Emotion & the Brain
Nathan Spreng
August 10
Cognitive Neuroscience: Psy393
Lecture Outline
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Neurobiology of Emotion
Amygdala
Depression
Emotional Executive Functions
Self & Social Cognition
About the exam
Circuitry of Emotion
(A) Orbital PFC in green
Ventromedial PFC in red.
(B) Dorsolateral PFC
(C) Amygdala.
(D) Anterior cingulate cortex.
(E) Insula
• Each interconnected structure
plays a role in different aspects
of emotion
• abnormalities in one or more of
these regions and/or in the
interconnections among them
are associated with failures
– of emotion regulation
– increased impulsivity
– increased chance of aggression
Davidson, Putnam & Larson, 2000
Neurobiology of Emotions
• fMRI activation—many activated sites,
substantial overlap between different
emotions.
• Not one-to-one
• Commonalities: Insula activation—disgust.
Emotional Recollections
Emotional Recollections
Subcortical Structures of the
Limbic System
Kluver-Bucy Syndrome
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Hyperorality
Psychic blindness
Blunted emotions
Hypersexuality
Dietary change
Naturalistic studies: Loss of respect for social
rank, social isolation or socially indiscriminate,
withdrawn, impaired mothering, and death
(Franzen & Myers, 1973)
Afferent Connections
(Aggleton, 1993)
Efferent Connections
(Aggleton,
Amygdala influences object processing in the
ventral stream
The amygdala
modulates
downstream
processing--arousal and attention
to evocative stimuli
-early visual
processing of
emotional faces can be
influenced by
amygdalar activity.
(Aggleton, 1993)
Case Study
• Urbach-Weithe disease
• Bilateral calcification of the amygdala
• Impaired recognition of emotion in facial
expressions (Adolfs, et al., 1994)
• Increased trustworthiness and
approachability of unfamiliar faces (Adolfs, et
al., 1998)
Cerebral blood flow and Affective Stimuli
• Amygdala involved in processing of
emotional facial expressions (Morris, et al., 1998)
• Amygdala (and orbitofrontal cortex) in
pleasant and unpleasant pictures and faces `
(Keightly et al., 2003)
fMRI encoding of emotional events
Amygdala activity
during encoding
associated with
recall of + and stimuli.
(Hamann, 2001)
positive
negative
Amygdalar activity associates with later memory for
individual emotional experience (Canli, et al., 2000)
PET study
• Emotional (negative) relative to neutral film
viewing
– Increased right amygdalar activity
• Partial Least Squares analysis (ANCOVA) and
structural equation modeling
• Significantly increased amygdala influences on
ipsilateral
– Parahippocampal gyrus
– Ventrolateral prefrontal cortex
(Kilpatrick & Cahill, 2003)
PTSD and Memory
• Limbic system activation in
response to vivid
recollection
• September 11th relative to
everyday memory control.
• Right amygdala
• Hypothalamus
– autonomic and endocrine
responses
• Note additional visual
association cortex
activation
PTSD and Memory
• Amygdalar and
visual cortex
activation in
• PTSD memories of
Air Transat
passengers vs.
controls
• In response to
viewing video
recreation of the AT
disaster.
Affective Symptoms of Frontal Lobe
Disorders
• POSITIVE
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Disinhibition
Impulsivity
Vulgarity
Irritability
Emotional liability
Inappropriate laughter,
crying
– Bizarre social behavior
• NEGATIVE
– Apathy
– Reduced initiative
(Abulia)
– Reduced interest in
daily activities/selfcare
– Akinetic mutism
– Social withdrawal
Frontal-subcortical circuits
Alexander, Delong, & Strick (1986); Cummings (1993)
Circuit
Connections
Dorsolateral Superior Parietal, other DLPFC,
premotor
Orbitofrontal Amygdala, cingulate,
anterior/ventral/medial temporal,
insula
Cingulate
DLPFC, VLPFC, Lateral and
medial temporal, hypothalamus,
midbrain, amygdala, insula
Syndrome
Dysexecutive,
Abulic/Depressed
Irritable, impulsive,
environmental
dependency, OCD
Depression,
neurovegetative
changes (medial)
Apathy, indifference
Depression
• Definition (DSM IV-R):
– “...the presence of a persistent negative mood
state occurring in conjunction with an array of
core behavioral symptoms, including
disturbances of attention, motivation, motor and
mental speed, sleep, appetite, and libido as well
as anhedonia, anxiety, guilt, and recurrent
thoughts of death with or without suicidal
ideations or attempts.” (A.P.A.)
