Emotion Flashcards
What is emotion?
Feelings you experience
What does the elevated arm experiment test for?
Anxiety
What does the forced swim test test for?
Depression
What happens in the elevated arm experiment?
Maze with 2 open arms and 2 arms with sides
What are the reactions of normal and anxious mice in the elevated arm experiment?
Normal mice spends more time in the open arms than anxious mice
What happens in the forced swim test?
5 litre beaker full of water
Put mice in and wait till it stops swimming
What do you measure in the forced swim test?
Time it takes the mouse to stop swimming
What does the three chambered box measure for?
Sociability
What happens in the 3 chambered box test?
3 chambers with interconnected doors
In the two end chambers are cages - one with a mouse inside and one empty
What do you measure in the 3 chambered box test?
The amount of time the mouse spends with the other mouse and how long it spends on its own
What are the two theories of emotions?
James- lange and cannon-bard
What is the James-Lange theory of emotion?
we experience emotion in response to physiological changes in our body
What is the cannon-bard theory of emotion?
We can experience emotions independantly of emotional expression
Where is broca’s limbic lobe found?
Primitive cortical gyri that form a ring around the corpus callosum
What does broca’s limbic lobe include?
Parahippocampal, Cingulate and subcallosal gyrus
Medial temporal lobe
Hippocampus
What is the papez circuit?
Limbic structures including the cingulate cortex that are involved in emotion
How does rabies relate to emotion?
Implicates hippocampus in emotion-> hyper emotional responses
What do lesions on the anterior thalamus lead to?
Spontaneous laughing or crying
What are the functions of the limbic system?
attaching a behavioural significance and response to a stimulus, especially with respect to its emotional content
What is the cingulate gyrus’ role in the limbic system?
Complex motor control, pain perception and social interactions
What is the function of the hippocampus proper and parahippocampal areas?
Primary function in memory (critical role in connecting certain sensations and emotions to these memories
What is the function of the amygdala?
Involved in learning and storage of emotional aspects of experience
What are the issues with the single emotion system?
Diversity of emotions and brain activity and many structures are involved in emotion
Where is the amygdala found?
Next to the hippocampus at the base of the third ventricle
What does the amygdala consist of?
Corticomedial nuclei, central nucleus and basolateral nucleus
Where does the amygdala receive input from?
Neocortex
Where does the amygdala output to?
Hypothalamus
Which parts of the hypothalamus do the amygdala reach out to?
Stria terminalis and ventral amygalofugal pathway
What changes when you remove the temporal lobe?
Good visual perception but poor recognition Psychic blindness Oral tendencies Reduced fear Altered sexual behaviour
What happens in a human amygdalectomy?
Reduced fear and aggression Hypersexuality Oral tendencies Reduced ability to recognise a fearful expression Flattened emotions
What happens when you electrically stimulate the amygdala?
Increased vigilance, anxiety, fear and aggression
What is learned fear confirmed by?
fMRI and PET imaging
What are the hormones involved in aggression?
Testosterone
What are the two types of aggression?
Predatory aggression and affective aggression
What is predatory aggression?
Attacks made against a member of a different species to obtain load
What is affective aggression?
Threatening posture to maintain social hierarchy
What is the surgery to reduce aggression?
Amygdalectomy or psychosurgery
What are the effects of amygdalectomy?
Reduction in aggressive behaviour and anxiety
What are the neural components of anger and aggression beyond the amygdala?
Hypothalamus, serotonin and cerebral cortex
What does removal of cerebral hemispheres but not the hypothalamus lead to?
Sham rage
What is sham rage?
Massive anger/ aggression
What does electrical stimulation of the hypothalamus lead to?
Affective and predatory aggression
What are the two hypothalamic pathways to the brainstem involving autonomic function?
Medial forebrain bundle -> VTA
Dorsal longitudinal fasciculus -> periaquiductal gray matter
Which hypothalamic pathway results in which type of aggression?
Medial forebrain bundle = predatory aggression
Dorsal longitudinal fasciculus = affective aggression
What is the serotonin deficiency hypothesis?
aggression is inversely related to serotonergic activity
Which agonists decrease anxiety and aggressiveness?
5HT 1A and 1B
