Reward and Pleasure Flashcards
3 components of reward
liking (pleasure/hedonic component), wanting(motivation/drive), and learning
2 components of liking/pleasure component of reward
subconscious (bias) and conscious
2 dimensions of characterizing stimuli
intensity and valence (pleasantness)
relative intensities of positive and negative valence
negative valence is more intense
what are the 6 main brain hubs contributing to reward and pleasure
ventral pallidum, nucleus accumbens, orbitofrontal cortex, amygdala, thalamus, ventral tegmental area
where is the ventral pallidum
in the basal ganglia
where is the nucleus accumbens
in the ventral striatum (basal ganglia)
where is the VTA
midbrain; top of the brainstem
orbitofrontal cortex (OFC) role in reward/pleasure
involved in adaptive/reward based decision making
Mid anterior OFC function
represents sensory pleasure (positive valence stimuli)
Medial (middle) OFC function
learning and memory of rewards
lateral (outside) OFC
negative reinforcers (negative valence stimuli)
organization of reinforcers by complexity in the OFC
posterior: less complex reinforcers
anterior: more complex reinforcers
where is satiation signaling localized
orbital frontal cortex
how does OFC regulate/evolve adaptive decision making
-encodes valence
-maintains representations of expected rewards
-learns/updates reward expectations
-predict future rewards
-contributes to computation of decisions
endogenous opioids examples
endorphins, enkephalins, dynorphins
what are endogenous opioids used for
pain relief and reward
hedonic hotspot
area of the brain that responds to hedonic stimuli
effect of opioid agonist on nucleus accumbens
hedonic hotspot area: increased hedonic reactions
Adverse response area: decrease adverse response
Motivation area: increased motivation for stimuli
what do nucleus accumbens sites contribute to
dread and desirep
pathway of pleasure information to cortex
nucleus accumbens, ventral pallidum, thalamus, cortex
pathway of pleasure information to cortex: mechanism
mimics the direct pathway of basal ganglia; GABA increase from ventral pallidum -> inhibits thalamus
what does increased activity of ventral pallidum do
increase wanting/ motivation for stimuli
ventral tegmental area
structure in the midbrain that contributes to learning and reward prediction
positive reward prediction
not expecting reward, receives reward
negative reward prediction
expect reward, do not get reward
zero reward prediction
do not expect reward, do not get reward
where do ventral tegmental area cells release neurotransmitter (and which one?)
release dopamine to orbitofrontal cortex, nucleus accumbens, ventral pallidum
example of ventral tegmental area (VTA) and reward prediction
rate lever experiment; self stimulating via dopamine release
how do heroin and nicotine act on the brain
act on opiate and cholinergic (acetylcholine) receptors in VTA
how does cocaine act on brain
acts directly on receptors in nucleus accumbens cells and inhibits reuptake of dopamine/ amphetamines
what information do neurons in the amygdala encode
stimulus intensity and valence of stimulus
where and how does the amygdala send information
send to the orbitofrontal cortex via uncinate fasciculus
2 parts of the automatic nervous system
sympathetic nervous system (fight/flight) and parasympathetic nervous system (rest and digest)
cells that connect the ANS
autonomic ganglion
where does the ANS send information
smooth muscle
how is sensory information from reproductive organs sent though ANS
glans penis and clitorus send senory signals to spinal cord
neural mechanisms of sexual pleasure
HELP
pleasureable gloss
all different pleasure have the same baseline effect in the brain; key network of brain area involved with pleasure
why do all pleasures feel different
extra sensory experiences give rise to different effects that add to the pleasure the key brain areas provide to give the sensation of a particular pleasure
brain areas contributing to liking/ pleasure
mid anterior Orbitofrontal cortex, nucleus accumbens, ventral pallidum
brain areas contributing to wanting/motivation
nucleus accumbens, ventral pallidum, ventral tegmental area
brain areas contributing to reward based learning
medial orbitalfrontal cortex, ventral tegmental area, amygdala
what do endogenous opioids contribute to
liking/ pleasure
what does dopamine contribute to
wanting/motivation and reward based learning
where is the brains source of dopamine
ventral tegmental area
where is dopamine release in the pleasure/reward system
prefrontal cortex and nucleus accumbens
