Emotion Flashcards
What is an emotion?
Sometimes described as “affect” or “affective experience”
Many brain regions contribute to emotional experiences
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Many components:
» perception, expression, subjective feeling
» Associated actions, physiological changes, cognitive changes
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Emotions have survival value- adaptive emotional behaviour requires both rapid automatic responses and slower, elaborated responses
Subcortical contributions to emotion
Subcortical regions affect automatic aspects of emotion
The limbic system
> A collections of regions thought to contribute to emotion (both cortical and subcortical)
> Refers to the organization of these structures in a ring around the medial part of the brain
> Emotions depends on it, but which structures make up the system are still debated
Cortical contributions to emotion
Cortical regions affect slower, elaborative, and conscious assessments
Key structures involved with emotion (limbic system)
Anterior Cingulate Cortex
Nucleus accumbems
Hypothalamus
Orbitofrontal cortex
Amygdala
Hippocampus
The automatic Nervous system (ANS)
Fight-or-flight response
- Sympathetic branch of the ANS is important in bodily expressions of emotions, like changes in heart rate, respirations, sweating
Rest and digest response
- parasympathetic branch of the ANS activated under resting conditions
the HPA Axis
Hypothalamus, Pituitary gland, Adrenal glands
brain controls the body’s stress response through this
When stimulated by the hypothalamus, the pituitary gland secretes ACTH into the bloodstream (which stimulates the adrenal gland to produce cortisol)
Hypothalamus and Stressors
Governs the extent to which fight or flight is activated
controls the release of stress hormones w/ HPA axis
Receives input from the amygdala (which can modulate the fight-or-flight autonomic and stress responses
The Amygdala
Important for:
—- early detection of emotional information
—- rapid response to said information
—- learning emotional significance of information
Amygdala Complex (will be asked about!)
Amygdala consists of several nuclei
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Basolateral nuclei project to the hippocampus, prefrontal cortex, and regions involved in learning and memory
»» allows the amydala to influence LAM
Central nucleus and corticomedial nuclei connect to the hypothalamus
»» Enable emotional modulation of responses
Fear Conditioning
Form of classical conditioning (learning)
A neutral stimulus develops a negative emotional connotation through association with a negative stimulus
Damage to the amygdala disrupts fear conditioning in studies of animals and people w/ brain lesions
Effects of Amygdal damage in humans
—> loses ability to detect aversive emotional cue embedded in visual or auditory stimuli
—> inability to acquire fear conditioning
—> Inability to learn fear from verbal instruction, observational learning
Dual route model (amygdal connections)
- Low road pathway that projects directly from the anterior thalamus to the amygdala
—-> acts as a first alert - High road pathway that connect the sensory areas of the cortex to the amygdala
—-> Provides a more comprehensive context for processing emotional information
—-> Gives rise to a slower affective reaction that takes into account the complexity and details of the situation
Amygdala’s other connections
> > Bidirectional with the hippocampus
Projections from amygdala to cortex (like high road pathway)
——-> Enhance cortical processing of incoming sensory information based on emotional relevance
——-> May allow the amygdala to enhance attention to emotionally relevant information
Bidirectional with the visual cortex (fear response from vision)
Reward and Motivation
The brain signals which situations and actions lead to rewards
Nucleus accumbens is critical for supporting reward-related behaviour
Nucleus Accumbens
Critical for supporting reward-related behaviour
AKA ventral striatum
Receives dopamine projections from midbrain ventral tegnmental area
Closely connected to motor regions that support reward-seeking actions
Has two subregions
Nucleus Accumbens Subregions
The core: responsible for wanting, meaning of motivation to seek a desired goal
The shell is responsible for liking, the sensation of consummatory pleasure upon achieving a desired goal
Activation of Nucleus Accumbens
Activates:
> When a person recieves an unexpected reward
> When a person anticipates a predictable reward beore actually recieving it
> In response to a variety of different rewards (including addictive items)
Cortical contributions to emotion
Critical for:
Integrating emotion, decision-making, action
Inferring the feelings of others
Producing expressive emotional behaviour
Representing bodily cues of emotion
Regulating emotional responses
Interoception
The ability to perceive and represent one’s own internal body state (like recognizing your heart is beating fast
Appears to depend on the insular cortex (or insula)
Subdivisions of the insula
Posterior portion: connected to primary and secondary motor cortex and somatosensory cortex
—-> represents primary sensory information (like taste)
Anterior portions: connected to ACC (Anterior Cingulate Cortex)
—-> integrates sensory representations with awareness
Ventral Anterior Insula: connected to portions of ACC relevant to emotional processing
The Insula and disgust
Damage to the insula disrupts the experience of disgust AND the ability to recognize expressions of disgust in others
Activity in the anterior insula increases when a participant tastes bitter liquids, imagines disgusting scenarios, or sees another person expressing guilt
Some studies also associate the insula with feelings of guilt
Insula may have evolved to support taste sensations, but evolved to support disgust and guilt
Emotion and the Cingulate Cortex
The cingulate cortex is necessary for:
»» Action, cognition, emotion
» Evaluating the utility of actions that have emotional significance
» Intergrating motivational aspects of behaviour
Cingulate Cortex Zones
Posterior section (blue in slides)
»> motor functions
Middle section (red in slides)
»> cognitive control
Rostral/ Ventral section (green in slides)
»> emotion
The zones overlap in different sections (see slide 29 under emotion)
