Emotion and Stress Notes

Emotion & Stress

• PYB304 Behavioural Neuroscience, Ottmar Lipp

• Topics:

  • What is an Emotion

  • Approaches to emotion

  • Discrete (basic) emotions

  • Emotions as emerging constructs

  • Research on emotion: facial expression processing; fear & anxiety

  • Stress and immunology

A brief history of Emotion in psychology

• Central topic early on (Wundt, James)

  • Introspection

  • Behaviourism

  • Cognitive revolution

  • Computer metaphor

  • Emotional Renaissance

Background Renaissance of emotion research in Psychology

• Starting around 1990

  • Journals: Emotion; Emotion Review; Cognitive, Affective & Behavioural Neuroscience

  • Affective Neuroscience

  • Experimental Psychopathology (NIMH RDoC)

Clarifying some terms: What is an Emotion?

• Attempt at a summary:

  • Strong reactions of most/all bodily systems

  • Triggered by (our interpretation of) events

  • Can disrupt on-going activity

  • Adaptive

  • Communicate information about feeling states

  • Affect survival of individual and species

  • Based on genetic processes that affect working of the brain

Clarifying some terms

• Affect:

  • More general; hedonic tone of an emotional state (positive/negative dichotomy)

• Mood:

  • Prevailing state that lasts longer than emotional state - less intense

• Feeling:

  • Subjective experience that accompanies an emotion

Approaches to emotion: James-Lange theory

• Activating Event -> Physiological Reaction -> Emotional Response

  • A dog barking -> Increased heart rate; sweating; quickness of breath -> Fear/Anxiety

Approaches to emotion: Traditional view (Russell)

• Event (e.g., danger) -> Emotion -> Subjective Feeling (e.g., afraid), Nonverbal Signal (e.g., face, voice), Autonomic Pattern, Instrumental Action (e.g., flight)

• Emotion mediates between an antecedent and its various manifestations.

Approaches to emotion: Basic emotions

• Basic:

  • Distinct from others

  • Evolved because they are adaptive

How many basic emotions?

• Sources:

  • Introspection (Wundt)

  • Judgement of facial expressions

  • Analyses of language

How many basic emotions?

• Depends: 5 to 15

  • 5: fear, anger, sadness, happiness, love

  • 15: amusement, anger, contempt, contentment, disgust, embarrassment, excitement, fear, guilt, pride in achievement, relief, sadness/distress, satisfaction, sensory pleasure, shame

  • Most frequently used: fear, anger, sadness, happiness, disgust, surprise (Ekman, 1999)

Criteria for basic emotions (Ekman, 1999)

• Distinctive universal signals

• Specific physiology

• Automatic appraisal mechanism

• Universal antecedent events

• Distinctive appearance during development

• Observable in other primates

• Fast onset

• Short duration

• Onset is not controllable

• Associated with distinct subjective experiences

Approaches to emotion: Emotions as emergent constructs

• Problems of basic emotion approach:

  • No agreement on number

  • Difficult to meet criteria

  • Searching for basic emotions in the brain

Approaches to emotion: Emotions as emergent constructs (Lindquist et al., 2012)

• Locationist Hypotheses of Brain-Emotion Correspondence:

  • Fear: amygdala

  • Disgust: insula

  • Anger: OFC (orbitofrontal cortex)

  • Sadness: ACC (anterior cingulate cortex)

• Meta-analytic findings of emotion brain areas with a consistent increase in activity across studies of emotion:

  • Default network (medial prefrontal cortex, medial temporal cortex, ventrolateral prefrontal cortex)

  • Salience network (insular cortex, anterior cingulate cortex, amygdala)

  • Frontoparietal network (ventrolateral prefrontal cortex)

Approaches to emotion: Emotions as emergent constructs (Russel, 2003)

• Core Affect

• Perception of Affective Quality

• Attribution to Object

• Appraisal

• Prototype of a Specific Emotion

• Action

• Emotional Meta-Experience

• Emotion Regulation

• An observer notes a resemblance between a pattern of components and a cognitive prototype for an emotion.

Emotion: Intermediate summary

• Rediscovered after cognitive revolution stalled

• Area of vivid theoretical debate

• Active area of experimental research

  • Examples:

    • Facial expression processing

    • Fear and anxiety

Facial expression processing

• Are some facial expressions processed preferentially?

• Visual search: Face in the crowd effect

  • Find angry faces faster among happy than vice versa (not true)

• Facial expression recognition: Happy face advantage

Happy face advantage

• Faster to recognize happy faces as happy than angry faces as angry (Leppänen & Hietanen, 2003)

• Sensitive to social category cues, person knowledge, contextual information

Facial expression processing: Intermediate summary

• Different paradigms may give different results

• In speeded recognition: Happy face advantage

• Sensitive to social category cues, person knowledge, contextual information…

• Do not fully understand underlying process

Fear and anxiety

• Fear

  • basic emotion

  • adaptive

• Prevalence of fear/anxiety related disorders: 7% of population in 2019 (self-report)

How to research fear?

• Of rodents and humans

• Fear evoking situations (unconditioned fear)

• Acquired fear (fear conditioning)

• Amygdala – gateway to fear (and other things)

• Lesions disrupt fear responses

Fear

• Emotional stimulus -> Sensory thalamus -> Sensory cortex -> Amygdala -> Various outputs (e.g., hypothalamus, brainstem) -> Behavioral, autonomic, and endocrine responses.

• Key structures in the fear circuit:

  • Amygdala (basolateral complex and central nucleus)

  • Hippocampus

  • Bed Nucleus of Stria Terminalis (BNST)

Tracing the fear circuit

• Example: Startle modulation

• Training: Light and shock paired

• Testing:

  • Noise-alone trials

  • Light-noise trials

• Normal startle (in dark)

• Potentiated startle (in light)

Picture viewing: Startle magnitude

• Startle response is greater for unpleasant pictures compared to neutral or pleasant pictures.

Picture viewing in psychopaths (Patrick et al., 1993)

• Psychopaths show reduced startle potentiation to unpleasant pictures.

• PCL-R Factor 1 (