Social Cognition and the Mirror Neuron System of the Brain

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Motivating Questions Social Cognition and the Mirror Neuron System of the Brain Jaime A. Pineda, Ph.D.

inaccessibility? How do we understand the actions, emotions and the intentions of others? Rationally? Intuitively?

Classic Explanation A Different Perspective Theory-Theory (argument from analogy; disembodied knowledge; visual

Theory (Direct-matching hypothesis; embodied knowledge) Map visual information onto motor representations of the same

Different Perspective The Mirror Neuron System Simulation action Mirroring systems bridges between perception and

1 Motivating Questions Social Cognition and the Mirror Neuron System of the Brain Jaime A. Pineda, Ph.D. Cognitive Neuroscience Laboratory COGS1 class How do our brains perceive the mental states of others despite their inaccessibility? How do we understand the actions, emotions and the intentions of others? Rationally? Intuitively? How do we understand firstand third-person experiences? Classic Explanation A Different Perspective Theory-Theory (argument from analogy; disembodied knowledge; visual hypothesis) Involves striate, extrastriate, inferotemporal lobe and superior temporal sulcus, among others Simulation Theory (Direct-matching hypothesis; embodied knowledge) Map visual information onto motor representations of the same action Mirroring systems bridges between perception and action that allow for simulation Mirror neurons EEG Mu rhythms A Different Perspective The Mirror Neuron System Simulation Theory (Direct-matching hypothesis; embodied knowledge) Map visual information onto motor representations of the same action Mirroring systems bridges between perception and action that allow for simulation Mirror neurons EEG Mu rhythms Iacoboni and Dapretto, Nature Reviews, 2006,7:

Biological Motion Biological Motion Perception: Monkeys Visual system's ability to recover object information from sparse input Gender

temporal cortex appear sensitive to biological motion Oram & Perrett, J. Cog. Neurosci.

(STS) in humans responds to biological motion Other areas do as well, including frontal cortex, SMA, insula, thalamus, amygdala SP is

social signals Grossman et al. J. Cog. Neurosci., 2000, 12(5), 711-720 Allison et al., Trends in Cog. Sci.

and when it observes a similar action done by another monkey or an experimenter Found in: area F5 (homolog of Broca s area); 10-20% inferior

2 Biological Motion Biological Motion Perception: Monkeys Visual system's ability to recover object information from sparse input Gender Activity engaged in Emotional state 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), Biological Motion Perception: Humans Brain Circuit for Social Perception (SP) An area in the superior temporal sulcus (STS) in humans responds to biological motion Other areas do as well, including frontal cortex, SMA, insula, thalamus, amygdala 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 Grossman et al. J. Cog. Neurosci., 2000, 12(5), Allison et al., Trends in Cog. Sci., 2000, 4, Mirror Neurons Mirror Neuron Activity 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 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, Rizzolatti et al., Cogn. Brain Res., 1996, 3:

Perception-to-Action Mapping Selectivity

Characterizing the System Response facilitation

Understanding actions Understanding intentions

motivational significance? biological realism?

3 Perception-to-Action Mapping Selectivity Understanding Intentions Congruent (effector dependent) Logically-Related (effector independent; 2X) Grasping Mimicking Perception Action Umilta et al. Neuron, 2001, 32: Functional Significance Characterizing the System Response facilitation Mimicry Simulation Imitation learning Understanding actions Understanding intentions Empathy Theory of Mind Language generalizability? motivational significance? biological realism? intentionality? anthropomorphism? social relevance? transitive/intransitive actions? MNS activity learning? No MNS Activity The Mirror Neuron System Mu Rhythm 8-13 Hz oscillation over sensorimotor cortex Normal Oscillation Self Action Observed Action Iacoboni and Dapretto, Nature Reviews, 2006,7:

Frequency Analysis of Mu Rhythm Does Mu Suppression Reflect Mirror Activity? (8-13 Hz) P o w e r (10-14 Hz) Baseline Move Observe Frequency Imagine Pineda et al., IEEE Trans. Rehab. Engr.

Experimental Paradigm Measured mu power (2 min of EEG) in normals (n=20) ages 18-34 (mean=21.1, SD=3.

4 Frequency Analysis of Mu Rhythm Does Mu Suppression Reflect Mirror Activity? (8-13 Hz) P o w e r (10-14 Hz) Baseline Move Observe Frequency Imagine Pineda et al., IEEE Trans. Rehab. Engr., 2000, 8(2): Action Observation and Social Interaction To what degree do mu rhythms, like mirror neurons, reflect social interaction? Experimental Paradigm Measured mu power (2 min of EEG) in normals (n=20) ages (mean=21.1, SD=3.40 ) under different observation conditions: Non-interacting Social Action - Spectator Social Action - Interactive Visual white noise Engaged in continuous performance task during observation Oberman et al., Social Cognitive and Affective Neuroscience, 2007, 2, Non-interacting Social Action - Spectator 4 Social Action - Interactive Degree of Social Interaction Non-Interacting Social Action, Spectator Social Action, Interactive 4

Autism Spectrum Disorder (ASD) 0.1 0 C3 CZ C4 Problems in the following domains: Social ability intelligence Language acquisition -0.1-0.2-0.3-0.

5 Autism Spectrum Disorder (ASD) C3 CZ C4 Problems in the following domains: Social ability intelligence Language acquisition Social Action, Interactive Social Action, Spectator Non-Interacting Common Characteristics Autism: A Dysfunctional Mirror System? 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 No common underlying mechanism has been identified Deficits in imitation learning Rogers and Pennington, 1991 Deficits in mirror neuron system - Williams et al., 2001 Hypothesis Experimental Paradigm 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 Measured mu power (2 min of EEG) in normals (n=12) and autistics (n=10) under different conditions: Self-movement of hand Watching video of someone moving their hand Oberman et al., Cog. Brain Res. 2005, 24: Watching a video of a ball moving up and down Oberman et al., Brain Res Cogn Brain Res. 2005, 24(2):

Oberman et al., Neuropsychologia, 2008 Jan 19 [Epub ahead of print] Creating a Temporary Autistic Brain Method Do sensorimotor mu rhythms reflect downstream modulation from cells in premotor cortex?

6 Oberman et al., Neuropsychologia, 2008 Jan 19 [Epub ahead of print] Creating a Temporary Autistic Brain Method 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. Measured EEG mu power in typically developing adults (n=8) under different conditions before and after IFG stimulation Observation of movement (4 videos) Simple (hand movements) and complex (social interactions) Baron-Cohen s Eyes Task Emotion and gender discrimination 1 Hz rtms (5 min at ~ 40-50% MEP threshold) targeted at left IFG Pineda et al., in prep 6

Mirror Neurons in Primates, Humans, and Implications for Neuropsychiatric Disorders

Mirror Neurons in Primates, Humans, and Implications for Neuropsychiatric Disorders Fiza Singh, M.D. H.S. Assistant Clinical Professor of Psychiatry UCSD School of Medicine VA San Diego Healthcare System