Video
Abnormalities in Depression
• Limbic
– anterior cingulate
(from http//www9.biostr.washington.edu/da.html)
Abnormalities in Depression
• Limbic
– anterior cingulate
• Paralimbic
– anterior insula
– ventral frontal
(from http//www9.biostr.washington.edu/da.html)
Abnormalities in Depression
• Limbic
– anterior cingulate
• Paralimbic
– ventral frontal
– anterior insula
• Neocortical
– parietal
– prefrontal
(from http//www9.biostr.washington.edu/da.html)
Lesion-Deficit & Physiological
Studies
• Mood:
– Mapped to limbic and paralimbic areas
(cingulate, insula) and prefrontal cortex ….but
with much variability
• Attention:
– Mapped to right prefrontal, parietal, and dorsal
anterior cingulate regions
Limbic-Cortical Dysregulation
(Mayberg, 1997)
• Similar patter of inter-regional interactions
and regional reciprocity in functional brain
activity inversely associated with:
• Transient normal sadness in healthy adults
• remission of chronic dysphoric symptoms in
unipolar depressed patients following treatment
PET Experiments
• Experiment 1:
– Healthy Adults
– PET scanned: induced sad & neutral conditions
• Experiment 2:
– Unipolar depressed patients
– Remission: dysphoric mood & other symptoms
– PET scanned before, and after 6 week treatment
Results: Experiment 1
• Transient Sadness - Neutral
• Increased Activation:
– Ventral limbic and paralimbic sites (subgenual
cingulate; ventral, mid-, and posterior insula)
• Decreased Activation:
– dorsal cortical regions (right dorsolateral PFC,
inferior parietal, dorsal anterior cingulate,
posterior cingulate
Results: Experiment 2
• Post-treatment - Pre-treatment
• Increased Activation:
– dorsal cortical regions (right dorsolateral PFC,
inferior parietal, dorsal anterior cingulate,
posterior cingulate)
• Decreased Activation:
– ventral limbic and paralimbic sites (subgenual
cingulate, ventral, mid-, and posterior insula)
Areas of Activation
(Mayberg, 1997)
Common Changes
(Mayberg, 1997)
Limbic-Cortical Model:
Negative Mood / Depression
dorsalACC: cognitive
ventralACC: emotional
reciprocal inhibition across tasks
(Mayberg, 1997)
15 minute break
• Evals
Dr. “Zorro”
Executive Emotional Systems
• Orbitofrontal cortex has been associated
with at least three partially dissociable
cognitive systems
• Nonsocial response reversal system (Rolls)
• Somatic Marker hypothesis (Damasio)
• Social response reversal system (Blair)
Dual evolutionary trends in
architectonic development
Inter-trend dimension
– Archicortical (dorsal) trend
– Paleocortical (ventral) trend
Intra-trend dimension
– Increasing laminar definition
from limbic origins to cortical
extent
– Highest forms of
consciousness impaired by
damage to most recently
evolved cortex
Pandya & Yeterian (1996)
Focal cortical contusion
Vessalius (1536)
Courville (1934)
Pandya & Yeterian (1996)
Contusions in these locations regardless of the site of impact
Vascular system
Stuss & Levine (2002)
Functions of the ventral brain
• Monkey studies (Franzen & Myers, 1973; Kling & Steklis, 1976)
– Loss of respect for social rank
– Social isolation, death
• Inhibition (impulse control)
• Learning and reversal of stimulus-reward associations
– Primary reinforcers (rewards): food, sex, social affiliation
• Making and decoding emotional signals
• Self-regulation
• Not assessed in standard laboratory exam
Pathways of the OFC
Rolls, 2000
Inputs and Outputs of OFC
Rolls, 2000
Roll’s Theory of Emotion:
Nonsocial response reversal
• Emotions: states elicited by rewards and punishers
• Reward: something an animal will do for work
• Punisher: something an animal will avoid or
escape from
• Emotions are modulated when a reward or
punisher is received, omitted, or terminated.
