physiology of emotions ii class 10. quiz 1 number correct 13-15a 12 a-/b+ 11 b 9-10 b- 8 c 7 d 5-6 f...
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Quiz 1
13-15 A12 A-/B+13 B9-10 B-8 C9 D5-6 F
15 10 pts16 9.3 pts13 8.7 pts12 8.0 pts13 7.3 pts14 6.7 pts 9 6.0 pts
8 5.3 pts7 4.7 pts6 4.0 pts 5 3.3 pts
Evidence That Limbic System Regulates Behavior
Electrode Studies (Hess, 1940s)
1. Superfine electrode stimulation of rats' LS
2. Rats respond to jolts as if hugely rewarding:
a. Go to where jolts occurred
b. Work long to get jolts
c. Learn tasks paired with jolts
3. Refers to this as "self-stimulation behavior"
4. 85% of limbic system --> self stim behavior, rare outside of limbic system
Rats' response to jolts is like what kind of problematic human behavior?
Addiction
More Evidence That Limbic System Regulates Behavior
Psychomotor Epilepsy
1. Occurs when brain cells in certain area fires in waves
2. Psychomotor epilepsy restricted to limbic system
3. Has similar effect in humans as electrode shocks in rats.
4. Results of limbic epilepsy (emotional auras):
a. Happiness: Dostoevsky reports "indescribably happiness."
b. Other emotions: Desire, sadness, affection, fear, anger.
Behaviors associated with P.E. 1. Shadow boxing
2. Kissing fits
Amygdala
1. Emotion central: pleasure and pain
2. Sensitive to unfamiliar stimuli
3. Makes first assessment of event’s emotional significance
4. Neural pathway to amygdala bypasses the cortex
Klϋver-Bucy Syndrome
Removal of monkey amygdala leads to:
1. Lose fear to/aggressiveness towards humans
2. No facial expression
3. Examine things regardless of danger: fire, broken glass
4. Eat everything: meat, feces
5. Mate everything: other sex, same sex, inanimate objects
Klϋver-Bucy Syndrome occurs when amygdala is damaged. Shows same effects in humans as amygdala removal in monkeys.
What does K-B Syndrome say about emotions and judgment?
LeDoux’s Neural Pathways
STANDARD ROUTE:
SENSORY THALAMUS CORTEX AMYGDALA
EMERGENCY ROUTE: SENSORY THALAMUS AMYGDALA
This route indicates what comes first, thinking or feeling?
This route indicates what comes first, thinking or feeling?
Thinking: cortex precedes amygdala
Feeling: Direct line to amygdala
Amygdala and Emotions: Key Points
1. Input connections—Visual centers, auditory centers
2. Output connections—hypothalamus (directs emot. behavior)
3. Activation leads to self stimulation behavior, a range of emotions
4. Assigns emotional significance to events
* Conditioning occurs without cortex, just amygdala
* Directs attention to important events
* Sets up species specific action systems
5. Does amygdala support appraisal or separate systems?
Hemis. Lateralization and Emotions
Lateralization: L hemisphere guides right side of body
R hemisphere guides left side of body
Lateral functions: L hemisphere – speech, reasoning
R hemisphere – emotional recognition and
interpretation.
All reversed if Left-handed (i.e., L hemi. guides emotion, etc.)
Research on hemisphere lateralization
1. Split-brain studies of epileptics
2. Emotional ID of faces and hemi. dominance
3. Lie detection and hemisphere dominance
Split Brain Studies of Epileptics
Epilepsy treatment—removal of corpus collosum
Corpus Collosum is: Membrane connects L hemi to R hemi
Removal permits exclusive presentation to L or R hemi
Patients shown emotional displays to L or R side of brain
Can recognize emotions when shown to:
Can verbalize emotions when shown to:
Right side
Left side
Aphasia and Lie Detection
a•pha•sia (uh-fay'-zhuh) n. An impairment of the ability to use or comprehend words, usually acquired as a result of a stroke or other brain injury (National Aphasia Association).
Oliver Sacks and laughter from the Aphasia Ward during Ronald Reagan’s speech.
Aphasiacs depend on emotional cues
So good at “reading” emotions, hard to see that they don’t understand language.
Respond to HOW things said, not WHAT said.
