Emotions (revised) Flashcards
Amygdala and fear
- Patient S.M. had selective deficits to judge whether a fearful expression was displayed
- Patient S.M. had no problem rating any of the other emotional responses
- Patient S.M. also had selective deficits in generating an image of fearful expressions
- The amygdala is a small almond shaped brain nucleus, which is associated with fear
- Lesions to the amygdala in monkeys cause loss of innate fear, becoming hyperoral, hypersexual and docile
- Lesions in humans affect emotional fear processing (not exclusively)
How are emotions classified?
- Darwin claims there is a widespread universality on certain emotional expressions; Emotions are biological and innate to a certain extent
- A branch in social psychology argues that it is a learned & culturally developed form of social communication, and can differ in meaning between different cultures
- 6 basic emotions: happiness, sadness, anger, fear, surprise, disgust
What are the difficulties in emotion classification?
Discrepancies between the biological and social perspectives
Do you know different models relating to emotions?
- The Circumplex Model of Emotions:
- Arousal Levels - how they activate/deactivate a person
- whether they are pleasant/unpleasant - Circuit-Based Model
- Uses brain circuits involved in processing specific emotions - James-Lange Theory
- Argues that perception triggers bodily emotional responses, which then trigger the emotional perception
What are the key brain structures involved in the processing of emotions?
- Limbic System
- Hippocampus as the center piece of the limbic system
- People originally thought that the limbic system was mostly involved in emotional processing; Concept is not outdated
- Many areas that are linked to the limbic system perform functions different from emotional processing
How are emotions triggered?
It is still debated whether the feeling state of emotions is triggered by an awareness of automatic bodily changes (incl facial expressions) that have occurred, or emotion perceived first and then triggers the bodily changes
Arg 1: James-Lange Theory
- Bodily reactions -> Conscious perception of emotion
- You seeing and consciously perceiving the stimulus is what induces the bodily reaction
- Support 1:
*Damasio’s card game
*Somatic marker hypothesis: Bodily reactions trigger consciousness, and also help you avoid danger
Arg 2: Cannon-Bard Theory
- Something bodily first -> Triggers the emotional experience -> The realisation then combines for you to have a conscious experience (Conscious response)
- Support 1:
*Removed ‘all’ sympathetic visceral feedback in cats by brain/midbrain stem sectioning
*These cats still expressed emotions = Argument against feedback from visceral system as an emotion trigger
- Support 2:
*Russell was given adrenaline to reduce pain perception (causes change in heart rate, sweating, arousal, etc. which benchmark fear)
*Russell said he did not experience fear
What is fear conditioning?
- Associative learning where an individual learns to associate a neutral stimulus (ex. bell) with a fear-inducing stimulus (ex. shock)
- Repeated pairings elicit a fear response in the individual when met with the neutral stimulus (even when the fear-inducing stimulus isn’t present)
- Extinction: You can get rid of the effects if you repeatedly present the conditioned stimulus without the aversive stimulus
How are emotions measured?
- Using the Circumplex Model of Emotions, you can measure emotions by its arousal levels (how they activate/deactivate a person) and by whether its pleasant/unpleasant
- Skin Conductance
- Emotionally arousing (positive or negative) stimuli cause us to sweat more
- This changes the electrical conductivity of the skin, which can thus be measured
- Ex. lie-detector tests
What part of the brain is relevant to value estimation?
- Orbitofrontal Cortex (OFC)
*Active in Damasio’s card game (activated before subjects can express what’s going on; brain before speech processing system) - Amygdala
High and Low Road to the Amygdala to Accommodate Both James-Lange and Cannon-Bard Theories
- Cortical (slow/high) road entails high level processing of information, where most likely conscious awareness of (e.g.) danger triggers fear and associated responses
- Subcortical (low) road allows for fast processing of potential danger/benefit, and physical reactions can be triggered before awareness of an emotion
What is the difference between implicit and explicit learning?
Implicit learning is done through conditioning, while explicit learning is done through direct instruction/elaboration
Example: fear conditioning and instructed fear
What are the roles of the hippocampus and the amygdala in explicit and in implicit emotional learning?
- Explicit: Hippocampus mediates learning by awareness (declarative memory system)
- Implicit: Amygdala mediates conditioned autonomic responses
- Amygdala activation aids the retention of hippocampus-dependent memories (emotional events are much better remembered)
What are implicit attitudes?
- Thoughts, feelings, or actions toward sth that arise due to past experiences which an individual is either unaware of or cannot attribute to a specific experience
- Can be positive or negative
What is a key determinant in fear perception?
Eye whites; Always more eye whites visible in those expressing fear
How do implicit attitudes manifest in brain activation pattern?
- Example: IAT, where the right amygdala is more active for black vs white faces
- Dissociations can exist between implicit and explicit attitudes
- Implicit attitudes correlate with amygdala activation, even in the absence of explicit attitudes (e.g. racial bias/stereotyping)