• Emotion/motivational state provide an interface
between sensory inputs and action systems.
(Rolls, 1998; 2000)
Roll’s Theory of Emotion
• In orbitofrontal cortex and amygdala,
primary reinforcers are represented.
• Secondary reinforcers learned there.
• Hedonic value of stimuli is processed.
(Rolls, 1998; 2000)
Representation of primary
reinforcers
• Learning trials not necessary
• Taste, smell, objects, faces, texture, touch
• Reward value (not identity) represented in OFC
– Neuronal responses modulated by hunger
• Primary representation precedes secondary
representation (e.g., taste-objects)
• “OFC is involved in emotional responses by
correcting stimulus-reinforcer associations when they
become inappropriate.” (Rolls, 2002)
Visual discrimination reversal
Rolls, 2000
Brain mechanisms underlying
emotion
(Rolls, 1998)
OFC- Neuroimaging findings I
• Four (suite) vs. two (colour) guessing.
– Monitoring reward value of possible responses.
• Delayed matching-to-sample vs. Delayed
nonmatching-to-sample
– Association between stimulus and forthcoming
reward.
• Medial OFC- association between stimuli and
correct rewarded responses.
Reversal of prior stimulus-reward
associations
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Reversal learning
Go-NoGo
Object alternation
Extinction
Delayed match to
sample
• Delayed nonmatch to
sample
When a previously rewarded
stimulus is no longer rewarding
Dealing with ambiguity
• PET
• Eating chocolate past
satiety
• When reward becomes
punishment
• Medial to Lateral OFC
Small, et al., 2001
Functions of the paleocortical
(ventral) trend
Pandya & Yeterian (1996)
• Inhibition (impulse
control)
• Learning and reversal
of stimulus-reward
associations
– Primary reinforcers
(rewards): food, sex,
social affiliation
Inhibition/Impulse Control
• Male subjects viewed erotic film excerpts while they either
– responded in a normal manner (arousal)
– voluntarily attempted to inhibit sexual arousal
• Sexual arousal experienced, activation in "limbic" and
paralimbic structures:
– right amygdala, right anterior temporal pole, and hypothalamus.
• Inhibition of the sexual arousal activation
– right ventral PFC & right anterior cingulate gyrus
– No activation was found in limbic areas
• Emotional self-regulation is implemented by a neural
circuit:
– prefrontal regions and subcortical limbic structures
– under voluntary control
Beauregard, et al., 2001
• Self-regulatory disorder
Levine et al., (1998, 1999, 2000)
– Inability to regulate behavior according
to internal goals and constraints,
especially in unstructured situations
• “Acquired sociopathy”
Eslinger & Damasio(1985)
– An emotion dysfunction defined largely by
emotional shallowness and lack of guilt
Somatic Marker Hypothesis
“We make judgments not only by assessing
probabilities and consequences, but also (and
primarily) by evaluating their emotional attributes”
-- Antonio Damasio
Somatic Marker Hypothesis
• Link between factual knowledge and
bioregulatory states
• During decision-making, emotional and visceral
representations bias decision making
• Representations associated with an option (from
prior experience) are re-activated to bias decisionmaking covertly
• Somatosensory pattern marks the scenario as
either good or bad, allowing the rapid
rejection/endorsement of specific option-outcome
pairs
Iowa Gambling Task
Four decks to pick cards:
• Two decks have high immediate, but low
overall reward (the bad decks: A & B).
