NEURO Biopsychology of emotion, stress and health Flashcards
(19 cards)
What is Darwin’s theory of emotions?
Functions otherwise would have evolved away. Help us build social connections, can help survival. Expressing emotions healthy, emotions give opportunity to connect with others + world around. Help us avoid certain situations. Help us communicate.
-> said all humans have same emotion. Facial expression/ body language gives indication of what going to do next. Clearly important survival mechanisms, things we don’t use we lose.
What two types of changes do emotions cause?
Physiological and biological responses, lead to changes in body you feel.
What are examples of physiological responses to emotion?
Associated with autonomic nervous system. E.g. increased heart rate, breathing, sweating.
What three theories are associated with physiological responses?
-James- Lange Theory: emotions induce sensory stimuli received and interpreted by cortex, triggers changes in visceral organs via autonomic nervous system + in skeletal muscles via somatic nervous system. Autonomic and somatic responses trigger the experience of emotion in brain.
-Cannon- Bard Theory: emotional stimuli 2 independent excitatory effects. Excite feelings of emotion in brain + expression of emotions in autonomic and somatic nervous systems. Parallel processes that have no direct causal relations.
-Modern day view/ two factor theory: each of 3 principal factors in emotional response- perception of emotion- inducing stimulus, the autonomic and somatic responses to stimulus and experience of emotion- can influence the other two. Propose all the aspects interact.
What is fear conditioning?
Fear is easiest way to infer behaviour. Fear often expressed same + plays important adaptive function in motivating avoidance of threatening situations.
What can you say about fear conditioning in animals?
Teaches about neural mechanisms of fear.
Can establish fear in response to previously neutral stimulus (C’s) by presenting it several times, then delivery of aversive stimulus.
Rats hear tone (CS) + recieve mild electric shock (US). After several pairings of tone + shock, rat responds to tone with variety of defensive behaviours (CR).
What can we say about fear conditioning in Humans?
Little Albert.
Preconditioning: white rats (NS) gets neural response of curiosity. Hammer bangs metal pipe (UCS)- instinctual response is (UR).
During Conditioning: NS =UCS paired together. Response of crying from little albert.
Conditioned stimulus (CS): conditioned response (CR) of crying. White rat now eliciting response of fear without the bang.
How is the amygdala involved in fear conditioning?
Amygdala gets input from sensory systems. Structure responsible for learning and retaining emotional significance. Damage/ lesions of amygdala affect fear conditioning.
Many pathways carry signal from amygdala to brain- stem structures that control various emotional responses. E.g. pathway to periaqueductal gray (PAG) of midbrain elicits appropriate defensive response but lateral hypothalamus elicit appropriate sympathetic response- increased arousal.
What is Kulver- Busy Syndrome?
Observed monkey’s anterior temporal lobe removed. Features observed:
-Visual agnosia, increased oral tendency, decresed emotional reaction, hypersexuality, hyper metamorphosis. (MAIN=LACK OF FEAR).
E.g. Patient SM caused by bilateral amygdala destruction.
SM had lower fear than brain damage controls.
How is the limbic system involved in emotions?
Papez- emotional expression controlled by several interconnected nuclei + tracts that ring the thalamus + through action of other structures of the circuit on hypothalamus + that they are experiences through their action on the cortex.
How is the prefrontal lobe involved in human emotion?
Evidence of activity in medial prefrontal lobes when emotional reactions cognitively suppressed or re-evaluated. Hippocampus involved remembering experiences then influence how we behave + respond in future.
How do the areas of the brain work together?
Brain gets input from sensory cortex- input from sense that feed into emotion processing.
Motor cortex involved in how we behave respond or act.
Similar brain activity patterns when person experiences, imagines, sees someone with no emotion.
Motor + sensory cortex active when experiencing or empathising with an emotion.
What other models propose specific roles of each brain hemisphere?
-> Right- hemisphere model: proposes right hemisphere specialised for all aspects of emotional processing; perception, expression and experience of emotion. Suggests right hemisphere plays critical role.
-> Valence model: proposes right hemisphere specialised for processing negative emotions + left hemisphere specialised for processing positive emotions.
-> Current perspectives: emotional situations produce widespread increases in cerebral activity, all brain areas activated by emotional stimuli and during other psychological processes.
How are emotions biologically valuable?
Useful for evaluation, attention, motivation, social connection.
What is stress?
Defined as mental, physical, emotional and behavioural reaction to perceived demands or threats.
-Personal + subjective experience.
-Unusual demand: physical, personal , social (these overlap).
-Perceived as significant or an adversity.
-Responses: physiological, emotional, cognitive.
-Results: adaption (or not) coping failure to cope, cost/ benefit.
What are the mechanisms of stress?
Short term the stress response produces adaptive changes helping animals respond to stressors.
Anterior- pituitary adrenal- cortex gets activated.
Stressors activate sympathetic nervous system, increasing the amount of adrenaline and noradrenaline released from adrenal medulla.
Adrenaline + noradrenaline increase heart rate, breathing, sweating, dilating pupils.
Types of stress: positive, tolerable, toxic.
How is stress and the immune system linked?
Adaptive Immune Response: slower reaction. Specific to antigen.
Innate immune response: response much faster + not specific to any antigen. Responds to all sorts of foreign materials.
What is the difference between adaptive and innate immune responses?
Adaptive Immune Response: presence of antigen e.g. virus or bacteria-> recognition of the antigen e.g. T helper cells, cytokines-> immune system defence response e.g. lymphocytes, NK cells-> antigen defeated-> immune system ‘remembers’ (specific antibodies).
Innate Immune Responses: anatomic barrier (e.g. skin) reacts quickly near to the point of entry-> phagocytes-> inflammation.
Outline the differences between stress, fear and anxiety?
Stress= physiological and psychological response to demands.
Fear= emotional response to perceived or actual threat.
Anxiety= anticipatory response to unknown threat.
