Transcript pineda_slides - UCSD Cognitive Science

Social Cognition and the Mirror
Neuron System of the Brain
Jaime A. Pineda, Ph.D.
Cognitive Neuroscience Laboratory
COGS1 class
Motivating Questions
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How do our brains perceive the
mental states of others despite
their inaccessibility?
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How do we understand the
actions, emotions and the
intentions of others?
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Rationally?
Intuitively?
How do we understand firstand third-person experiences?
Classic Explanation
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Theory-Theory
(argument from analogy; disembodied
knowledge; visual hypothesis)
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Involves striate, extrastriate,
inferotemporal lobe and
superior temporal sulcus,
among others
A Different Perspective
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Simulation Theory
(Direct-matching hypothesis; embodied
knowledge)
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Map visual information onto
motor representations of the
same action
Mirroring systems
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bridges between perception
and action that allow for
simulation
 Mirror neurons
 EEG Mu rhythms
A Different Perspective
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Simulation Theory
(Direct-matching hypothesis; embodied
knowledge)
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Map visual information onto
motor representations of the
same action
Mirroring systems
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bridges between perception and
action that allow for simulation
 Mirror neurons
 EEG Mu rhythms
The Mirror Neuron System
Iacoboni and Dapretto, Nature Reviews, 2006,7:942-951
Pineda, Beh & Brain Functions, 2008, 4, 47
Biological Motion
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Visual system's ability to
recover object information
from sparse input
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Gender
Activity engaged in
Emotional state
Biological Motion Perception: Monkeys
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Perret and colleagues
(1989; 1990; 1994)
Cells in superior
temporal polysensory
area (STPa) of the
macaque temporal
cortex appear sensitive
to biological motion
Oram & Perrett, J. Cog. Neurosci., 1994, 6(2), 99-116
Biological Motion Perception: Humans
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An area in the superior
temporal sulcus (STS) in
humans responds to
biological motion
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Other areas do as well,
including frontal cortex,
SMA, insula, thalamus,
amygdala
Grossman et al. J. Cog. Neurosci., 2000, 12(5), 711-720
Brain Circuit for Social Perception (SP)
• SP is processing of
information that results in
the accurate analysis of
the intentions of others
• STS involved in the
processing of a variety of
social signals
Allison et al., Trends in Cog. Sci., 2000, 4, 267-272
Mirror Neurons
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A specific class of neurons that discharge
both when the monkey performs an action
and when it observes a similar action done
by another monkey or an experimenter
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Found in:
 area F5 (homolog of Broca’s area);
10-20%
 inferior parietal cortex (PF/7b)
Activated by:
 Goal directed actions (reaching,
grasping, holding)
 Observation of similar actions
performed by “biological” agents
Di Pellegrino et al., Exp. Brain Res., 1992, 91, 176-80
Mirror Neuron Activity
Rizzolatti et al., Cogn. Brain Res., 1996, 3:131-141
Perception-to-Action Mapping Selectivity
Congruent
(effector dependent)
Perception
Action
Logically-Related
(effector independent; 2X)
Understanding Intentions
Grasping
Umilta et al. Neuron, 2001, 32: 91-101
Mimicking
Mirror Neuron System
Sensorimotor
cortex
Inferior parietal
lobule
Inferior frontal
gyrus
Superior temporal
sulcus
Functional Significance
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Response facilitation
Mimicry
Simulation
Imitation learning
Understanding actions
Understanding intentions
Empathy
Theory of Mind
Language
Characterizing the System
motivational significance?
intentionality?
biological realism?
anthropomorphism?
transitive/intransitive actions?
MNS activity
generalizability?
social relevance?
learning?
No MNS Activity
Mu Rhythm
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8-13 Hz oscillation over sensorimotor cortex
Normal Oscillation
Self Action
Observed Action
Frequency Analysis of Mu Rhythm
(8-13 Hz)
P
o
w
e
r
(10-14 Hz)
Frequency
Does Mu Suppression Reflect Mirror Activity?
Baseline
Move
Observe
Imagine
Pineda et al., IEEE Trans. Rehab. Engr., 2000, 8(2): 219-222
Action Observation and Social Interaction
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To what degree do mu rhythms, like mirror neurons,
reflect social interaction?
Oberman et al., Social Cognitive and Affective Neuroscience, 2007, 2, 62-66
Experimental Paradigm
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Measured mu power (2 min of EEG) in normals (n=20)
ages 18-34 (mean=21.1, SD=3.40 ) under different
observation conditions:
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Non-interacting
Social Action - Spectator
Social Action - Interactive
Visual white noise
Engaged in continuous performance task during
observation
Non-interacting
Social Action - Spectator
Social Action - Interactive
Results
Degree of Social Interaction
4
3.5
3
2.5
2
1.5
1
0.5
0
Non-Interacting
Social Action,
Spectator
Social Action,
Interactive
Results
0.1
C3
CZ
0
-0.1
-0.2
-0.3
Social Action, Interactive
Social Action, Spectator
-0.4
Non-Interacting
C4
Autism Spectrum Disorder (ASD)
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Problems in the following domains:
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Social ability
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Language development
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Behavior
Common Characteristics
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Impairment in social play and imagination
Impaired ability to initiate conversations with others
Repetitive behaviors
Impaired sustained attention
Trouble Imitating others
Difficulty interpreting actions and intentions of others
Absence of empathy
Autism: A Dysfunctional Mirror System?
