 Empathy: enables sharing of emotion, pain, and sensation of others.  Perception-action model of empathy › Observing or imagining another person in a particular emotional state activates a representation of that state in the observer. › Common activation for experiencing a feeling (i.e. pain) and perceiving the same feeling in someone else.  Empathy for Pain shows activation in: › Anterior Insula (AI) and Fronto-insular Cortex (FI) › Anterior Cingulate Cortex (ACC)

 Hypothesis 1 : Pain-related empathic responses in A1/F1 and ACC will be elicited when observing a fair person in pain, but will be reduced or absent when observing an unfair person in pain.  Hypothesis 2: Increase in activation in brain areas known to be important in reward processing due to satisfaction from punishing unfair players. › Ventral Striatum, Nucleus Accumbens, and Orbito-Frontal Cortex

 Subjects: 16 men and 16 women  Scanner: 1.5 T Siemens Sonata MRI scanner  Economic game model: Prisoner’s Dilemma game - used to induce liking or disliking of actors by subjects. Male/female subjects rated fair players significantly more fair, agreeable, likeable, and attractive.

 Subject plays PDG – induce liking/disliking  Pain administered by stimulation through electrodes to the dorsum of the right hand of all three participants  fMRI -measure brain responses when individuals empathized with pain of someone they liked or disliked.  Rate: stimulation intensity, liking of both actors, and desire for revenge.

 Self-felt pain: increase in A1 and ACC activity.  Unfamiliar, but likeable person in pain: significant activation in A1 extending into F1 (both genders) and ACC (women )

 Unfair vs. fair player in pain Women: no significant difference in empathy- related pain activation Significant activation in bilateral A1/F1 and ACC in all three conditions Men: significant increase in F1 activation for fair player and no increase in F1 activation for unfair players.

 Reward processing areas (ventral striatum, nucleus accumbens, and left orbito-frontal cortex) show increase activity in men only.  Men express stronger desire for revenge › Greater activation in nucleus accumbens

 Selfish (unfair) behavior abolishes empathic responses in the brain.  People (men) value gains of others positively only if they are perceived to act fairly.  Humans derive satisfaction from seeing ‘justice’ administered, even if punishment is out of their control.

Strengths  fMRI scanner  Color-coded fMRI images for men/women Limitations  Experimental design favored men – punishment related to physical threat.  Conduct experiment with punishment more relevant to women – ex: psychological threat.