Relevant Information and Attention
STS= biological motion,
Social attention, eye direction,
intentions
R TPJ=
Goals intentions and desires of others, ToM
mPFC = interpersonal norms and
scripts. ToM
High-level Perception of
Social Information
R TP = Socioemotional scripts. ToM
Working Model of Social Cognition
Low High
Low level social signals
(e.g. FFA =faces,
EBA Bodies etc
L TP = Familiarity – History Scripts (in group/out group)
Stored knowledge/cache
Future Research
• Dissociate regions using fMRI and lesion studies
• Temporal order using MEG
• Alternative approach to functional localizers and ROI focused studies
• Developmental studies of social cognition
• Novel methods to evoke ecologically-valid studies of social cognition
• Form a more elaborate model of the social brain
Acknowledgements
Chris Frith Ray Dolan
Andy Calder
And colleagues at the FIL and CBU Social and Affective
Neuroscience Group
Tim Dalgleish Bill Seeley
Questions?