emotion Flashcards
what is emotion?
a feeling you experience
how can we study emotion?
using human or animal studies
what is meant by manifestation of emotions?
how emotions present on your face - other people can tell how you feel based on the manifestation of your emotions
what is the maze experiment and what does it show?
maze with 2 open and 2 closed arms
- normally, the mouse would feel most secure in the closed arms and it spends most of its time there
- the time the mouse spends in the closed vs open ends gives an indication of how fearful it is
- but, injecting it with diazepam causes it to spend more time in the open ends
what is shown by the forced swim test?
- beaker filled with water, place mouse in it
- mouse will swim for 5-6 mins, then come to an immobilisation point where it doesn’t want to anymore
- the immobilisation point is linked to depressive-like behaviour
- mouse withdrawn from opioids has more depressive-like behaviour
what does the 3-chambered box show?
measures social behaviour
box with 3 interconnected chambers, put a mouse in 1 cage in left chamber and an object in the other in right chamber, and place mouse in the chamber and see where it goes
-mice are social, so it will travel to the chamber with the caged mouse - spend more time in the social chamber
-mouse withdrawn from opioids spends equal time in social and object chambers
what are the 2 theories of emotion?
James-Lange
Cannon-Bard
explain the james-lange theory
experiencing emotions in response to physiological changes in the body
- first we manifest the emotion, then we get the feeling
- eg. seeing a snake, get sweaty palms and racing heart, and then we feel fear
explain the Cannon-Bard theory?
experiencing emotions independent of emotional expression
-experience the emotion, and then this induces manifestation
what is the brain region responsible for emotions?
Broca’s limbic lobe
Broca’s limbic lobe
limbus means border
- hippocampus
- cingulate gyrus (cingulate cortex diff to the rest of the cortex)
- medial surface temporal lobe
- also amygdala is involved in limbic system
what is the parahippocampal gyrus? and what is its role?
grey matter cortical region of the brain that surrounds the hippocampus
-hippocampus and para hippocampus gyrus primary function in memory
what is the cingulate gyrus and its function?
curved fold covering the corpus callosum
- role in complex motor control
- pain perception
- social interactions - mood
explain the papez circuit
look at diagram
neocortex - where emotional colouring takes place
from neocortex to the cingulate cortex, responsible for experiencing emotions
cingulate cortex signals to the hippocampus
hippocampus signals to the hypothalamus via the fornix - emotional expression happens
hypothalamus has ANS and endocrine activation, also activates anterior nucleus of the thalamus which signals to the cingulate cortex - restarts the cycle
cortex role
experiencing emotions
hippocampus role
behavioural expression of emotion
lesions of anterior thalamus lead to
spontaneous crying or laughing
amygdala role
learning and storage of emotional aspects of experience
-fear, anxiety, aggression
in times of sadness, which region of the brain is activated?
frontal cortical regions
in times of anger, which region of the brain is activated?
amygdala
when is the amygdala very hyperactive?
when we feel fear
where is the amygdala located?
close to the hippocampus
what is the amygdala formed from?
many nuclei and sub nuclei
inputs and outputs of amygdala signals?
inputs: hippocampus and cingulate gyrus, cortex - these project to the amygdala
- basolateral, corticomedial and central nuclei receive info
outputs: projections to the hypothalamus via the stria terminalis
what characteristics will a temporal lobe removal cause?
removal of the temporal cortex, amygdala and hippocampus
- reduced fear
- hypersexual
- oral tendencies (putting objects in mouth)
- psychic blindness (seeing objects but not being able to give them any importance)
amygdalectomy
- removal of the amygdala, useful for aggressive people
- reduce fear
- reduce aggression
- reduce ability to recognise a fearful expression (but can recognise happiness)
- flattened emotions
electrical stimulation of amygdala?
- increased vigilance
- anxiety, fear and aggression
explain amygdalas role in memory?
learning of fear and having the memory of this emotion
- forming memories of emotional events
- eg. reliving experiences that are bad, PTSD
explain the 2 types of aggression?
predatory aggression
- no sympathetic activity
- motivation to kill
affective aggression
- high levels of sympathetic activity
- just for show
- social heriarchy
surgery to reduce human aggression?
amygdalectomy or psychosurgery
-relief from anxiety, unpleasant side effects
hypothalamus and aggression?
electrical stimulation of hypothalamus leads to predatory aggression
medial hypothalamus elicits which type of aggression?
medial hypothalamus - affective aggression
periaqueductal gray matter
lateral hypothalamus elicits which type of aggression?
lateral hypothalamus - predatory aggression
medial forebrain bundle, projects to VTA
serotonin and aggression relationship?
aggression inversely related to serotonin activity
5HT antagonist
increases aggression
5HT agonist
decreases anxiety and aggression
