Week 7: Emotion Flashcards
What are emotions?
Valenced responses to external stimuli and/or internal representations that….
- Involve changes in multiple systems
- Are distinct from moods
- Can be learned responses
- Appraisal of stimuli in terms of current goals
What are the 3 components of emotion?
- A physiological reaction (typically unconscious, automatic process)
- A behavioural response (eg. fighting/fleeing)
- A feeling (conscious, subjective feeling)
What are the basic emotions?
Anger Fear Sadness Enjoyment Disgust Surprise
These are universal, innate and short-lasting
What about complex emotions?
These are longer lasting that complex emotions with no universal facial expressions.
eg. Parental love, jealousy
These can be socially or culturally learned
What is the evolutionary role of emotion?
Emotions evolve from behaviours that indicate what an animal is likely to do next (eg. baring teeth is likely to mean an animal is likely to attack)
Enhances communicative function
What is the role of the medial prefrontal lobes in emotion?
Can be seen through the case of phineas gage who had dramatic changes in personality.
Reconstructions shows damage to the medial prefrontal lobes
What is the James-Lange theory of emotion?
According to this theory, witnessing an external stimulus leads to a physiological response. Your emotional reaction depends on how you interpret those physical reactions.
What is a limitation of the james-lange theory?
People with impaired autonomic responses can still experience emotion - which if following that theory there would be no autonomic response to trigger emotion
What is the cannon-bard theory of emotion?
A stimulus triggers both autonomic/skeletal response and emotion in parallel
What is the appraisal theory of emotion?
Emotion is the result of the appraisal of risk/benefit
Perception of stimulus - cognitive appraisal of stimulus - emotion - response
What is the Singer-Schacter theory of emotion?
Blend of the james lange and appraisal theories of emotion
Perception of a stimulus - general physiological reaction - cognition - emotion
Explain the sham rage findings in cats
Decorticated (removed cortex) cats exhibit extreme and unfocussed aggressive responses = sham rage
What brain structure was found to be required for sham rage to occur in these decorticated cats? and what does this mean?
The hypothalamus
Needed for the expression of aggression
What does bilateral damage to the amygdala cause?
A rare neurological disorder - Kluver-Bucy syndrome
What are the major symptoms of kluver-bucy syndrome?
Lack of fear!!
Urge to put objects in mouth, memory loss, hypersexuality, emotional blunting
Explain the HPA axis
The amygdala: detects things that are dangerous in the environment
Prefrontal cortex: regulates the stress response by making things seem less scary
Hypothalamus: wakes up the pituitary gland
Pituitary: hormones from here tell the adrenal gland to release cortisol
Cortisol: travels through the blood and tells other body parts to react to stress
What if we just observe someone else’s emotions, do we get emotional?
Brain activity for imagined, experienced or observed emotion is very similar
What are the main points that have been found when studying emotion
- Brain activity associated with each human emotion is diffuse
- There is usually motor and sensory regional activity along with an emotional response
What is urbach-wiethe disease? (SM case study)
Deficits in identifying/reproducing fearful emotional expressions of others
Rare neurological disorder resulting in atrophy in amygdala
This is not a conceptual fear - could describe situations in which would elicit fear and said she hated snakes and spiders but would not elicit any fear if she saw them
When rating facial expressions - rated as less intense
What do damages to the amygdala mean for fear conditioning
Lesions to amygdala block fear conditioning but not the unconditioned response to an aversive stimulus
What is the low road and high road with the amygdala and fear conditioning?
Low road (be fast)
- fast subcortical pathway via thalamus
- rapid detection of threat
High road (be sure)
- slower cortical pathway
- complex analysis of stimuli
What is the most critical region of the amygdala in conditioned fear?
The lateral nucleus
- typically suppressed by the prefrontal cortex
How does the hippocampus mediate conditioned fear learning?
Informs the lateral amygdala about the context of the fear related event
What is an example of a bodily response to emotional stimuli or situations?
Sweating! Heightened arousal = more sweat
How do we measure sweat levels?
Measuring skin conductance response (increased electrical conductivity) - electrodes on finger
Explain the case study SP
Lateral amygdala damage due to lobectomy to relieve epilepsy
unable to recognise fearful faces
did not acquire CR in fear conditioning (skin conductance level experiment) - she didn’t show a change in sc during learning stage but figured out that she would get a shock. amygdala important for IMPLICIT aspect rather than explicit (she knew facts) aspect
Skin conductance experiment again but given explicit instructions ‘when you see a blue square, you will get a shock’
Normal participants show an increase in skin conductance when the blue square is presented - correlated with greater activation in the amygdala
Those with amygdala damage do not show this response - don’t show increased skin conductance response when the blue square is shown
Emotional memories?
