Emotions, Aggression, and Stress Flashcards
Final Exam
What is an emotion?
- Subjective mental state usually accompanied by distinctive behaviors, feelings, and involuntary physiological changes (ex. rapid heartbeat, tears, blush caused by autonomic nervous sytem)
What do emotions facilitate?
Social contact and learning
How many core emotions are there?
there are 6-8 core sets of emotions w various degrees of intensity
What are the high level of intensity emotions?
Ectasy, adoration, terror, amazement, grief, loathing, rage, and vigilance
What are the medium level of intensity emotions?
Joy, affection, fear, surprise, sadness, disgust, anger, expectation
What are the low level intensity of emotions?
Happiness, regard, apprehension, distraction, pensiveness, boredom, annoyance, alertness
How is emotion communicated?
- through verbal communication (words, tone of voice)
- and non-verbal communications (body language, facial expressions)
What is the purpose of facial expressions?
Facial expressions provide emphasis and context for verbal communication to your audience
Do people around the world agree on human emotions?
- There are both biological and cultural influences but there is agreement about the meaning of most facial expressions
- Happiness is the most agreed upon emotion
- Non-literate isolated groups had trouble with disgust and surprise recognition
Individual variability
What percentage of infants had low and high reactivity?
- Reactivity was measured in 4 month old infants
- Low reactivity seen in around 40% of infants
- High reactivity seen in around 20% of infants
Individual variability
What are high reactive children biased to become?
- timid, shy, cautious in unfamiliar situations (risk averse)
- greater risk for anxiety disorders
- exaggerated amygdala response
Individual variability
What are low reactive children biased to become?
outgoing, spontaneous, and fearless
What is intra-cranial self stimulation?
- A type of operant conditioning where stimulation of certain brain region may be reinforcing or aversive
- Reinforcement may or may not correlate with subjective pleasure
How is the medial forebrain bundle related to emotions?
- Positive emotion is elicited by stimulating the medial forebrain bundle (anials will work hard to recieve mild stimulation here)
- The VTA area releases dopamine into the nucleus accumbens
- Researchers have proposed that drugs of abuse are addictive because they activated these same neural circuits with an artificial intensity
Papez circuit-limbic system
What does stimulating the limbic system elicit?
negative emotion
Papez circuit/limbic system
What happens when you lesion an overactive amygdala?
- increased social affiliation
- decreased anxiety
- increased confidence
What is the central amygdala a hub for?
anxiety, stress, fear, and addiction
What causes kluver-bucy syndrome and what are the symptoms?
- Caused by lessions/removal of portions of temporal lobes (esp amygdala and hippocampus)
- Symptoms include: dramatically lessened fear and aggression, blunted affect (decreased ability to express emotion), hyperorality, hypersexuality, and visual agnosia (inability to recognize or interpret visual info)
What were patient S.M’s symptoms?
- developed fearlessness in childhood
- outgoing, but few good friends
- confronts risk
- normal nervous system responses
- unafraid of spiders/snakes
- little social fear or sense of personal space
- no (or very low) normal sympathetic nervous system response to nromally fear-evoking stimuli
What does the amygdala “low road” do?
- direct projection from the thalamus to the amygdala
- bypasses conscious processing and allows for immediate emotional reactions to stimuli
What does the amygdala “high road” do?
- routes incoming info through sensory cortex, allowsing for processing that is slower, but is also conscious, fine-grained, and integrated with higher-level cognitive processes (like memory)
- contributions from prefrontal cortex and anterior cingulate offer an additional level of fear conditioning called observational fear learning (when fear of potentially harmful stimuli is learned through social transmission)
What detects external threats?
the amygdala
What detects internal threats?
the brainstem
Brain regions during sadness
- anterior cingulate cortex activity increases
- posterior cingulate corex activity decreases
- dorsal pons activity increases
- insula activity increases
Brain regions activated during happiness
- right posterior cingulate cortex activity increases
- left insula activity increases
- left anterior cingulate cortex activity decreases
Brain regions activated by fear
- midbrain activity increases
- orbitofrontal region of prefrontal cortex activity decreases
Anger brain regions
- pons activity increases
- left anterior cingulate cortex activity increases
What happens during the initial response to stress?
- The hypothalamus activates the sympathetic nervous system to stimulate many phsiological systems, including the adrenal medulla which releases norepinephrine, works quickly
- Hypothalamus also stimulates the anterior pituitary to release hormones that drive the adrenal cortex to release cortisol, works slowly (known as Hypothalamus Pituitary Adrenal axis)
How do norepinephrine and ephinephrine levels respond to stress?
both increase when stressed
Autonomic Nervous System
- Sympathetic: fight or flight, governed by norepinephrine
- Parasympathetc: relaxation, governed by acetylcholine
- Parasympathetic and sympathetic often oppose each other
What does the adrenal cortex/adrenal gland secrete?
steriods, including glucocorticoids
What is cortisol and what does it do?
