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Emotion and Cognition
• Historically emotion and cognition were
thought to be distinct and separable mental
activities
• E.g., Plato proposed that the mind had 3
separable aspects: intellect, will, and emotion
Emotion and Cognition
• What is emotion
– Controversial question
• Emotions are (Ochsner & Gross Handbook of
emotions)
– 1. Valenced (i.e., good/bad) response to external
stimulus or internal representation that involves
– 2. result in changes across multiple types of
responses (behavioral, physiological)
Emotion and Cognition
• Emotions
– 3. often have identifiable triggers
– 4. both learned (response to a bully) and
unlearned (withdrawing hand from hot stove)
– 5. mediated by distinct neural systems
Emotion and Cognition
• Recent focus on emotion comes from
cognitive neuroscience research, which
demonstrated that there are specific neural
structures (esp. Amygdala), that are
specialized for processing emotional stimuli
Emotion and Cognition
• Emotions
– Case of S.M. (damage to amygdala)
– S.M. age 42
– Last time S.M. appear to be scared was at the
age of 10 although she has been physically
assaulted and held up at knife point
– S.M. has Urbach-Wiethe disease a genetic
disorder that is progressive
– Leads to degeneration of amygdalae
Emotion and Cognition
• S.M.
– Neuropsychological tests
– S.M. intelligence in normal range
– No perceptual or motor problems
Emotion and Cognition
• S.M. performance on tests of emotion
– Impaired in fear identification in set of photos;
normal performance on sadness, anger, disgust,
happiness, and surprise
– Could sketch facial diagrams showing each
emotion above except for fear
Emotion and Cognition
• S.M. performance on tests of emotion
– Studies showed that she understands situations
that are fearful
– But, this does not appear to prevent her from
getting involved in fearful situations
Emotion and Cognition
– Amygdala - small almond-shaped structure, just
anterior to the hippocampus; it is located in
medial temporal lobe
– Amygdala is specialized in processing emotion
– Amygdala also influences cognitive processes
and is influenced by cognitive processes
• Thus, both cognition and emotion need to
considered in context of each other
Emotion and Cognition
• Amygdala and related
brain structures
Emotion and Cognition
– Basic question: are emotions biologically
hardwired or derived from other more basic
causes
– William James argued they were derived or
assembled from more basic causes
– Charles Darwin argued that certain emotions
were hardwired
Emotion and Cognition
– Darwin (1873) The expression of emotion in man
and animals
– Investigated emotion across cultures and argued
that the expression of certain emotions through
facial expression was the same across cultures
– Eckman (1960) investigated cultures around the
world and discovered that facial expression for
the following emotions was the same: anger,
fear, disgust, sadness, happiness, surprise
Emotion and Cognition
– Conclusion: this suggests that these emotions
are innate and that they may be elicited by the
same brain mechanisms across people
Emotion and Cognition
– Analyzing emotions
– 1. Basic emotions: relatively small set of
emotions developed through evolution, and
reflected in facial emotion (e.g., fear, anger,
happiness)
– 2. Complex emotions: combinations of basic
emotions (e.g., satisfaction); often learned
socially
Emotion and Cognition
– Analyzing emotions
– 3. Dimensions of emotions: emotions can be
assessed in terms of
Valence (pleasant - unpleasant; positive - negative)
Arousal – assesses the amount of valence
Phineus Gage
Phineus Gage
• Computer
reconstruction of the
path taken by tamping
iron through skull of
Phineus Gage
Emotion and cognition
• Gage walked away from accident, could describe the
accident the next day, and within a month was deemed able
to resume work as a foreman
• It became clear that Gage was “no longer Gage”
• Prior to injury Gage was a sober, responsible, intelligent, home body,
with no peculiar or bad habits; he was a responsible, valued
employee
• After injury he was erratic, given to grossest profanity, impatient,
unwilling to listen to advice, and unable to plan effectively
• Tamping iron damaged medial region of prefrontal cortex
• Subsequent research has shown that damage to frontal
lobes can lead to dramatic changes in personality while
keeping perception, consciousness, and most cognitive
functions intact
Emotion and cognition
• Neural circuits of emotion
– Emotion is believed to be multifactorial and to involve
several circuits
– several different types of emotional behaviors exist and
their expression depends upon the specific nature of the
task
– several different brain regions are involved in emotion
– These include the anterior cingulate, hypothalamus, and
basal ganglia
– 2 regions primarily involved in emotion are the
amygdala and the orbitofrontal cortex
Emotion and cognition
• Orbitofrontal cortex
– Forms the base of the prefrontal cortex and is adjacent to
the upper wall of the orbit above the eyes
– Orbitofrontal cortex is broken down into two distinct
areas: the ventromedial prefrontal cortex and the lateral
orbitofrontal prefrontal cortex
ventromedial prefrontal cortex – is one of the primary areas
damaged in Phineus Gage
– Exact function of orbitofrontal cortex is unclear, but it