Often the most enduring and vivid - evoke arousal
How does arousal influence morris water maze performance in rats?
Learning in rats is demonstrated using the morris water maze (spatial abilities and memory) show improvements when aroused
- this doesn’t happen if lesions to the amygdala (involved in enhancing the learning)
When people recall emotional memories, what is seen neurologically?
Increased connectivity between the amygdala and the hippocampus
What can extreme arousal or chronic stress do to memory?
It can actually impair it
Due to excessive stress hormones on the hippocampus
What are flashbulb memories?
A flashbulb memory is a highly detailed, exceptionally vivid ‘snapshot’ of the moment and circumstances in which a piece of surprising and consequential (or emotionally arousing) news was learned about.
How does the amygdala enhance attention to emotional stimuli?
By enhancing early sensory processing via feedback projections to the sensory cortex - also if paying more attention to something we are allocating more resources to the stimulus
What is the attentional blink?
A phenomena where if you present 2 stimuli with a gap between them, gradually reducing the gap, when short enough you wont actually see the second stimuli - however emotional stimuli will reduce this and will see the stimuli when you normally wouldnt
(enhancment of attention to emotional stimuli)
Attentional hyper-vigilance when it comes to phobias?
When someone has a particular phobia there is activation in early sensory areas when processing phobia stimuli - allocating more resources to process these stimuli
What can decision making be influenced by and which part of the brain is responsible?
Influenced by emotion - mediated by the orbitofrontal cortex
What is the role of the orbitofrontal cortex?
Understanding rewards and punishment to guide adaptive behaviour
AS WELL AS being associated with experience and anticipation of regret (damage = don’t feel regret or anticipate negative consequences)
Damage to orbitofrontal cortex?
Disinhibited, socially inappropriate behaviours, irresponsibility and poor decision making - also do not tend to learn from their mistakes
Cant responding to changing patterns of reward and punishment
What is the somatic marker hypothesis in relation to decision making
changes in physiological arousal to emotional events (eg. risky situations) are stored as somatic markers in memory
Retrieval (or similar situations) reinstates the somatic markers and guides behaviour (making a response more or less likely)
Form a link between previous experiences and physiological responses
Explain James Gross’s proposed model of emotion (Gross’s model of emotional regulation)
- can be antecedent focussed (reappraisal - reinterpreting the stimulus in non-emotional terms)
or
- response focussed (suppression - trying to inhibit an emotional expressive behaviour)
What parts of the brain are activated when participants are instructed to suppress or reappraise emotional reactions?
Medial portions of the orbitofrontal cortex and cingulate cortex
- may often be accompanied by decreased activation of the amygdala
Stress in the short term?
Adaptive (needing to run away etc)
Stress in long term?
Maladaptive
Other than the HPA axis, what else do stressors activate?
The sympathetic NS
Release of norepinephrine and epinephrine from the adrenal medulla
What is a critique of older animal models looking at stress?
Used levels of stress that may not have human equivalents
What are psychosomatic disorders?
Medical disorders that have psychological causes
What is psychoneuroimmunology?
Study of the interaction of psychological factors, the nervous system and the immune system
Stems from the finding that stress can increase susceptibility to infectious diseases
What is the innate immune system?
First line of defence that attacks generic classes of pathogens - no specific ones
Phagocytes destroy and consume pathogens and release cytokines that trigger inflammatory responses (also attract more phagocytes to the location to help)
What happens if the innate immune system fails?
It is now up to the adaptive immune system
what is the adaptive immune system
targets specific pathogens identified by their antigens (binding to antigens and destroying them or tagging them for destruction from other cells)
- has memory for those that have been found and destroyed previously (basis of vaccines - making system armed to attack this pathogen if needed)
cytokines activate lymphocytes (white blood cells)
- cell mediated (T lymphocytes)
- antibody mediated (B lymphocytes)
Explain cell mediated immunity
Macrophages ingest the microorganism and display its protein on their cell membrane
T cells with an appropriate receptor bind to the macrophage
the bound t cell proliferate and develop into a form that kill body cells that have been infected by the microorganism
Explain anti-body mediated immunity
Foreign antigens are bound by B cells with an appropriate receptor
B cells replicate and develop into a form that releases antibodies to the antigen
antibodies bind to the antigens and kill or deactivate the microorganism
Stress or mistreatment early in life may cause brain and endocrine abnormalities later such as:
Increased risk of psychiatric disorders
Increased intensity of stress response
What part of the brain is particularly susceptible to stress?
the hippocampus
- many glucocorticoid receptors
Therefore…
Stress = disruption on hippocampus related tasks
Adrenalectomy blocks these effects so due to hormones
Where exactly is the amygdala located?
In the temporal lobe at the point where if a line were to go through your eye and through your ear and intercept
