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Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
Chapter 13 Emotion
“For Charles Darwin, it was obvious beyond any need for argument that non-human animals are
sentient ‘… the lower animals, like man’ he wrote in1871, ‘manifestly feel pleasure and pain,
happiness and misery’.’ The fact that the lower animals are excited by the same emotions as
ourselves is so well established that it will not be necessary to weary the reader by many details’.
However, in the belief that identifying problems and finding ways to answer them is a way to move
forwards, I shall first emphasize why sentience is still a profound problem, despite the ease with which
Darwin spoke about the mental experiences of animals.”
Marian Stamp Dawkins, 2006
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
Chapter Outline
1.0 Introduction
2.0 Panksepp’s emotional brain system
3.0 The FEAR system
4.0 The SEAKING system
5.0 Summary
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
1.0 Introduction
The emotion systems of the brain and their
interactions with cognitive processing
Do you remember where you were on
September 11, 2001?
You likely do recall that day. And just as
likely, you do not recall what you were doing
on September 10th, 2001.
The events of 9/11 are firmly etched in our
brains because of the highly charged
emotions that are entwined with the memory
of the occurrences of that day.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
1.0 Introduction
The triune brain
Paul MacLean introduced the ‘triune brain’
concept in1990 to describe the functionally
distinct layers of the mammalian brain. It has
become a widely-used way of thinking about
the overall functional organization of the
brain.
In MacLean’s view, the brain developed over
the course of vertebrate evolution into a
three-layered organ, where these layers
retain of the separateness of their different
evolutionary origins despite being highly
interconnected.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
1.0 Introduction
The triune brain
The oldest layer of the brain is called the
reptilian brain, composed of the
brainstem -- the structures that dominate
in the brains of snakes and lizards.
The mammalian brain is layered over the
reptilian brain, it consists primarily of a
system of brain parts called the limbic
system, sometimes referred to as the
Papez circuit. The limbic system plays a
major role in human emotion.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
1.0 Introduction
The triune brain
The neocortex or primate brain is the
most recent addition to our brain. It
consists of a wrinkled covering of the
cerebral hemisphere which has
mushroomed in primates and humans as
compared to other mammals.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
1.0 Introduction
Basic emotions and the role of the reflective consciousness
Emotional responsiveness is governed by:
Classically conditioned responses to stimuli that previously brought pleasure or
created pain mediated by subcortical systems
and
Cognitive appraisals of stimuli in context mediated by the neocortex
Neuroscientists have given most attention to the classical conditioning studies
conducted with animal models. Almost no attention has been given to the possibility of
multiple emotional systems in the brain. Affective neuroscientists have begun to think
of mammalian emotion as arising from several separate genetically-determined
networks of brain areas, each serving an adaptive function.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
2.0 Panksepp’s Emotional Brain System
Panksepp (1998) offered a functional definition of an emotional system in the brain,
identifying functions ranging from unconditional sensory inputs to emotion control
over cognition.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
2.0 Panksepp’s Emotional Brain System
Panksepp described a set of 4 fundamental
‘hard-wired’ emotion systems found in
mammalian brains:
SEEKING
forward locomotion, sniffing, investigating
FEAR
freezing, fright, escape
RAGE
attack, biting, fighting
PANIC
agitation, distress vocalization
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
2.0 Panksepp’s Emotional Brain System
Panksepp described excitatory and inhibitory influences -- such as an excitatory
relationship between FEAR and RAGE -- among the 4 systems as well as three
other special-purpose systems: LUST, CARE, and PLAY.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
2.0 Panksepp’s Emotional Brain System
The feelings of emotion cannot be studied in nonhuman mammals, although we can make some
guesses about the felt experiences of other mammals
by observing their behaviors.
Emotional feelings can be investigated in humans: a
PET study investigated brain responses when subjects
self-generated emotions such as happiness, sadness,
fear, and anger.
They noted different neural maps for the differing
emotions both in cortical and subcortical areas. Right
panel shows brain areas active for happiness (top) and
anger (bottom) (Damasio et al., 2000).