appears to be involved in regulating our ability to inhibit,
evaluate, and act in social and emotional decision
making situations
Emotion and cognition
• Human orbitofrontal
cortex, divided into the
lateral orbitofrontal
cortex (green) and the
ventromedial prefrontal
cortex (red)
Emotion and cognition
• Human orbitofrontal
cortex
Emotion and cognition
• Emotional learning
– places, persons, locations, and objects have an emotional
valence or value associated with them
– Valence is usually acquired through emotional learning
– Some stimuli are inherently positive or negative; no
learning is involved – e.g., shock, very loud noise; these
are referred to as primary reinforcers
– Other stimuli are neutral initially but take on a positive or
negative valence because they have positive or negative
consequences associated with them; i.e., the emotional
valence is learned; called secondary reinforcers
Emotion and cognition
• Fear conditioning
– Fear conditioning used to investigate emotional learning
of negative valences
– Paradigm with rats
– An initially neutral stimulus (CS conditioned stimulus)
such as a light is paired with an aversive stimulus such as
a mild shock (US unconditioned stimulus)
– Shock elicits a fear response to shock, called an
unconditioned response
– With repeated trials the rat learns that the light predicts
the shock and exhibits a fear response to light, called the
conditioned response
Emotion and cognition
• Fear conditioning
– Results show that damage to the amygdala impairs
conditioned fear responses
– However, damage to the amygdala does not impair the
fear response indicating that response does not depend
upon the amygdala
– Thus amygdala is associated with learning or memory of
fear
– The neural circuit associated with fear learning is complex
Emotion and cognition
• Fear conditioning
– Neural circuit associated with fear learning
– Emotional stimulus (e.g., CS light) seen by eyes; projects
to thalamus; then sent (a) to amygdala “low road”; and (b)
to sensory cortex (e.g., visual cortex) “high road” for
further analysis
– The “low road” provides quick and dirty crude signal to
amygdala that a stimulus resembling the CS was
perceived; high road provides a more detailed analysis of
sensory input, which then, if it is CS, is projected back to
the amygdala
Emotion and cognition
• Fear conditioning
– Neural circuit associated with fear learning
– Thus, there are 2 routes of projection to the amygdala; a
fast signal that is susceptible to error and a slower route
that less error prone
– Advantageous when a danger is present to have dual
routes
– Information from amygdala projects to regions that
activate behavioral, autonomic, and endocrine (hormone)
emotional responses
– It also projects to anterior cingulate and ventromedial
frontal lobe
Emotion and cognition
• Emotional processing by
human to rattlesnake
• Note: “high and low road”
routes to amygdala;
autonomic responses
(e.g., heart rate); actions
of hiker modulated by
ventromedial frontal
regions
Emotion and cognition
• Emotional learning and memory
• Neural circuit associated with fear conditioning is believed to
be an implicit memory system; its effects are expressed
indirectly through a behavioral or physiological response
though of course humans can directly express the response
– However, many emotional memories are believed to be
implicit and explicit and are mediated by different brain
regions
Emotion and cognition
• Emotional learning and memory
• Neural circuit associated with fear learning and memory
– Phelps (1998) Patient SP had bilateral amygdala damage
– Fear conditioning experiment
– SP and controls were presented a blue square and during
acquisition phase of study, the blue square was paired
with a mild electrical shock to the wrist
– SP and controls showed normal fear response to shock
as measured by skin conductance response (SCR), an
autonomic nervous system response indicating arousal
– However, SP did not show a conditioned response to the
conditioned stimulus (blue square) presented by itself
Emotion and cognition
• Aside
• Emotion elicits bodily reactions
– when scared, heart beats faster and we sweat as
a result of arousal of the autonomic nervous
system
– Skin conductance response (SCR) also called
galvanic skin response (GSR) measures change
in skin conductance resulting from activity of
sweat glands; hence a measure of arousal
Emotion and cognition
• Skin conductance
response by SP and
controls to conditioned
and unconditioned
stimulus
Emotion and cognition
• Emotional learning and memory
• Neural circuit associated with fear learning and memory
SP however, had declarative memory for the experimental
task and reported that she understood the association
between the blue square and the electrical shock, and
anticipated being shocked when shown the blue square
Using the same experimental paradigm, patients with
hippocampal damage and intact amygdala showed the
opposite pattern of results – i.e., normal autonomic
conditioning, but were unable to report there was a blue
square, or the association between the blue square and
electrical shock
Conclusion- amygdala necessary for implicit expression of
emotional learning, but not necessary for explicit memory
emotional events
Emotion and cognition
• Social decision making
– Frontal lobes are positioned to combine information from
