Lec 6 Empathy

Lecture 6: Empathy

What is Empathy?

  • Definition: Empathy is defined as “the ability to appreciate the emotions and feelings of others with a minimal distinction between self and other” (Decety 2011, Emotion Review, 3:92-108).

  • Alternate Definition: Empathy is also described as “the ability to understand and vicariously experience the feelings of another person” (Stevens & Taber 2021, Neuropsychologia, 159:107925).

  • Sympathy Definition: Sympathy is characterized as “feelings of concern about the welfare of others” (Decety 2011, Emotion Review, 3:92-108).

Components of Empathy

  1. Affective Arousal
       - Discrimination of stimulus valence: distinguishes between appetitive or aversive, pleasant or unpleasant, threatening or nurturing emotional stimuli.

  2. Emotion Awareness and Understanding
       - This component overlaps with the Theory of Mind or Mentalizing aspects, allowing individuals to recognize and interpret emotional states not just within themselves, but also in others.

  3. Emotion Regulation
       - Refers to the ability to control one's emotions and manage drives and motivations in response to affective stimuli (Decety 2011, Emotion Review, 3:92-108).

Empathy Types

  • Emotional Contagion
       - Described as the automatic experience of another's emotional state without deliberate intention and without critically differentiating between self and other. It may serve as a precursor to affective empathy.

  • Emotional Mimicry
       - Involves matching the emotional display of another individual without actually experiencing the emotion oneself.

  • Affective Empathy
       - This refers to sharing in the emotional state of another, encapsulated in the phrase “I feel your pain.” It is sometimes called experience sharing and implies recognition that the source of the emotion is external, not internal.

  • Cognitive Empathy
       - Sometimes referred to as mentalizing or perspective-taking, this form of empathy involves understanding another’s experiences by adopting their perspective, without necessarily experiencing the same emotion—expressed as “I know you are experiencing pain.”

Neurobiology of Empathy

  • Perception-Action Model (Direct-Matching Hypothesis)
       - This model suggests that perceiving another’s emotional state automatically triggers the corresponding representation of that state in the observer. This activation leads to somatic and autonomic responses, thus generating a similar emotional state in the observer (Preston & de Waal 2002).

  • Shared Neural Circuits
       - Empathy activates the same neural circuits involved in the observer's own emotional experiences, indicating a strong biological underpinning.

Pain and Empathy

  • Pain as a Research Model
       - Pain is an ideal model for studying empathy because it signals others to provide help, leading to caring behaviors.
       - Studies show both self-inflicted pain and vicarious pain activate overlapping neural substrates.
       - Overlap in Neural Activation
         - Findings suggest that both self-pain and vicarious pain activate similar areas of the brain, specifically the dorsal anterior cingulate cortex (dACC), anterior insular cortex (AIC), and somatosensory cortex.
         - Notably, there is only partial overlap.
           - Self pain involves connectivity with midbrain and periaqueductal gray (PAG) linked to AIC.
           - Vicarious pain involves connectivity with the medial prefrontal cortex (mPFC) alongside the anterior cingulate cortex (ACC) and AIC, as well as connectivity with the superior temporal sulcus (STS), posterior cingulate, and precuneus connected to ACC.

Experimental Evidence

  • Morrison et al. (2004): This study involved adult males and females who either felt pin pricks on their fingertips or watched videos of others receiving pin pricks.
       - Controls felt innocuous touch or saw videos of innocuous touch.
       - Findings revealed that feeling and seeing pain activate some of the same brain areas, notably the Anterior Cingulate Cortex (ACC).

  • Affective Empathy Activation in the Brain
       - Studies have assessed brain area activation through fMRI during experiences of self pain and vicarious pain and identified two key areas consistently active:
         - Anterior/mid cingulate cortex (aMCC) during both self and vicarious pain.
         - Posterior insula (PI) for awareness of body states and anterior insular (AI) cortex for the evaluative component relating to perception of pain and emotion.

