PSYC 276 UNIT 3 Study Guide Flashcards
Why is the idea that we only use “10% of our brain” a neuromyth?
We use our entire brain. There is no evidence for unused capacity in the brain, though we do not use all of the brain at the same time (e.g., stoplight)
Extra info:
if you think about development, any neurons that are not used die off. That said, we do not only use all of the brain at the same time (like a stoplight, only some portions are “on” at a time).
circuit of brain regions active when we are mentally inactive
Default Mode Network
Extra: This is NOT active when we are intentionally doing something or thinking.
surgery that physically removes on hemipshere (primarily the cortex)
hemispherectomy
Extra: Some tissue is still left intact. If young enough, brain plasticity is better able to rewire itself to perform functions of removed hemisphere.
new connections are made between active neurons to create alternate neural pathways
different part of brain takes over task that damaged part usually does
Rerouting
new axon and dendrite extensions “sprout” and allow existing neurons to form new connections.
Sprouting
When would collateral sprouting be considered good, neutral, and negative?
good = replaces broken pathways
neutral = might not do anything
negative = collateral path may result in chronic pain
What are two ways the brain rewires itself after injury?
sprouting and rerouting
What therapies support the process of the brain rewiring itself after damage?
Physical and cognitive therapies (e.g., video games, exercise, language therapy)
Medication (drugs, esp. stimulants, may accelerate activity in healthy brain regions after stroke)
sharp blow to the head that does not puncture the brain
most common brain injury in young adults
closed head TBI
Why are closed head brain injuries difficult to treat?
(Coup/contre-coup) Bruising occurs at the site of impact and site of reverberation (where brain hits other side of skull)
temporary loss of blood flow of the brain
stroke
most common type of stroke resulting from blood clot or obstruction of an artery
nutrient supply is stopped and cannot get to areas of the brain
ischemic stroke
less common type of stroke resulting from ruptured artery
neurons at site of rupture are flooded with excess blood, calcium, oxygen, and other chemicals AND neurons at the end of the blood’s intended pathway are deprived of necesary nutrients
hemorrhagic stroke
Two effects of a stroke
edema and disruption of NA/K pumps
fluid accumulation, increased pressure on brain, can cause cell death
edema
effect of stroke
accumulation of NA and K ions cause hypopolarization (reduced polarization, inside of cell becomes less negatively charged and leads to more action potentials) leading to NA build up and cell death
Disruption of NA/K pumps
List the main symptoms of stroke.
BEFAST
- Balance (loss of balance)
- Eyes (loss of vision)
- Face (facial drooping)
- Arm (weakness in arm)
- Speech (difficulty with speech, slurred)
- Time (Call 911 ASAP)
3 treatments for stroke
- Cooling the brain to minimize damage – theoretically protects brain after ischemia by reducing overstimulation, apoptosis, and inflammation; not a ton of evidence for this but it doesn’t cause harm
- Tissue plasminogen activator (tPA) – given within 3 hours (in some cases up to 4.5 hours) to break up blood clots
- Stent – for prevention, done very rarely in high risk people
subjective mental state
emotion (scientific definition)
Behaviors associated with certain emotions have a(n) ———- basis
evolutionary
Main purposes of emotion
- aid in quick decision making
- help communicate needs to others (and understand others’ needs)
Theory of Emotion
We experience an emotion in response to a stimulus, then our body responds. (body’s reaction is determined by emotion)
Folk Psychology
We experience a physiological pattern of arousal in response to a stimulus BEFORE experiencing the emotion. (emotion is interpreted based on our body’s reaction). This is similar to the facial feedback hypothesis.
James-Lange Theory
In response to a stimulus, we experience a particular emotion and general pattern of autonomic arousal simultaneously, BUT these processes happen independently.
Cannon-Bard Theory
We use context to cognitively attribute specific emotions to arousal. (the experience of emotion is still attributed to physical arousal, but context of the situation decides which emotion we experience. NEED TO REVISIT VIDEO
Schachter-Singer Theory
Why might botox injections impact emotion?
Facial feedback hypothesis;
- By paralyzing facial muscles, we have reduced facial expression. This has been reported to cause some people to experience emotions less intensely.
- This is consistent with the James-Lange Theory or facial feedback hypothesis, which implies that sensory feedback from facial expressions can affect mood.
- Physiological and psychological effects can be bidirectional.
When extreme facial expressions were photoshopped onto a body getting piercing versus body winning tennis match, participants’ interpretation of which emotion the photographed person was experiencing depended on:
the context (body positioning, situation)
When multiple brain areas contribute to different patterns of behavior
degeneracy
the ability to recognize facial expressions even when blind
(person can look at a picture and even though they cannot see it, they can gell what emotion the person is experiencing)
affective blindsight
(person is unable to tell WHO is in the picture still)
How is degeneracy different than redundancy?
Degeneracy – different factors and different mechanisms lead to the same outcome (way that system does it is different)
Redundancy – different factors lead to ONE mechanism to the same outcome
surgical disconneciton of the prefrontal cortex
prefrontal lobotomy
Why were prefrontal lobotomies done?
Initially used in treating schizophrenia and depression with self-harm to minimize impulsivity, aggressive behavior, etc. Later was used on people with less severe mental illnesses.
What changes were caused by prefrontal lobotomies?
- While it removed undesirable symptoms, it often also removed emotion entirely (flat affect).
- Apathy
- Lack of ability to plan
- Memory disorders
- Lack of emotional expression
behavior intent on causing pain or harm to others
aggression
Based on studies in monkeys and humans, we know that aggressive behavior is linked to —————-, but are unsure of the direction of this effect.
low serotonin turnover
Post-castration, monkeys show a ——— in aggression. What does this suggest?
decrease; suggests that androgens play an important role in aggression
When monkeys were administered testosterone, —————– increased. Further, ——————— until the subjections stopped receiving testosterone.
aggression; aggression behaviors continued
In humans, what does increased testosterone at puberty case and what does this suggest?
Puberty and the accompanying increase in testosterone does not affect aggression, indicating that other factors are at play in the testosterone/aggression relationship.
For people who scored low on ———– traits, testosterone had no affect on aggression.
dominance
People who ———– and ————–, were significantly more likely to be aggressive.
scored high on dominance traits; had high testosterone