Valence Lateralization
Emotional Perception: R hemi is superior to L hemi
Does one side FEEL more emotion than the other? NO
Hemis differ in type, or “valence” of emotions they favor.
Negative emotions felt mainly on?
Positive emotions felt mainly on?
Right Side
Left Side
EEG Evidence of Lateralization
EEG = Electroencephalogram
Electrodes placed on scalp, record brain activity
Subjects see funny or gruesome movie, facial expression and EEG are recorded.
Funny Smiling, happy
EXPRESSION HEMI ACTIVATED
Left Side
Gruesome Nose wrinkle, disgust
Right Side
MOVIE
Muscle Contraction and Mood States
Ss contract L-side/R-side of face or squeeze ball in R or L hand.
These actions activate (R-hemi/L-hemi)—per handedness.
These actions, in turn, lead to mood changes:
L-side activity
R-Side activity
Right
Left
Hemi
Hemi
sadness
positive, assertive
Hemispheric Activation and Social Judgment: TAT Study
TAT = Thematic Apperception Test
People see pictures, and tell stories about them.
Commonly used as a clinical psychology device
L-side activity R-hemi
R-side activity L-hemi
More negative interpretations
More positive interpretations
Why Are Emotions Lateralized?
What kind of emotions leads to approach, positive or negative?
Positive
With which hand to we approach things, Left or Right?
Right (dominant)
Which hemi controls these kinds of emotions, right or left?
Left
Which hemi controls Right hand, Left or Right?
Left
Conclusion: Emotions help guide approach/avoidance
Emotional Lives of Stroke Patients
Stroke to Left Hemisphere ? Depression
Stroke to Right Hemisphere ? Mania
Chronically depressed people show less Left Frontal Activation
Clinical Condition
Neurological Development and the Limbic System
R-Hemi has closer connections to limbic system than L-Hemi.
R-Hemi develops earlier in infancy than L-Hemi
Emotions appear in babies before language
Emotionally expressive babies start talking later
When babies start to talk, don’t show emotion
13 mos—talk, no emotion
19 mos—talk + emotion
What does this say about separate systems?
Are Affective Styles Genetic? Davidsons, Kagan et al. 1993
Subs: 2.5 year olds (N = 386) tested with moms present.
Start (“T”): Hang out with mom
T + 10: Talking robot appears
T+ 13: Robot leaves to “take a nap”
T+ 20: Stranger with fun toys “Want to play?”
T + 23: Stranger leaves
Three types of children identified:
1. Inhibited: hover near mom, quiet, avoid robot, stranger
2. Un-inhibited: Less time w’ mom, engage in activities
3. In-betweeners: Between inhibs and un-inhibs
Hemisphere Activation and Temperament:Kagan, et al. Study of Inhibited/Uninhibited Kids
-0.06-0.04-0.02
00.020.040.060.08
0.10.12
Inhibited Middle Uninhibited
Lowe
r = R
ight,
High
er =
Lef
t
Implications for shyness: Learned or inherited?
Hemisphere activation measured using?
OTTO LOEWI AND THE DISCOVERY OF NEURO-CHEMICALS
Heart #1 Heart #2
1. Stim vagus nerve, slows Heart 1 (H1)
2. Extract fluid from H1 bath
3. Apply H1 fluid to H2.
What happens to Heart 2? It slows. Why? Acetyl-choline
Neurochemicals and Emotions1. Neurotransmitters (e.g., acetyl-choline)
2. Hormones (e.g., adrenaline, from adrenals)
3. Neuromoderators (e.g., endorphins)
Relevance to emotions
* Different emotional systems employ different neuro-chemical messengers
* Different chemicals lead to different emotional states
* What clinical value in locating "emotional" chemicals?
Discovery of psychotropic drugs to treat: depression, anxiety, hyper-arousal.
L-Dopa
1. Pre-cursor to dopamine, a neurotransmitter
2. Acts on striatum—motor activity
3. “Re-awakens” sleeping sickness patients
Revived planning, spontaneous action
Revived emotions--probably b/c revived striatum communicates with ???
Awakenings, (1990)
Amygdala
Panic Attacks
Sudden rush of fear, lasts 15-30 minCome "out of the blue"Feels like heart attack, will lose controlCan lead to agoraphobia--fear of being in the open