a variety of sources because of way information from the
posterior regions projects to the frontal regions
– Thus, it can select what behavior is appropriate in a given
situation
– The orbitofrontal lobes appear to help in the selection of
appropriate actions when action is based on social cues
– Patients with orbitofrontal lobe damage appear to have
difficulty taking into account social context in their actions
relying too heavily on perceptual cues, and producing
inappropriate responses in a social context
Emotion and cognition
• Social decision making
– In terms of Shallice’s SAS model, the perceptual input is
not combined with contextual information to select an
appropriate response
Supervisory
Attentional
System
Perceptual
Structures
Trigger
Data
Base
Effector
System
Contention
Scheduling
Emotion and cognition
• Social decision making
– Utilization and imitative behavior
– Lhermitte (1983; 1986) showed that px with frontal lobe
damage tended to rely excessively on perceptual input
and show imitative and utilization behavior
– E.g., px pick up pencil on doctor’s table, and perform
actions that were socially odd – e.g., came in doctor’s
office where there was a hammer, nail, and picture and
began to hang the picture
– Or socially inappropriate – left hypodermic needle in
desk, doctor dropped his trousers, and turned his back on
patient– patient pick up needle and jabbed it into doctor’s
butt! (Don’t try to get this through ethics)
– Lhermitte dubbed this utilization behavior -- patient’s rely
too much on perceptual input to guide behavior
Emotion and Cognition
• Imitative and utilization
behaviors
• Imitation. Patient
mimics physician
making threatening
gesture
Emotion and cognition
• Utilization behavior
patient – when objects
are placed in front of
patient, he or she uses
them – Patient tries to
put on 3 pairs of
glasses
Emotion and cognition
• Emotional decision making
– Damasio (1994) argued that rational decision making
depends critically on an emotional evaluation of the
consequences of an action
– When weighing the consequences of an action we need
to have an common measuring stick to assess the
benefits and costs of an action
– This metric was called by Damasio, a somatic marker
– Somatic markers are bodily sensations (gut feelings) that
help us evaluate our feelings about a potential action
– Quick process that allows us to assess which options we
feel most positively about, and they allow us to discard
options that elicit negative feelings
Emotion and cognition
• Emotional decision making
– Test of somatic marker hypothesis (Damasio, 1994)
– Provides an account of behavior of px with orbitofrontal
(and perhaps amygdala) damage
– Such patients understand events and objects that are
emotionally affective, but they are stripped of emotional
content (valence) associated with them
– Skin conductance response (SCR) experiment
– Purpose: to determine whether orbitofrontal px have
normal SCR to pictures with emotional content
– Note: these pictures have content by virtue of our
memories; they are not intrinsically arousing like a loud
noise or electrical shock
Emotion and cognition
• Emotional decision making
– Test of somatic marker hypothesis (Damasio, 1994)
– Px with orbitofrontal damage and controls were
shown a series of emotional and neutral photos;
SCR was measured
– Results showed that px with orbitofrontal damage
did not show autonomic emotional response to
emotional stimuli, unlike controls
– However, both groups showed an autonomic
response to an intrinsically negative stimulus like
a loud noise
• 13.8 Top panel shows
examples of neutral (N)
and Emotional (E)
stimuli used in
experiment
• Bottom panel shows
SCR responses of
patients and controls
Emotion and cognition
• Emotion and declarative memory
– Consolidation refers to a process by which memories
become more stable over time, and in some cases
performance on tasks requiring memory improves
– In the case of declarative memories for emotional events
this process appears to take time and occurs through the
modulation of hippocampal processing during storage
not encoding
Emotion and cognition
• Emotion and declarative memory
– Experimental approach to investigate effects of amygdala
activation on declarative memory
 Investigators disrupted or enhanced amygdala processing
after memory encoding
 E.g., Study – maze learning task with rats (maze learning
requires hippocampus); after learning rats were given drug
that induced excitation response in amygdala or saline
(baseline) injection
 Group with elevated amygdala response showed better
memory for the maze than baseline group (Packard &
Teather, 1998)
Emotion and cognition
• Emotion and declarative memory
Effects of amygdala activation have also been reported for
nondeclarative (habit memory) memory mediated by the
striatal regions (Packard & Cahill, 2001)
Emotion and cognition
• Emotion and declarative memory
– Experimental approach to investigate effects of amygdala
activation on declarative memory
 Amygdala enhances hippocampal consolidation through
activation of the beta-adrenergic system in the amygdala (a
system that is hormonal activated); it has been shown that beta
blockers that block beta-adrenergic receptors also eliminate the
effects of arousal on memory
 Note: the hormonal changes that affect hippocampal
consolidation are released during emotional arousal in situations
of danger.
