Lecture 11 Flashcards
What is emotion
Unfortunately, one of the most significant things ever said about emotion may be that everyone knows what it is until they are asked to define it. The autonomic nervous system conveys sensory info to the rest of the brain, stimulates reflex actions and is largely unconscious. Emotion is associated with a physiological response that causes action - but does action come before or after emotion. People with paralysis still report emotions but people with autonomic failure report less intense emotions. Induced smiling and frowning increases reported emotion
Where does emotion come from
Feelings cognitions and actions
Discuss the sympathetic branch and parasympathetic branch’s effects on behaviour
Sympathetic = intense, quick responses which increases in heart rate - fight or flight - emergency preparation. Parasympathetic = no emergency preparation, increases digestion and saves energy - calms the body
What brain areas are related to emotion
Emotion systems are sub-cortical and shared with other animals. The limbic system is crucial to emotion and motivation - sensory input, emotional responses to pain and regulates behaviour. There is huge variability in cortical activations when using PET and fMRI scans. Disgust seems to have a clearer cortical basis - insulate cortex = primary taste cortex, if you feel disgusted you see someone else disgust or feel moral disgust. The left hemisphere relates to the behavioural activation system: low/moderate autonomic arousal, left frontal and temporal lobes. Right hemisphere relates to increased attention and arousal with inhibited action, right frontal and temporal lobes: this implies that people with more activity in the left hemispheres are happier and those with more in the right are more withdrawn - but the right is more responsive to emotional stimuli: patients undergoing Wada procedure = right hemisphere is inactivated and they could remember significant events but denied feeling any emotion
What is the function of emotion
Survival responses: fear = run away, anger = attack. Autonomic activity alerts you to a problem before it is consciously registered: lowa gambling task, even if you don’t get the rule you feel more nervous taking red cards - damage to prefrontal cortex or amygdala don’t! So if we analyse similar observable behaviours in other species, that can help us understand a specific function. Bared-teeth display in chimpanzees and the human smile are used for different functions
Why do we blush?
Redding of the face which is associated to embarrassment, Darwin suggested it is uniquely human BUT continuous with social appeasement in non-humans - deflect attention and avoid conflict. Parasympathetic activity = an autonomic attempt to calm the body down
Discuss fear and anger
Often studies together as they seem to be polar opposites, fear associated with escape and anger is associated with aggression - fight or flight.
Discuss aggression
It is heredity and environmentally affected - there may be genetic contribution to violence, monozygotic twins resemble each other more than dizygotic twins in violent/criminal behaviour, and smoking during pregnancy is associated with criminal activity in adulthood. Higher levels of testosterone is linked to criminal convicted of murder or rape. The hypothalamus can induce aggressive attacks from widespread stimulation and intermittent explosive disorder. Aggressive behaviour can also be linked to levels of serotonin release - but mainly based on correlations, there was an increased aggressive behaviour when decreased serotonin in male mice. Monkeys with lowest serotonin were most aggressive and all died young. Depression is also linked with low serotonin but not violence, and serotonin is released during aggressive behaviour
Discuss fear
Are animals born with innate fears? The startle reflex = response to a sudden loud noise and leads to muscle tension in the neck - amygdala damage disrupts the startle reflex by not altering the response but by impairing the animals ability to learn which stimuli are scary - thus the amygdala enhances the startle reflex by helping conditioned responses to form. Sensory info goes to the amygdala in the midbrain and pons. Toxoplasma are parasites that reproduce in cats and infects rats and migrates to the brain and damages the amygdala and this results in the rat not fearing properly and approaches cats and gets eaten. Kluver-Bucy Syndrome is where the amygdala is damaged produces tame and placid monkeys and approaches snakes and dominant monkey - rhesus macaques have a very strict dominance hierarchy so they sank to the bottom of the group BUT the monkeys were less afraid of approaching experimenters and seemed to increase their motivation to approach and explore. The amygdala seems to be involved in emotional processing in general in humans and responds when people look at emotional expressions thus associated with felt emotion. Amygdala responds to emotional stimuli that isn’t identified consciously; stimuli flashed briefly - but no conscious response but autonomic responses are triggered. But fear depends on gaze direction of expression and is important to work out whether someone is directing their emotion at you. The amygdala seems to respond the most when fear is direct, and anger is averted = the amygdala is active when emotional processing is more complex?
What happens to fear when the amygdala is damaged
People still feel emotion, but struggle with interpreting emotional info when it is ambiguous or subtle, for example we make judgments about trustworthiness - people with amygdala damage regard faces the same and not form judgments about people. Patients with amygdala damage couldn’t depict fear and have impairment seems to relate to attending to the eyes
