PSY 351 exam 3

Emotion

subjective mental state that is usually accompanied by distinctive cognition, behaviors & physiological changes

• sensations accompanying them are the result of autonomic nervous system

Motivation

psychological process that induces/sustains a particular behavior

James-Lange theory (wrong)

suggested emotions we experienced are caused by bodily changes

• but many failures to link specific emotions to specific bodily responses

• no distinctive autonomic pattern for each emotion

Cannon-Bard theory

• brain decides which particular emotion is an appropriate response to stimuli

• cerebral cortex simultaneously decides appropriate emotional response & activates autonomic nervous system to appropriately prep bod

Cognitive attribution theory

emotional labels are attributed to relatively nonspecific feelings of physiological arousal

• specific emotion we experience depends on interaction between physiological arousal & cognitive interpretation of concurrent context

Individual response stereotypy

emotional reactivity & physiological responses expressed by individuals in emotional situations

• these patterns remain stable throughout lifespan

Core set of basic emotions

certain expressions appear to be universal among people of all regions of the world

• nonhuman animals may show comparable expressions of some emotions

Program fear

evolved through natural selection

• focus on avoiding danger & seeking safety

• suppress other activities

Emotions as evolved preprogramming

helps us deal quickly & effectively with wide variety of situations

• could be important to recognize emotions in other people

Plutchik’s eight basic emotions

grouped in 4 pairs of opposites

1. joy/sadness

2. affection/disgust

3. anger/fear

4. expectation/surprise

all other emotions arise from combinations of this basic array

Ekman et al (facial expression detection)

there are distinctive expressions for various emotions, which are interpreted similarly across many cultures without explicit training

• anger

• sadness

• happiness

• fear

• disgust

• surprise

• contempt

• embarrassment

Facial muscle nerves

innervated by 2 cranial nerves

1. facial nerve (VII)

2. motor branch of trigeminal nerve (V)

governed by face area of motor cortex

Facial nerve

innervates superficial muscles of facial expression

Motor branch of trigeminal nerve

innervates muscles that move jaw

Face area of motor cortex

disproportionately large brain region in humans that governs cranial nerves in facial expression

• may reflect the importance of emotional expression in humans

Facial feedback hypothesis

suggests that sensory feedback from facial expressions can affect our mood

• consistent with James-Lange

Septum

region of brain where animals in experiments give themselves electrical stimulation

Brain self-stimulation

process in which animals will work to provide electrical stimulation to particular brain sites, presumably because experience is very rewarding

• works in humans too

• may tap into dopaminergic circuits that are normally activated by behaviors that produce pleasurable feelings

Medial forebrain bundle

collection of axons travelling in midline region of forebrain

Nucleus acumbens

region of forebrain that receives dopaminergic innervation from VTA

• often associated with reward & pleasurable sensations

Decorticate rage

sudden intense rage characterized by actions that lack clear direction

• snarling, biting in dogs

• aka sham rage

• when cerebral cortex is removed

Limbic system

loosely defined, widespread group of brain nuclei that innervate each other to form a network, implicated in emotions

• mammillary bodies of hypothalamus

• anterior thalamus

• cingulate cortex

• hippocampus

• amygdala

• fornix

Klüver-Bucy syndrome

• caused by bilateral amygdala damage → dramatic emotional changes

• reduction in fear, anxiety & aggression

• strong oral tendencies

• frequent & often inappropriate sexual behavior

Fear conditioning

form of classical conditioning in which previously neutral stimulus is repeatedly paired with unpleasant stimulus, until previously neutral sitmulus alone elicits responses seen in fear

• amygdala governs this

Lesion to central nucleus of amygdala

prevents blood pressure increases & freezing behavior in response to conditioned fear stimulus

Appetitive learning

conditioned positive emotional reactions to attractive stimuli

• amygdala governs this

Thalamus & emotions

sensory information about emotion-provoking stimuli reaches thalamus, which projects to amygdala

Low road

direct projection from thalamus to amygdala for emotional responses in original fear-conditioning studies

• bypasses conscious processing

• allows for immediate emotional reactions to stimuli

High road

routes incoming sensory information through sensory cortex

• slower but conscious, fine-grained processing

• integrated with higher-level cognitive

Capgras delusion

believing their significant other has been replaced by imposter

• more typically psychiatric symptom

• but some cases are thought to result from brain damage that robs afflicted person of low-road connection between visual stimuli & the emotions they would normally elicit

Aggression

behavior intended to cause pain/harm to others

Intermale aggression

aggression between males of same species

• observed in most vertebrates

• adaptive for gaining access to food & mates

• seem to be affected by androgens

Aggression & testosterone in men

• aggression increases markedly in many species at sexual maturity (secreting testosterone)

• experience can potently affect testosterone levels (decreasing for losing males, increasing for females independent of outcome)

• dominance as confounding variable

Proactive aggression

behaviors that confer/protect individual’s social status

• part of offensive strategy to improve individual’s standing in comparison to others/achieve desired social outcome

Reactive aggression

encompasses many forms of defensive behavior that protect against external threats

Brain circuits mediating aggression

• dopamine

• GABA (more = less aggressive behvaior for most)

• vasopressin

• serotonin especially (more = lower aggression)

Optogenetic experiments

light is used to activate neurons in genetically modified mice

Medial amygdala, mPOA & aggression

• medial amygdala analyzes olfactory & pheromonal info, allowing male rodents to distinguish between male rivals & females to be courted