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Afferent pathways to the amygdala
The FEAR system is a neural
system for avoiding pain or
injury. The system responds to
both unconditional stimuli (loud
sounds, sudden movements,
painful stimuli, fearful faces) and
conditioned stimuli (classically
conditioned danger signals,
memories).
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Afferent pathways to the amygdala
Emotion-relevant information arrives at the
amygdala via 4 afferent pathways:
Olfactory information: from the olfactory
cortex
Visceral information: from the
hypothalamus and septal area
Affect-relevant information about internal
states: from the hypothalamus, brainstem,
orbital cortex, and anterior cingulate
cortex
Sensory information: from temporal lobe
structures
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Efferent pathways from the amygdala
Efferent pathways from the amygdala
mirror the afferent paths, returning
signals to subcortical locations and to
the brainstem. There are also direct
efferent pathways to entorhinal cortex,
inferior temporal cortex, and to visual
cortex, including the fusiform face area.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Conscious and unconscious fear processing: LeDoux’s Low Road and High Road
LeDoux labeled the two sensory
input pathways to the amygdala for
perception of fearful stimuli the ‘Low
Road’ and the ‘High Road’.
The Low Road is a fast pathway from
sensory receptor to thalamus to the
amygdala that bypasses the cortex.
It enables rapid, automatic,
unconscious reactions to the broad
outlines of potentially dangerous
stimuli.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Conscious and unconscious fear processing: LeDoux’s Low Road and High Road
The longer thalamo-corticoamygdala ‘High Road’ pathway takes
somewhat longer to traverse but
allows complex, contextualized
processing of stimuli followed by
conscious, deliberate responding.
The High Road is influenced by
social and personal decision making
processes and can reflect culturespecific emotional responses.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Fear without awareness: do we need conscious awareness in order to process
emotional stimuli?
Vuilleumeir and colleagues investigated this
question with a patient with right parietal neglect
and visual extinction due to damage in his right
inferior parietal cortex (see white arrows).
If visual stimuli were presented to just one visual
field, he had no difficulty perceiving them.
However when shown two different stimuli
simultaneously in right and left visual fields, he
would report not being able to see the stimulus
presented to his left visual field -- the ‘neglected’
visual field.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Fear without awareness
Unilateral Condition: the patient was able to see the stimuli presented to just the right
or just the left visual field 100% of the time.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Fear without awareness
Bilateral Condition: the patient reported being unable to see the faces (projected to his
left visual field and on to his damaged right cortex) about 65% of the time. The
important finding was that fearful faces activated the amygdala whether they were
reported as seen or not -- thus without conscious awareness.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Cognition-emotion interactions: FEAR
What is the role of the amygdala in cognitive-emotion interactions?
Converging evidence from animal and human studies indicate five areas of cognitiveemotion interactions involving the amgydala:
•Implicit emotional learning and memory
•Emotional modulation of explicit memory
•Emotional influences on perception and attention
•Emotion and social behavior
•Emotion inhibition and regulation
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Emotional modulation of explicit memory
Psychological evidence has been available for
some time indicating that moderate levels of
emotional arousal (most often fear-based
arousal) at the time of an event lead to better
retention of explicit memories.
Pathways include the adrenaline (green) and
the cortisol (pink) pathways. Note that both
pathways begin in the amygdala, circulate to
the adrenal gland, and feedback to the
amygdala and hippocampus after passing
through the body.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Emotional influences on perception and attention: the Emotional Stroop Test
The action of the amygdala can make cortical areas momentarily more receptive to
certain adaptively important stimuli. An example of this greater receptivity is found in
the Stroop test. Results from Vietnam War veterans show that words that have
personal significance (‘bodybag’) are found to gain access to awareness more readily
than neutral words, resulting in longer delay in naming their ink color.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Emotion and social behavior
Faces -- and eyes -- contain vast
amounts of emotionally significant
information. The amygdala has
been shown to respond to wideopen eyes of fearful and surprised
expressions. But what about just the
whites of the eyes?