- Cortisol is a glucocorticoid hormone that prepares the body to deal with stress
- increases blood glucose levels to energize you to respond to the situation you are in
- Also promotes metabolism and suppresses inflammation
What is positive about having early stressful experiences?
can allow for later resilience, known as stress immunization
What happens if you have significant early life stress?
- greater stress responses
- learning deficits
- long-lasting changes in brain steroid receptor expression, driven partly by epigenetic regulation (is where we get individual differences in babies’ reactivity)
What does it mean to have a negative affect?
- experience the world in negative terms
- higher levels of distress, anxiety, and dissatisfaction
- low subjective sense of wellbeing
What increases risk for a negative affective disorder?
- genetic risk: many genes contribute to susceptibility
- chronic, lower grade stressors: increse risk for anxiety disorders/depression
General adaptation to stress theory: Phase 1
Alarm reaction: body mobilizes to confront the threat
General adaptation to stress theory: Phase 2
- Resistance: body actively copes with the threat, has resistance
General Adaptation to Stress Theory: Phase 3
Exhaustion: if the threat continues reserves are depleted, the body “gives up” and can’t do it anymore
General adaptation to stress theory: What happens do to chronic stress?
- chronic stress produces excess alarm and resistance
- contributes to the development of negative affective disorders
What biological markers show there is less adaptation to stress in negative affective disorders?
- People with depression have higher plasma cortisol levels all of the time
- DEX only momentarily suppresses plasma cortisol levels, then they go back to typical high levels
What does DEX do?
suppresses cortisol in typically healthy individuals experiencing a stressful situation
Generalized anxiety disorder
person is always very anxious, baseline is at an anxious level (chronic anxiety, exaggerated tension)
OCD
recurrent unwanted thoughts (obsessions) and/or repetitive behaviors (compulsions)
Panic disorder
- person goes into panic mode much more frequently than healthy individuals
- things that do not typically elicit a panic response will elicit a panic response
- unexpected, repeated episodes of intense fear and physical symptoms
Post traumatic stress disorder
- memories of unpleasant events that produce same intense visceral arousal
- people will have physiological response when placed in similar context to where the traumatic event occured
Social anxiety disorder
- overwhelming anxiety and excessive self-consciousness in everyday social situations
What part of the brain is atrophied in individuals with PTSD?
- the hippocampus
- causal relationship… not sure if PTSD causes hippocampal atrophy or visa versa
How is fear conditioning done?
- Tone is associated with a mild electrical shock
- Eventually tone alone will elicit a freezing response (along with raised BP)
- If tone has a regular pattern, the animal will habituate
- But, chronic unpredictable stressor (tone) will continue to elicit freezing
Model of PTSD
- Original trauma: activates the alarm stress systems and the amygdala
- Subsequent stressors: produce heightened alarm stress response (sensitization)
- This will trigger a traumatic memory via the amygdala
- Over time, traumatic memory associations and physiological response are strengthened
Alarm stress systems acute neurochemical responses:
- Locus coeruleus (norepinephrine)
- VTA (dopamine)
- Endogenous opiods
- Corticotropin-releasing hormone
Reciprocal interactions between these and the amygdala may facilitate the encoding and retrieval of traumatic memories
Depression symptoms
- Unhappy mood
- loss of interests
- loss of appetite and energy
- difficulties with concentration
- restless agitation
Brain changes seen with depression
- Greater brain activity in the PFC and amygdala that persists after depression period is over- electroconvulsive therapy can sometimes revert depression
- Smaller hippocampus
- Reduced monoamine (serotonin, dopamine, and norepinephrine) transmitter activity… why we use SSRIs
What is comorbidity?
- when two disease traits co-occur at a frequency that is higher than expected based upon the base rates of the two alone
- MDD and GAD most common (58% cases are comorbid)
Criticisms of Medical treatments of depression and anxiety
- non-medical treatments (CBT) work
- placebo effects
- medications are not effective in some people
Therapeutics for depression and anxiety
- SNRIs (Serotonin-Norepinephrine Reuptake inhibitors)
- Electroconvulsive therapy
- Ketamine- NMDA receptor antagonist
- CBT
MAOs vs Tri/heterocyclics vs SSRIs
- MAOs inhibit the enzyme monoamine oxidase that breaks down serotonin, dopamine, and norepinephrine
- Cyclics inhibit reuptake of said neurotransmitters (sometimes all sometimes some)
- SSRIs block reuptake of serotonin w little effect on dopamine and norepinephrine