• this info is relayed to VMH which serves as trigger to activate aggressive behavior

Maternal aggression

aggression of a mother defending her nest/offspring\

• VMH

• POA

• premammillary nucleus

• sertonergic projection originating from midbrain

Psychopathy

cluster of personality traits associated with

• superficial charm

• lying

• low empathy

• diminished remorse

• abnormalities in structure & function of emotion processing networks in brain

Stress

any circumstance that upsets homeostatic balance

Alarm reaction

initial response to stress

• hypothalamus activates sympathetic nervous system

• sympathetic nervous system stimulates adrenal medulla to release epinephrine (adrenaline) & norepinephrine

• hypothalamus also stimulates anterior pituitary to release ACTH, which then stimulates adrenal cortex to release adrenal corticosteroids (incl. cortisol)

Adrenal medulla

inner core of adrenal gland

Cortisol

a glucocorticoid stress hormone of adrenal cortex

Adrenal corticosteroids

• act more slowly than epinephrine

• also ready body for action, including releasing body stores of energy

• glucocorticoid receptors respond to them

Glucocorticoid receptors

• found in many locations in brain

• facilitate formation of memories associated with stress & fear

• regulate ongoing secretion of stress hormones via negative feedback

Stress immunization

a little stress early in life seems to make animals more resilient to later stress

• must be accompanied by receiving comfort from mothers after stress

• mothers stroke & lick → gentle tactile stimulation

Maternal deprivation & stress response

if pups are deprived of mother for long periods/receive very little of her attention, as adults

• greater stress response

• difficulty learning mazes

• altered patterns of stress hormone receptor expression in hippocampus

• reduced hippomcampal neurogenesis

Epigenetic regulation

changes in gene expression that are due to environmental effects rather than to changes in nucleotide sequence

Psychosomatic medicine

field of study that studies distinctive psychological, behavioral & social factors that influence individual susceptibility/resistance to diverse illnesses

Health psychology

emphasizes role of social factors in cause, progression & consequences of health & illness

Psychoneuroimmunology

study of immune system & its interaction with nervous system & behavior

Immune system when stressed

compromised during stress & depression, if sustained could increase susceptibility to various diseases

• adrenal steroid directly suppress immune system to redirect resources to the “emergency” at hand

• adrenal steroids also suppression inflammation of injuries

Relaxation training

focusing attention on something calming while becoming more aware of body, trying to relax muscle as much as one can

Delusions

false beliefs strongly held in spite of contrary evidence

Schizophrenia

severe mental illness characterized by negative symptoms + positive symptoms + cognitive symptoms

• has a heritable component

• additionally influenced by environment e.g. stress, pregnancy complciations

Concordance

sharing of characteristic by both individual in a pair of twins

Ventricular abnormalities in schizophrenia

most have enlarged cerebral ventricles, especially lateral ventirvles

• benefit less from anitpsychotic drugs

• mutant version of DISC1 protein causes this

DISC1 protein

normally regulates trafficking of molecules within neurons

Hypofrontality hypothesis

idea that schizophrenia may reflect underactivation of frontal lobes

• neurons in frontal cortex have dendrites with reduced density of synaptic spines

• drugs that alleviate symptoms are associated with increased activity in frontal cortex

Lobotomy

surgical separation of a portion of the frontal lobes from the rest of the brain

Chlorpromazine

early antipsychotic drug that revolutionized treatment of schizophrenia

Dyskinesia

difficulty/distortion in voluntary movement

Tardive dyskinesia

associated with 1st-gen antipsychotic use

• involuntary, repeptitive movements, especially of face & mouth

Supersensitivity psychosis

exaggerated “rebound” psychosis that may emerge when doses of antipsychotic meds are reduced

Problems with dopamine hypothesis of schizophrenia

• no correspondence between speed with which drugs block dopamine receptors & how long it takes for symptoms to diminish

• 30% of schizophrenia patients don’t respond to dopamine antagonists

Phencyclidine (PCP)

anesthetic agent & psychedelic drug

• makes many people feel dissociated from self & environment

• also psychotomimetic, inducing a state resembling schizophrenia

• NMDA receptor antagonists by blocking central calcium channel, preventing glutamate from having its usual effects

Depression

• unhappy mood

• loss of interests, energy & appetite

• difficulty concentrating

• can occur with no readily apparent stress

• strong hereditary contributions

• sets of multiple genes & environmental factors determine risk

Depression & brain changes

• increased activation in amygdala, especially during emotional processing

• increased activity in frontal lobes during cognitively demanding tasks

• decreased activity in parietal + posterior temporal cortex & anterior cingulate cortex (attention)

• lateral habenula dysfunctional in depression → anti-reward center mediating low mood & loss of pleasure

• smaller hippocampus & lower activation there

Electroconvulsive shock therapy (ECT)

last-resort treatment for unmanageable depression

• strong electrical current is passed through brain

• causes seizure

• may temporarily disrupt key forebrain long enough to allow for neuroplastic remodeling of emotional regulatoin circuits

Repetitive transcranial magentic stimulation (rTMS)

noninvasive treatment in which repeated pulses of focused magnetic energy are used to stimulate cortex through scalp

DBS for depression

mild electrical stimulation is applied to targets in limbic system of brain, via surgically implanted electrodes