A study by Whalen and colleagues
(2004) showed that the amygdala
was selectively activated in
response to subliminally presented
fearful vs. happy eye-whites.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
3.0 The FEAR System
Emotion inhibition and regulation
Fear learning is long lasting and
stable, remarkably resistant to
change and voluntary control.
Research on processes underlying
the inhibition of learned fear
responses is important, especially
for individuals who have
experienced traumatic events.
Emotional responsiveness can be
regulated to some extent by topdown influences from cortex to
amygdala.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
4.0 The SEEKING System
Panksepp described the SEEKING
system as the appetitive system that
makes mammals curious about their
world and promotes goal-directed
behavior toward a variety of goals
objects, such as food, shelter, sex.
This concept of the SEEKING system
includes classical reward pathways in
the brainstem as well as in other
subcortical areas.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
4.0 The SEEKING System
In contrast to the FEAR system which
gives rise to freezing, hiding, or flight in
service of self protection when activated,
the SEEKING system is a positivelyvalenced, energizing system that moves
animals out into their environment to
forage and experience.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
4.0 The SEEKING System
The primary reward pathways in
mammals include the:
Mesolimbic dopamine pathway:
dopaminergic neurons that originate in
the ventral tegmental area (VTA) of the
brainstem terminate at the nucleus
accumbens in the forebrain
Mesocortical dopamine pathway:
dopaminergic neurons project from VTA
to orbitofrontal cortex
VTA is located inside the pons in the
midbrain, the nucleus accumbens is
located anterior to the amygdala.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
4.0 The SEEKING System
Re-interpreting ‘reward’: from reward to reward
prediction to reward prediction error
For a long time, the dopamine system was thought to
respond at receipt of rewarding stimuli. More recent
work has provided evidence that neurons in this
system are more responsive to anticipation of reward
than receipt of reward.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
4.0 The SEEKING System
Re-interpreting ‘reward’: from reward to reward
prediction to reward prediction error
An example of an individual dopamine neuron that is
inhibited by by a stimulus predicting reward omission:
A+: Stimulus A is paired with reward A+ and excites
the dopamine neuron
AX-: Stimulus A is presented with X with no reward
therefore X predicts reward omission
X-: When X is presented alone, the dopamine neuron
is inhibited
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
4.0 The SEEKING System
Reward is more than learning
While learning to anticipate a reward is an important aspect of the
SEEKING system, other hedonic aspects are also key: liking reactions are
neurally modulated by a distributed brain network (shown in green); neural
pathways for wanting (shown in yellow) are separable from liking.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
4.0 The SEEKING System
Reward is more than learning
Facial expressions for
liking reactions are similar
in human infants, juvenile
orangutans, and adult rat.
Disliking reactions are
also similar across
species.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
4.0 The SEEKING System
‘Reward pathway’ and drug use
All drugs of abuse have their effects
on the wanting system via the
dopamine pathways and their
connections in the midbrain.
Natural rewards indirectly affect the
reward system by decreasing the
action of inhibitory interneurons that
normally inhibit the dopaminergic
neurons of the VTA, resulting in
increased activity in dopaminergic
neurons in the VTA.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
4.0 The SEEKING System
‘Reward pathway’ and drug use
In contrast, cocaine and
amphetamine act directly on the
nucleus accumbens to maintain high
levels of dopamine at synapses of
dopaminergic neurons in the
mesolimbic dopamine system.
Cognition, Brain and Consciousness: An Introduction to Cognitive Neuroscience
Edited by Bernard J. Baars and Nicole M. Gage
2007 Academic Press
5.0 Summary
Mammals have separate emotional systems in the brain, each with patterned, innate
responses to stimuli in the expected environment of the species related to survival.
Systems such as the FEAR system and the SEAKING system have both conditioned
and unconditioned responses to stimuli supported by separate neural networks: FEAR
relies on the amygdala and its connections, SEAKING relies heavily on the
mesolimbic and mesocortical pathways of the VTA.
Each of these systems can come under cognitive control and reciprocally influence
higher decision-making, appraisal systems, and consciousness.
Each system is capable of elaborating distinctly different subjective feelings.