Neural Basis of Social Cognition: Mirror Neurons & Emotional Understanding

1. A Unifying View of the Basis of Social Cognitionby: Vittorio Gallese, Christian Keysers, and Giacomo Rizzolatti Amanda Issa Angela Arreola Stacy Struhs

2. Focus of the Paper Provide a unifying neural hypothesis on how individuals understand the actions and emotions of others Claims: Fundamental mechanism at the basis of the experiential understanding of others� is the activation of the MIRROR NEURON SYSTEM

3. Humans Survival and success depends on ability to thrive in complex social situations Our ability to understand the feelings and/or actions of others Derived from neural mechanisms that allow us to experientially comprehend actions and emotions of others as well as mimic them Conceptual reasoning is NOT the fundamental mechanism in understanding others Understanding ACTION and EMOTION

4. Observer and the Observed The observer and the observed are the SAME! Why? Because both are endowed with the same brain-body system What does this mean? The brain has the ability to relate the first and third person experiences Example: Connecting �I do and I feel� to �He does and he feels�

5. Action and Emotion Action Neural system responds both when we execute a particular directed action AND when we observe someone else performing a similar action Emotion Similar mechanism to action understanding that bridges the first and third person experiences

6. The Neural Mechanism Action Understanding Producing meaning for the visual representation MIRROR NEURONS! Found in the ventral premotor cortex (area F5) of macaque monkeys Same population of neurons responds when monkey performs specific goal directed action and when it observes another performing that same action The action is understood because the observer knows the outcome of the action

7. Evidence Evidence for motor involvement in action understanding Experiment: Evaluate the activity of F5 mirror neurons while monkeys understand the meaning of the action, without access to the visual features that trigger mirror neurons (MN).

8. First Study MN tested in two conditions 1: Monkey could see ENTIRE action 2: Same action but hand/object interaction blocked by screen

9. Data Condition One Condition Two

10. Data

11. Second Study F5 MN recorded when monkeys saw and heard executed noisy actions, only saw, or only heard.

12. Results 15% of MN are responsive to presentation of actions accompanied by sounds also responded to the presentation of the sound alone! Thus, �audiovisual MN� represent actions independently of whether these actions are performed, heard or seen. Convincing?

13. Compared to Human Data Observation of actions performed by others activates cortical motor representations MN system formed by cortical network make up Rostral part of inferior parietal lobule Caudal sector of inferior frontal gyrus Adjacent part of pre-motor cortex

14. Human MN System Responds to wider range of actions Presence of object appears to be necessary to MN activation in monkeys, but mimed actions suffice to cause firing in human system Motor evoked potentials are faciliated when individual observes meaningless hand gestures as well as when a transitive action is observed

15. Summary Thus Far Concurrent activation of similar parts of the motor system when we perform and when we observe a particular action Actions are understood by having the ability to mimic them and know the purpose of the action

16. Emotion Understanding Mirror neurons as the mechanism by which we understand the actions of others Are others� emotions understood the same way? Yes, via neurons in the insula Disgust

17. Monkey Data Monkey insula divided into two main subdivisions Anterior (visceral) Sector Multimodal Posterior Sector Anterior Sector receives input from: Olfactory and Gustatory centers Anterior sectors of ventral bank of superior temporal sulcus Where there are neurons that respond to faces

18. Monkey Data In addition, insula receives interoceptive afferents Stimulation causes viscero-motor responses

19. Human Data Anterior insula activated by disgusting olfactory and gustatory stimuli, as in monkeys Also activated by disgusted facial expressions Elicits viscero-motor responses

20. Insular Lesions Patient NK, �disgust deafness,� left insular lesion Lack of response to visual and auditory stimulation Reduced experiential sensation Almost two standard deviations below normal Patient B, bilateral lesion Deficits in recognition of disgusted facial expressions Ingests food indiscriminately, even inedible items

21. fMRI Data Disgusting Odorants and Movie Clips Wicker et al, 2003

22. Neural structures associated with Disgust Areas involved in experience and the perception of disgust. Insula Fundamental motor structures involved in emotion expression and action control Anterior Cingulate Cortex (ACC) Basal Ganglia

23. Structures involved in the empathy of pain Used FMRI to show that these structures also mediate empathy for pain Anterior Insula ACC

24. Towards a unifying neural hypothesis of the basis of social cognition A bridge between ourselves and others The understanding of basic aspects of social cognition depends on activation of neural structures normally involved in our own personally experienced actions or emotions. Network of activation: Parietal and Premotor areas The �As If � Theory� Do we just see or hear an action or emotion? No, they postulated that side by side with the sensory descriptions of the observed social stimuli, internal representations of the state associated with these actions or emotions are evoked in the observer �as if� they were performing a similar action or experiencing a similar emotion.

25. The Mirror Mechanism or �As if� Theory According to their view: What is crucial for both the first and third person comprehension of social behavior is the activation of the cortical motor or visero-motor centers, the outcome of which, when activating downstream centers, determines a specific �behavior�, be it an action or an emotional state. Further experiments�(Box 3) In favor of this theory, studies found that actions belonging to the motor area of the observer (biting) are mapped on the observer�s motor system Likewise, actions that do not belong to this area (barking) are mapped out on the basis of their visual properties.

26. The Mirror Mechanism Social cognition is not only thinking about the contents of someone else's mind� Our brains have developed a basic functional mechanism ( mirror mechanism) which gives us experiential insight into other minds. This mechanism provides the first unifying perspective of the neural basis of social cognition.

27. Problems with other theories of understanding emotion Damasio and coworkers: �The feeling of emotions depends on the activation of the somatosensory cortices in the broader sense, and of the insula in particular.� Differs from the �as if� theory presented by authors, in regards to the underlying neuromechanism. Authors indicate motor and viscero-motor centers as central areas involved, not just the somatosensory area.

28. Discussion Questions Is the mirror system for actions and for emotions, functioning normally in people with autism, whose understanding of other minds is impaired? No, they have observed abnormalities in the MNS system as well as abnormalities in other areas in the brain. Baby�s first steps http://www.youtube.com/watch?v=ua3P81gjdKg