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Affective Computing
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Lecture 3
Appraisal Theory
Appraisal Theory:
Stimulus ➞ Cognitive Appraisal ➞ Emotion
But is emotion always post-cognitive (require cognition)
Zajonc: Rejects that Affect is
Post-Cognitive
• Zajonc, 1980
– Rejects Cognitive Appraisal View that
presumes (cognitive) appraisal precedes
affective reactions
Zajonc View: The Basis
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Affective Reactions are primary
Affect is basic (universal)
Affective reactions are inescapable
Affective judgments tend to be irrevocable
Affective judgments implicate the self
Affective judgments are difficult to verbalize
– Cf non-verbal
• Affective reactions need not depend on
cognition
• Affective reactions may become separated
from content
Zajonc View: Evidence
• Affective Reactions show phylogenetic and
ontogenetic primacy
• Separate neuroanatomical structures can be
identified for affect and cognition (1984)
• Appraisal and Affect are often uncorrelated and
disjoint
• New affective reactions can be established without
apparent participation of appraisal
– Taste aversion
– Repeated exposure preferences w/o recognition
• Affective states can be induced by non-cognitive and
non-perceptual procedures
– Drugs, hormones
– Facial action such as smiling (Ekman et al)
Preference vs Familiarity
– We like things we have seen or heard before
• Novelty also key component of appraisal
• Does it hinge on subjective recognition
– Experiments:
• Dichotic listening experiment (Wilson)
• Rapid (1ms) random polygon presentation
– Results:
• Liking w/o subjective recognition
• Liking is better than “conscious” recognition at
distinguishing old and new stimuli
• Subjects far more confident of their liking judgments
• Affective judgments faster
• Novelty/familiarity not mediating affect
– Your first guess is your best guess
Comments
• Zajonc blurs cognition & consciousness
– Cognitive Appraisal: Subsuming of
cognition by emotion
• Key question remains:
– how do cognition and emotion interrelate
• Point to remember
– Does appraisal require cognition or
inference at all
Affective Neuroscience
Basic Circuits /
Emotion Categories
• Jaak Panskepp
• Basic, distinct emotion circuits in the brain
– Distinct emotional patterns can be evoked by
stimulating electrically particular subcortical areas
responsible for basic emotions
• Cortical regions largely free of such effects
• “Essence of emotionality is subcortical and
precognitively organized”
– Nevertheless cortical appraisal and memory
processes modify and are modified by emotions
– No emotional state is free of cognitive influence
Emotion rooted in ancient
recesses of mammalian brain
Evolution adds layers that mediate stimulus and response
by more sophisticated sensory processing, learning & memory
Evolution
Note : Lisencephalic mammals have smooth cortexes while
primates have folded cortexes with more surface area
(allows more neurons)
Alternative views on role of
affective consciousness in
emotional adaptation
1. Stimulus ➞ Interpretation ➞ Feeling ➞ Bodily Response
2. Stimulus ➞ Interpretation ➞ Bodily Response ➞ Feeling
3. Stimulus ➞ Interpretation ➞ Bodily Response ➞ Feeling ➞ Attribution
4.
Panskepp’s Psychobiological
View
Cognitive
Perceptual
Process
EMOTIONS
Mediated
Directly
Via
Brain Circuits
Autonomic
Processes
Role: Regulation of response
• Affective experiences are generated by
neuronal mechanisms
• Mechanisms arose to respond to lifeimpacting events over course of evolution
• Beyond reflexive response
– It is more adaptive to anticipate future needs than
simply respond to immediate
– Must adapt both thru evolution and learning
Basic Circuits
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Fear
Anger
Sorrow
Anticipatory eagerness
Play
Lust
Maternal nurturance
Others?
– Ongoing research
Basic Circuits (cont)
Implications
• Basic Circuits – Emotion Categories arise from these circuits
– Guide Responses
• Evolutionary roots
• Potential Impact on learning
– Associative learning probably linked to emotion
circuits
• Ontogenetic effects
Example: LeDoux
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Fear Conditioning in the Rat
Fear Conditioning
• Initially neutral stimulus (conditioned
stimulus) can acquire affective properties if
paired with a biologically significant event
(unconditioned stimulus)
• Pair audio tone (conditioned stimulus) with
electric shock (unconditioned stimulus)
• Rat eventually learns to react aversively
just to tone
• Then study learned pathways and role of
various brain regions via
• Staining of neurons and dissection
• Impact of lesions on behavior
Key to Regions Studied
• Amygdala
– Forms association of tone with reaction
– Part of the cortex (cognitive processing, more
recently evolved area)
– Connects cortical to subcortical (older, reflexive
behavior)
– Has 12 (or more) subcomponents or nuclei
• Thalamus
– Processing of stimuli
• Sensory/Auditory Cortex
– More sophisticated processing/analysis of stimuli
Role of the Amygdala
Role of the Amygdala
Amygdala
• CS: Conditioned Stimulus
• LA: Lateral nucleus of Amygdala
• CE: Central Nucleus of Amygdala (connections to subcortical
areas that control responses)
Hi-Lo Roads
Amygdala
• Low Road:
• Thalamus to Amygdala
• Fast response
• High Road:
• Thalamus to Sensory Cortex to Amygdala
• Slower response, deeper processing of stimulus in cortex
Contextual Fear Conditioning
• Hippocampus also plays role
• Forms memory representations of
different situations.
• Provides amygdala with
contextual information
• Allows response to be conditioned
to given stimulus in given situation.
• Thus emotional reaction will be
appropriate for that context
• Example: Rat’s fear response elicited
when returned to chamber where shock
was delivered
CE
Connections
Studies of Human Amygdala
• Brain Damage
– to Amygdala
• impacts perception of emotional expressions & voices
• Impacts Fear Conditioning
– to Hippocampus
• Impacts fear conditioning to context
• Functional Imaging
– Fearful/angry faces activate amygdala more than
happy ones
– Fear conditioning leads to increased amygdala
activity
Human Amygdala
Pathways to and from cortical regions
Amygdala once activated by sensory
events from thalamus or cortex:
• Regulates cortical areas that
project to it
• Influences cortical sensory
processing thru arousal networks
that innervate cortical areas and
bodily feedback that impacts
cortical area
• Interacts with medial prefrontal
cortex and dorsolateral prefontal
cortex that:
– Influence cognitive function
– Regulate amygdala
LeDoux: Feeling/Conscious
Emotion ?
Caveat: Rat Studies
Points
• Emotions involve primitive circuits
– Preserved across evolution
– Basic Categories
• Coupling between emotion and cognition
circuits is complex
• Components complex
– Amygdala has 12 centers (nuclei)
• Emotion memories versus non-emotional
memories
– Emotional memories persistent
– Non-emotional can extinguish emotional
Points (cont)
• Parallel routes of processing of emotional
stimuli
– Thalamic-amygdala (Fast)
– Cortical-amygdala (likely regulates fast route)
• Separate inputs to emotional eval
– Fear:
• Simple stimuli (LA-CE)
• Complex stimuli (hippocampus-B/AB-CE)
• Emotion expression are triggered centrally
• But specific expressions determined locally
– Lateral hypothalamus - blood pressure
– Gray - freezing