Emotion and Motivation
Zara Melikyan, Ph.D.
Fall 2015
Lecture Plan
• Emotion and motivation: definition, theories
• Emotions and brain
– The limbic system
– The brainstem
– The cerebral cortex
– The autonomic nervous system
Definitions
Motivation – is a construct to explain behavior,
reasons for actions, desires, needs
– Cognitive component
– Emotional component
Motivation
– Inferred from goal-directed behavior
– Goal achievement usually associated with emotion
Definitions
Emotions - +/- reactions to situations
Emotional response:
– Feelings
– Physiological changes
– Behavior/urge to perform a behavior
Emotion, primary colors:
– Happiness, sadness, anger, surprise, disgust, fear
Function of emotion:
– Communicate motivational state
Theories of Emotion:
The James-Lange Theory
• Emotion = perception
of one’s physiological
changes in response
to a situation
• Physical sensations
evoke emotions
– We feel afraid
because we tremble
Criticisms of James-Lange Theory
• Incorrect assumption
– Each emotion has own set of physiological
changes
• Research
– Similar patterns of physiological arousal for
multiple emotions
Theories of Emotion:
Cannon-Bard Theory
• Psychological experience and & physiological
reactions are simultaneous
– Event
– Nerve impulses pass through thalamus
– Nerve impulses split in half:
• To cerebral cortex – Subjective experience of emotion
• To hypothalamus – Commands physiological changes
The Cannon-Bard Theory
Cerebral cortex
(Emotional labeling)
External
Stimulus
Thalamus
Emotion
Hypothalamus
(Physiological
response)
8
Criticisms of the Cannon-Bart Theory
• Incorrect physiology
– Thalamus is not the center of emotional
experience
– Emotion is a function of circuitry, not “centers”
Theories of Emotion:
The Papez Circuit
Three proposed circuits:
• Stream of feeling
– Limbic system
• Stream of movement
– Sensations through thalamus to basal ganglia
• Stream of thought
– Sensations through thalamus to cerebral cortex
Emotion – merging of streams
Emotional responses
• Behavioral
– Muscular movements: facial expression, entire body
movements
• Autonomic
– Quick mobilization, facilitates behaviors.
Sympathetic/parasympathetic NS
• Hormonal
– Reinforce autonomic responses: adrenal medulla
secretes EP, NE, steroid hormones
The Limbic System
• Thalamus
– Sensory information specific nuclei
• Hypothalamus
– Changes in autonomic nervous system (e.g. heart rate)
associated with emotion
The Limbic System
• Amygdala
– Fear and aggression
– Facial emotion recognition
(esp. negative)
– Emotional memory
• Hippocampus
– Memory (esp. emotional
memory)
The Brainstem
• Pons
–
–
–
–
–
–
•
Locus coeruleus
Secretes NE
Experiencing pleasure
Triggers emotional arousal
Too little – depression
Too much over a long period of
time – severe stress
Midbrain
–
–
–
Substantia nigra
DA
Pleasurable sensations
The Cerebral Cortex
• Temporal lobes
– Emotional memory
• Frontal lobe (esp. prefrontal cortex)
– Inhibition
– Regulating emotions produced by amygdala
The Autonomic Nervous System
• Sympathetic nervous system
– “Fight or flight” response
• Parasympathetic nervous system
– Energy conservation
In threatening situation ANS responds within
seconds
– Physical reaction including reflexes
– Emotional reaction
Cognition and Emotion:
Schacter’s Two-Factor Theory
• Physiological arousal
• Cognitive evaluation based on environmental
cues
Fear
Amygdala
• Organizes responses to aversive stimuli
• Integrates behavioral, autonomic, and hormonal responses
• Has reach connections with cortical and subcortical structures
Central nucleus – emotional responses to aversive stimuli
– Destruction of SN – no fear, stimulation – fear
– Particular stimuli: loud, big; or learned/conditioned S evoke fear response
Basal nucleus
Lateral nucleus – physical changes related to response; behavioral,
autonomic, hormonal responses
Inhibition of conditioned fear response – Ventromedial prefrontal cortex
Amygdala damage impairs memorization, perception of “-” emotional stimuli
Anger, Aggression, Impulse Control
Aggressive behavior
– Attacks
– Threat behaviors
Threatened demonstrates:
–
–
Defensive behavior
Submissive behavior
Sympathetic system is more activated in pray then predator
Aggressive behavior
– Muscular movements – brain stem
– Brain stem is controlled by hypothalamus and amygdala
– Limbic system is controlled by perceptual system, cortex
Anger, Aggression, Impulse Control
SE inhibits aggression, controls risky behavior
Low levels associated with antisocial behaviors, assault
SE agonists (e.g. Prozac) decrease irritability, aggressiveness
Human violence and aggression is serious problem
Hereditary factor in antisocial behavior and aggression
Ventromedial prefrontal cortex
–
–
–
–
Inhibits reactions, including aggression
Emotional dysregulation, impulsive violence
Phineas Gage destroyed vmPFC bilaterally
Decreased prefrontal activation, increased subcortical (amygdala)
activation in murderers with negative emotions vs. cold-blooded
– SE influences on prefrontal cortex
Hormonal Control of Aggressive
Behavior
• Males are more aggressive than females
• Male aggressiveness is better tolerated in
society
• Androgen stimulates testosterone-sensitive
neural circuits that facilitate aggression
Communication of Emotions
How we feel and what we are likely to do, by:
• Postures, movements
• Facial expression
• Speech and non-verbal sounds
Facial emotional expressions use spices-typical repertoire (cross-cultural
studies, blind people) (C. Darwin and others)
Facial emotions recognition:
• Fast, automatic, accurate
• Visual and auditory systems
• Right hemisphere is more involved
• Amygdala involved in emotional perception (face and body), especially “-”
emotions
• Imagining/imitating observed emotions, mirror neurons of parietal lobe
Neural Basis of Emotional
Communication
• Volitional facial paresis
– Damage to primary motor cortex, motor nucleus of facial
nerve
– Can not voluntarily move facial muscles, but can express
genuine emotions
• Emotional facial paresis
– Damage to the insula of prefrontal cortex, frontal lobe,
thalamus
– Can move facial muscles, but can not express emotions on
the affected side of the face
• Understanding jokes and reacting to them –
ventromedial prefrontal cortex