– it has been proposed that functional purpose of this
process is to increase chances that stimuli that result in
an emotional reaction are more likely to be not forgotten
Emotion and cognition
• Emotion and declarative memory
– Declarative memory is better for emotional arousing
stimuli
– Amygdala has a secondary role in declarative memory
(although a primary role in nondeclarative emotional
memory)
– Px with amygdala damage did not show an arousalenhanced memory (e.g., La Bar & Phelps, 1998)
– Also there was a correlation between strength of an
amygdala response to an emotional stimulus at encoding
and subsequent memory performance as measured in a
neuroimaging study (e.g., Cahill et al., 1996)
– Thus amygdala influences declarative memory but medial
temporal lobe is critically involved in acquisition of
declarative memories
Emotion and cognition
• Emotion and declarative memory
– Experimental approach to investigate effects of amygdala
activation on declarative memory
– Effects of delay on emotional memory
– If arousal affects storage of declarative memories via the
amygdala, then there should be slower forgetting of
emotional than neutral stimuli
– Kleinsmith & Kaplan (1963) presented word-digit pairs at
study; half the words were emotional and arousing; half
were neutral
– At test, words were presented and participants recalled
the digits; participants were tested immediately or after 24
hours
Emotion and cognition
• Emotion and declarative memory
– Kleinsmith & Kaplan (1963)
– Results
– On immediate test there was no difference between
neutral and emotional words
– At 24 hour delay digits paired with emotional words were
better recalled
Emotion and Cognition
• Kleinsmith & Kaplan (1963)
• Recall of digits paired
with emotional or
neutral words on
immediate test or after
24 hour delay
Case Description of AM
 Successful businessman prior to TBI
 Average to very superior general intellectual
functioning
 Normal academic, attention, and executive
function abilities
 Generally intact memory abilities
 Poor social judgment; everything is positive
Park et al. (2001) Neuropsychologia
Neuropsychology of semantic
memory
• How are other types of information
represented in semantic memory?
– Some evidence suggests that evaluative
information is processed and stored in a different
location than denotative information
R. Temporal
Temporal
a
L. Amygdala
b
Amygdala
Frontal
c
d
Attitude Priming Study of AM
 Purpose: to investigate AM’s evaluative rating
of words
 Hypothesis: impaired automatic evaluation of
negative but not positive evaluative stimuli
Park et al. (2001) Neuropsychologia
Attitude Priming (continued)
 Method: attitude priming paradigm
– Participants: AM and 8 age - and education matched controls
 Procedure:
– Phase 1: rate single words as “good” or “bad”
– hypothesized positivity bias
Park et al. (2001) Neuropsychologia
Rating of Words in Phase 1
Number Rated "Good"
80
70
60
50
Controls
AM
40
30
20
10
0
Controls
AM
Response Latency to Phase 1
Words
3000
2500
Msec
2000
Negative
Positive
1500
1000
500
0
AM
Control
Phase 2
prime
(pos or neg)
250 ms
blank
screen
50 ms
target
(pos or neg)
Task: rate target as good or bad as quickly as possible
Control Priming Results Phase 2
800
Msec
760
Pos. Prime
Neg. Prime
720
680
640
Positive Target
Negative Target
AM Priming Results Phase 2
4000
3500
Msec
3000
2500
Pos. Prime
Neg. Prime
2000
1500
1000
500
0
Positive Target
Negative Target
Summary of Attitude Priming
 Positivity bias in rating single words
 Slowed responses only to words rated as bad
 Priming in positive valence condition only
 Conclusion: AM can automatically access
positive but not negative evaluative
information
Park et al. (2001) Neuropsychologia
Connotation Generation Study of AM
 Purpose: to determine whether AM could
access negative evaluative information when
directed
 Task: describe two positive and two negative
features of single words (e.g., coffee)
 Same 92 words used as primes in
Experiment 1
Park et al. (2001) Neuropsychologia
Acceptable Good and Bad
Connotations
Acceptable Connotations
0.9
0.8
0.7
0.6
0.5
Good
Bad
0.4
0.3
0.2
0.1
0
AM
Control
Semantic priming and AM
• Purpose of experiment
– to determine whether AM would show normal
semantic priming
– prior research has shown that the latency to
respond to a target is facilitated when the prime
preceding the target is semantically related
compared to when it is unrelated
• Method
– similar to Phase 2 of the first study
Semantic priming and AM
• Method
– similar to Phase 2 of the first study
– task: show prime-then target; make a lexical
decision about target item (word/nonword)
Semantic priming and AM
Mean response latency
(ms)
Mean response latency (ms) to semantically related
and unrelated word pairs
1000
900
800
700
600
500
400
300
Related
Unrelated
AM
Control
Conclusions
• Conclusions
– AM impaired in his automatic processing of
negative evaluative information
positivity bias
no priming for negative evaluative words
– AM not impaired in his denotative or semantic
processing of words
– suggests a dissociation between these two
aspects of semantic memory