• Two decks have a low immediate, but high
overall reward (the good decks: C & D)
• Reward contingencies must be discovered
Bechara et al. (1994)
Iowa Gambling Task
Courtesy of Antoine Bechara, University of Iowa
Iowa Gambling Task
Courtesy of Antoine Bechara, University of Iowa
Iowa Gambling Task
Courtesy of Antoine Bechara, University of Iowa
Iowa Gambling Test
• Patients with VMPFC damage draw excessively
from decks with negative consequences (high
reward/higher loss vs. low reward, lower loss)
• Healthy participant generate high skin
conductance prior to making a bad decision before
knowing the best strategy
• Somatic markers: patients with VMPFC damage
fail to generate skin conductance response in
relation to bad decks
• Patients with non-VMPFC damage can also be
impaired (e.g., Manes et al., 2002)
• Psychopaths impaired
Bechara et al. (1994) Cognition
Social response reversal system
• OFC in response reversal
– Changes reinforcement contingencies
• Social cues in modulating social behaviour
where social rules or expectations have
been violated
Blair, 2001
Social response reversal system
• Angry expressions are known to curtail the
behaviour
– previously experience associated with another
individual's angry responses or other negative valence
expressions
– eg staring expressions of others that can precede a sense
of embarrassment, and perhaps others' disgusted
expressions
• Evolutionary origins:
– regulating behaviour in disputes between conspecifics
– at different levels in a social hierarchy
Social response reversal system
• Neuroimaging: ROFC in processing
angry, but not sad,
facial expressions
• Angry vs. neutral face
• Blair, et al., 1999
Social response reversal system
• Patients who present with reactive
aggression following OFC lesions have
– impaired in processing angry expressions
– and judging the appropriateness of behaviors in
particular social contexts (Blair & Cipolotti,
2000).
The self and social cognition
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Self-awareness
Moral reasoning
Theory of mind
Humor
Self awareness
• Craik et al. (1999): Self- vs.
other- reference (adjective
judgment): left medial
prefrontal
• Kelley et al. (2002): Eventrelated design; fMRI
– mPFC less deactivated than
control conditions
Moral Reasoning
• Moral decision
making task
• vs. categorical
judgements
• Frontal Polar
• Medial PFC
Moll, Oliveira-Souza & Eslinger, 2003
Mirror neuron system
Gallese et al., 2004
• Neurons in monkey ventral premotor cortex fire in
response to performance and observation of goal
directed action
• Human mirror-neuron network: inferior parietal, inferior
frontal
• Emotional states (pain. disgust): anterior insula
• Internal replication of others’ actions and emotions
– Links first- (“I do…”) and third-person (“She does….”) experience
• Direct understanding; may scaffold cognitive
representation
Emotion identification and empathy
• VPFC patients impaired on the identification of
facial expression
– not attributable to primary or secondary difficulties in
perception
– relates specifically to the emotional nature of the
stimuli
• Exhibited some combination of disinhibition or
socially inappropriate behaviour
• Reduction or absence of the ability to feel or
experience emotions
• Inability to empathize
Hornak, et al., 1996
Theory of mind:
Attribution of
mental states
• Understanding the
joke depends on the
ability to attribute
mental states to others
(left) or does not
(right)
• Contrasting: Medial
PFC
Theory of mind: Attribution of mental states
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PET: Fletcher et al (1995); Goel et al (1995): L MPFC
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Focal lesion: Happe (1999): R hemisphere stroke; Stone et al (1998):
ventral but not dorsolateral prefrontal
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Stuss et al. (2001): Transfer of inference: (visual perspective taking)
R PFC; Deception: ventral PFC
Non-Impaired
R
Impaired
Humor appreciation
Shammi & Stuss, 1999
Good luck on the exam!
Tuesday SF3202, 2-5pm
Answers:
Multiple choice:
Short answers:
“c”
“yes”
“executive functions”
“memory”
“emotion” or “affect” (1/2 credit)
Diagram:
Brain
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PSY393 Emotion and Self - University of Toronto Mississauga