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No common underlying
mechanism has been
identified
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Deficits in imitation learning –
Rogers and Pennington, 1991
Deficits in mirror neuron system
- Williams et al., 2001
Hypothesis
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If mu rhythms reflect MNS activity and the capacity to
understand actions as well as learn through imitation,
then autistics should show differences in mu rhythms
compared to controls
Oberman et al., Cog. Brain Res. 2005, 24: 190-198
Experimental Paradigm
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Measured mu power (2 min of
EEG) in normals (n=12) and
autistics (n=10) under different
conditions:
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Self-movement of hand
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Watching video of someone
moving their hand
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Watching a video of a ball
moving up and down
Oberman et al., Brain Res Cogn Brain Res. 2005, 24(2):190-8.
Results
Results
Oberman et al., Neuropsychologia, 2008 Jan 19 [Epub ahead of print]
Creating a Temporary “Autistic” Brain
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Do sensorimotor mu rhythms reflect downstream
modulation from cells in premotor cortex?
RATIONALE
If mirror neurons in IFG are involved in the direct
modulation of mu rhythms, then temporary inhibition
of these neurons should prevent suppression of mu
rhythms and cause “autistic-like” behaviors.
Method
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Measured EEG mu power in typically developing
adults (n=8) under different conditions before and
after IFG stimulation
 Observation of movement (4 videos)
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Baron-Cohen’s Eyes Task
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Simple (hand movements) and complex (social
interactions)
Emotion and gender discrimination
1 Hz rTMS (5 min at ~ 40-50% MEP threshold)
targeted at left IFG
Eyes Task
Results
Reaction Time
Accuracy
Results
IFG STIMULATION
0.1
0.08
MU SUPPRESSION
0.06
0.04
0.02
0
-0.02
-0.04
PRE
-0.06
POST
-0.08
-0.1
C3
C4
C3
SIMPLE
C4
COMPLEX
MOVEMENT TYPE
Plasticity Induced Rehabilitation Training
Frontoparietal areas in an ASD
brain may be underconnected
SM
Cortex
If we change the dynamics of the
sensorimotor mu oscillations,
And these oscillations are
functionally linked to the MNS
network (IFG, IPL, STS),
Then we may change functional
connectivity and recover MNS
engagement,
Leading to positive changes.
IPL
IFG
STS
Reversing Social Deficits in Autism?
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Training
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30 min x 3/week x 10 weeks
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HF ASD: 7-17 yr olds; n=20
Experimental/Control groups
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Mu activity above threshold (E)
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EMG activity below threshold
(E/C)
Pineda et al., Research in ASD, 2008
Pre/Post Assessments
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Verification of diagnosis (IQ, ADI,
ADOS)
Quantitative EEG (QEEG)
Test of Variable Attention (TOVA)
Imitation ability (Apraxia imitation test)
Mu suppression index (MSI)
Autism Treatment Evaluation
Checklist (ATEC)
Neuroimaging (fMRI, fcMRI)
Pre/Post Assessments
Facial Emotions (n-back)
Physical Causation - ToM
Eyes Emotion Task - ToM
Mental Attribution- ToM
Behavioral Performance
400
ASD
(HITS/MIN)*THRESH
350
300
250
R2 = 0.7673
200
150
100
50
0
0
5
10
15
20
25
SESSIONS
400
TD
(HITS/MIN)*THRESH
350
R2 = 0.7068
300
250
200
150
100
50
0
0
2
4
6
8
10
SESSIONS
12
14
16
18
Mu Suppression Index
MU SUPPRESSION INDEX
LOG [CONDITION/BASELINE]
0.06
0.04
0.02
0
-0.02
-0.04
-0.06
CONTROLS
-0.08
EXPERIMENTALS
-0.1
HAND
SOCIAL
PRE-TRAINING
HAND
SOCIAL
POST-TRAINING
EEG Coherence
Sustained Attention
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Reduction trend in
ADHD score for
experimental group
Autism Treatment Evaluation Checklist
Future: Neuroimaging Techniques
structural
Diffusion Tensor Imaging
functional
Functional connectivity
A Fundamental Organizational Feature
of the Brain?
“Understanding others as intentional agents may be grounded
in the relational nature of our interactions with the world”
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Beyond understanding actions
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emotions: the root of empathy?
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sounds and other senses
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language
Other problems in “mirroring”
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Aberrant imitation learning: addiction?
What Is It Like To Be…?
Can aspects of subjective experience
be reduced to brain activity?
Thomas Nagel, The Philosophical Review 83 (1974).
Collaborators and Students
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Vilayanur
Ramachandran
Lindsay Oberman
Eric Altschuler
Andrey Vankov
Bill Skinner
Chulie Ulloa
Brendan Allison
Ed Hubbard
Joe McCleery
Erin Hecht
David Brang
Scott Carey
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Adrienne Moore
Rajiv Rao
Chris Robinson
Hanie Elfenbein
Alex Bressler
Steven Thurman
Jena Davis
Dong Suk
Christa Futagaki
Judith Kaye
Lee Edwards
Ralph-Axel Mueller
Brandon Keehn
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Oriana Clark
Jia-Min Bai
Derrick Asher
Dane Chambers
Matt Earhardt
Heather Pelton
Alicia Trigerio
Albert Ayala
Stephen Johnson
Steve Gilmore
Nick Pojman
Kelly Head