Cognitive Empathy Activation in the Brain

  • Cognitive empathy is linked to activation in the theory of mind/mentalizing network. Key areas activated include:
       - Dorsomedial Prefrontal Cortex (dmPFC)
       - Ventromedial Prefrontal Cortex (vmPFC)
       - Temporoparietal junction (TPJ)
       - Superior temporal sulcus (STS)
       - Temporal Pole (TP)

Oxytocin's Role

  • Oxytocin's Actions: The effects of oxytocin can depend on the perception of in-group versus out-group individuals. It may enhance the salience of social stimuli and can increase the ability to recognize emotions in facial expressions.
       - Social Salience Hypothesis: Proposes that oxytocin facilitates attention and orientation toward social stimuli, enabling better processing of positive and negative contextual cues.

Effects of Environment or Context on Empathy

  • The activation of empathy-related neural substrates is influenced by multiple factors:
     1. Situation
        - Example: Variations in empathy responses observed in contexts such as healthcare settings (e.g., nurse studies).

  1. Target Individual
       - Factors including trustworthiness, closeness (friend vs. stranger), social status, group membership (in-group/out-group), and overall familiarity affect empathetic responses and can be situation-dependent.

Evolutionary Origins of Empathy

  • Extended Parental Care: The ability to perceive and respond to hunger, pain, distress, and fear in offspring is fundamental for extended parental investment.

  • Kin Selection Hypothesis: Empathic helping, or sympathy, may have evolved from kin selection as proposed by Wilson (1988). This hypothesis suggests that empathy extends beyond kin selection and reproductive fitness.

  • Altruism Examples: Human examples of altruism such as sending aid to victims of natural disasters illustrate empathy that transcends immediate kin relationships.

Empathic Behavior in Animals

  • Empathically Motivated Prosocial Behavior: Studies show that rats will free a trapped cage mate significantly more often than for an empty restrainer or novel object, indicating empathetic behavior.
       - Referenced study: Ben-Amin Bartal et al. (2011) Science, 334:1427-1430.

  • Gender Differences: Female rats are more likely to engage in freeing behaviors compared to male rats.

  • Continued Behavior: Rats continue to free their cage mates even when social interaction is not possible following the act, indicating a motivation not solely based on social contact.

  • Motivation Levels: Rats show a willingness to free a restrained cage mate at a rate comparable to their motivation for obtaining chocolate, indicating a significant level of empathy.

  • Stranger Empathy: Rats have been observed to open restrainers for both familiar cagemates and strangers, but with the caveat of strain familiarity impacting success.

  • Cross-fostering: Research indicates that rats raised with a different strain will help other rats of that strain rather than their genetic strain, indicating that familiarity rather than genetic relatedness guides helping behavior.

Why Study Empathy in Animals?

  • Investigating empathy in animals can help scientists understand:
     1. The basic components that constitute empathy.
     2. To appreciate the cognitive abilities across species and assess whether human cognition is unique.
     3. The evolutionary development of empathy by examining neural circuitry.
     4. The potential for conducting experimental manipulations to acquire more direct evidence of empathetic behavior rather than relying solely on correlation from fMRI studies.
     5. The capacity to assess activation within individual neurological pathways rather than entire brain regions.

Social Transfer of Pain in Mice

  • Research indicated that bystander (BY) mice interacting with CFA-injected mice, which induce arthritic pain, exhibit hyperalgesia (increased pain sensitivity) similar to that experienced by CFA-injected mice, demonstrating emotion contagion (Smith et al. 2021, Science, 371:153-159).

  • Neural Substrate Activation: Interactions with CFA mice activate brain regions associated with empathy in humans including ACC and insula cortex while also engaging areas involved in pain transmission such as the thalamus and central amygdala.

  • Optogenetic Insights: Findings show that activation of the ACC is essential for social transfer of pain.
       - Inhibition Studies: Optogenetic inhibition of the ACC hinders social transfer of pain, underscoring the importance of this brain area in empathetic responses.
       - Pathway Regulation: The ACC-Nucleus Accumbens (NAc) pathway modulates social transfer of pain, suggesting that optogenetic manipulations can enhance or prevent the empathetic response depending on stimulation.