UPDATES
Quiz 1 will be graded and returned Feb. 24
NO CLASS FEB. 26 – HARBER AT CONFERENCE
Anything Strange about
Strange Situation?
Mom leaves kid.
Kid acts unconcerned
Mom returns to kid.
Kid still unconcerned
Attachment explanation?
Insecure/avoidant:
mom messed up
Alternative explanation?
Kid was born that way,
Temperament
Temperament
Aspects of behavior and emotion that are:
1. Constitutional (in-born, genetic)
2. Stable across time and situations
3. Neurophysiologically based
How Stable is Temperament?
In early infancy –
Correl. 6 mos. To 9 mos.
Smiling, Laughter:
r = .48
Fear:
r = .37
Distress re. Limits (Anger):
r = .51
Easy/Difficult At:
3 yrs
Easy/difficult as an adult
r = .31
4 yrs
r = .37
5 Yrs
r =.15
Is Temperament Genetic?
How would this be tested?
With what kind of population?
Twins
Monozygotic (MZ)
Share all genes: identical
Dizygotic (DZ)
Share half genes: Not identical
Pictures of DZ Twins
Results of Twin Studies and
Temperament (Metheny, et al., 1981)
6 mos
Hurt Feelings
2 yrs
MZ
DZ
MZ
DZ
NA
NA
.37
.13
Tantrums
.39
.26
.41
.15
Irritability
.45
.29
.46
.28
Crying
.62
.51
.59
.39
MZ = monozygotic, “identical twins”
DZ = dizogotic, “fraternal twins”
Temperament and Strange Situation
Temperament may explain Strange Sit. better than
attachment.
Irritable newborns insecurely attached
Neurophysio-reactive  ambivalent
Interest in objects vs. people  avoidant
Interactive explanation
Parents respond to newborns temperament
Parent either flexible or inflexible to baby temp.
Baby’s emotional profile reflects “goodness of fit”
Physiology of Emotions I
Class 8
Approaches to Emotions So Far
Philosophical (Spinoza, Jefferson, Des Cartes)
Evolutionary (Ekman)
Cultural (Culture of Honor)
Conceptual (defining emotions)
Developmental (Attunement, Attachment)
Ole and Sven and Trabatt
Functional Diagram of Brain
Limbic System
How do we know how the brain works?
fMRI
a. Anatomy
b. Lesions
c. Stimulation
d. Recording
Electroencephalogram (EEG)
...functional Magnetic Resonance Imaging (fMRI)
...Transcranial Magnetic Stimulation (TMS)
EEG
TMS
TMS Stimulation and Self Recognition
Decety & Sommerville, 2003
Subject
Familiar
other
TMS stimulation of Right Hemisphere suppresses ability to
recognize self in self/other morph
Early Explorations of Brain and Emotions
Descartes: Reflex Theory (1650s)
Events  sensory receptors  message to brain via
nerves.
Strings in motor nerves open valves, send fluid
through nerves that inflate muscles.
Degree of response proportional to magnitude of
event. (But, who/what determines “magnitude”?)
Implications of Descartes:
* Behavior dictated by environmental prompts
* No role for planning, values, in guiding behavior
* Emotions not even mentioned
Cannon/Bard Theory of Emotions
Cannon and Bard (1930s)
* Believe in central controller of emotions
* Remove neocortex from cats
* Cats display “sham rage”
* Suggests that neocortex guides, controls
emotional behavior.
Cannon’s “Organizational Chart”
Model of Brain Functions
CORTEX
governs
EMOTIONAL STRUCTURES
govern
SIMPLE REFLEXES
“Evidence”:
Phineas Gage, drunkenness, sham rage
Implications:
Emotions have specific location
Emotions undifferentiated; depend on cortical control.
Modern Views of Emotional Brain
(Papez, 1930s and MacLean, 1990s)
Hypothalamus --> Emotional EXPRESSION
Other regions --> Emotional EXPERIENCE
Thalamus is routing station of events:
Info not always processed top-down
Limbic system is seat of emotions
Brain organized in terms of function, not structure
MacLean’s “Routing System” Model
of Brain Functions
Neocortex (thought)
Stimuli
Hypothalamus
Limbic System (feeling)
neocortex
Striatum (movement)
striatum
Major Divisions of the Forebrain
Main Divisions of the Brain
Striatal system:
Reptilian brain
neocortex
Limbic system:
Emotional center
Neocortex:
Reasoning
striatum
Striatal System
Reptilian in origin
MacLean extensively studies lizards to learn about the
functions of striatum.
Basic survival functions: hunting, territorial, mating,
four basic communications:
Self Identification: Hey, it’s me.
Territory: Don’t lean on my wheels
Courting: Hey bayybee, hey bayybee
Surrender: Oh gee, Officer, was I really going 95?
Differences Between Lizards and Mammals
Mammals
Maternal care-giving
X
Vocalizing
X
Play
X
Terrorize Tokyo when fully grown
Lizards
X
Limbic System in mammals provides for these unique abilities.
Limbic System
Evidence That Limbic System Regulates Behavior
Electrode Studies (Hess, 1940s)
1. Superfine electrode stimulation of rats' limbic system
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 (recall mere exposure?)
3. Makes first assessment of event’s emotional significance
4. Neural pathway to amygdala bypasses cortex
Klϋver-Bucy Syndrome
Removal of monkey amygdala leads to:
1. Lose fear to and 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:
neoco
rtex
SENSORY  THALAMUS  AMYGDALA
striatu
m
HEMISPHERE LATERALIZATION
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
Chimeric Faces
Hemispheric Damage and Lie Detection
Who would be better able to detect liars?
X People w’ damage to rational centers?
People w’ damage to emotional centers?
Study of patients with L vs. R hemisphere damage (e.g., due to
strokes, accidents)
L-Hemi damage (use only emotional R Hemi) do better than RHemi damage AND do better than normals (no damage).
Neurological Development and the
Limbic System
R-Hemi 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?
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Evolution and Emotions