Unit 3 Neuroscience of Pain and Reward Flashcards
What is psychological hedonism?
Perspective arguing that people are motivated to act in ways that increase pleasure & decrease pain
Define reward vs pleasure, primary vs secondary reward, punishment vs pain, primary vs secondary punishment.
Reward: something an animal will work to achieve
Pleasure: what is feels like to engage with said reward
Primary reward: naturally rewarding and biologically essential –> do not have to learn to appreciate them.
Secondary reward: Learned rewards that gain importance through repeated associations with primary rewards (i.e. money)
Punishment: Something an animal will work to avoid
Pain: the subjective hedonic and motivational response to punishing stimuli (experience of discomfort)
Primary punishment: naturally aversive, threaten survival
Secondary punishments : learned punishments that acquire aversiveness through repeated associations with primary punishments (e.g., financial loss, bad grades)
What is subjective utility
Personal value or satisfaction an individual assigns to an outcome based on their preferences and
circumstances –> depends on internal and external context
What is alliesthesia?
Subjective hedonic value of stimulus is tied to extent to which a stimulus
contributes to or disrupts homeostasis –> i.e. food is more pleasurable when hungry and not pleasant when full.
What are the two components of pain? Which brain regions are associated with these two components?
Sensory-discriminative component: provides information about intensity, quality, and location
-Associated with the primary and secondary somatosensory cortices and posterior insula
Affective-motivational component: relates to emotional experience of the pain (how distressing is it?) & drives motivation to escape or stop painful experience
-Associated with the dorsal anterior cingulate cortex (dACC) and the anterior insula (AI)
Why is pain adaptive?
- Allows us to take appropriate action and pay attention to something that could cause tissue damage/death
-Promotes recuperation and healing
-Basically an alarm system to say something is wrong and to fix it
What is the social pain hypothesis?
What is the neuroimaging evidence that supports this hypothesis?
What is the evidence of shared sensitivity to physical and social pain?
What is the evidence that factors that increase/decrease one type of pain have the parallel effect on the other type of pain
Social pain (e.g., responses to rejection or exclusion) may have evolved from physical pain to promote group cohesion and to motivate reconciliation –> critical for survival
Neuroimaging Evidence: Cyberball exclusion related to increased activation in dACC and AI (brain areas related to the affective component of pain)
Greater baseline sensitivity to physical pain predicts greater sensitivity to social exclusion
- Those with the genetic variant related to greater physical pain also have greater rejection sensitivity and more sensitive to social pain in general.
Factors that decrease social pain have
parallel effects on physical pain
- Social support decreases physical pain
Factors that increase social pain have parallel effects on physical pain
-Intentional acts hurt more than unintentional acts
- Cyberball exclusion leads to pain hypersensitivity
- If someone is emotionally numb, they also exhibit hypoalgesia
Factors that increase physical pain have
parallel effects on social pain
- People on Tylenol report lower levels of hurt feelings
- Inflammation increases interpersonal sensitivity
What are the behavioural consequences of social pain?
Social pain drives affiliative behaviours
- Increased desire to work with others
-More likely to sign up for friend matchmaking services
-Pay more attention to social information
-Lesions to dACC and AI lead to less separation distress and higher social inhibition
BUT want to connect only to the extent that we think its possible
-Being highly fearful of negative social evaluations less likely to affiliate
- Won’t try to affiliate with those who rejected you.
Social pain may also lead to aggressive behaviours when we feel like we cant escape the situation
What is the distinction between wanting and liking? How can we measure wanting and liking?
Anticipating and actively seeking something good (wanting) is different from actually
receiving and enjoying something good (liking)
Wanting = something we will work to achieve, the sense of anticipation, measured by the amount of effort we exert to obtain the reward
Like = something that gives us pleasure, measured by analyzing spontaneous facial expressions
What role does dopamine play in processing reward?
Plays a role in motivation or wanting NOT liking
What are the components of the dopamine-based reward circuit?
- Begins in the ventral tegmental area (VTA), where
dopamine is synthesized
-Released into the nucleus accumbens (NA): brain’s
“pleasure center”
-Circuit extends to the prefrontal cortex (PFC), which is
involved in decision-making & self-regulation. Where we process the subjective experience of pleasure - Also extends to orbitofrontal cortex (OFC), key for
evaluating reward value of stimuli
When is dopamine release strongest?
-Highest when the the reward is unexpected or underpredicted –> when the prediction error is positive (what we got is larger than what we expected)
-Higher during the anticipation of a reward NOT the receipt of the reward –> about learning and motivating goal-directed behavior
What role do endogenous opioids play in reward processing?
Play a role in liking/pleasure –> for the hedonic experience
What are opioid receptor antagonists and how do they help us study the role of endogenous opioids?
Substances that block endogenous opioid signals –> can be used to see how endogenous opioids affect us by removing their effect
Describe the motivation-decision model of pain. In what circumstances is the brain likely to reduce pain signals? What biological mechanisms play a role in this type of analgesia?
Subjective interpretation of a sensory event
can be understood as manifestation of
unconscious decision process in which decisions are based on what is most crucial for survival in the moment –> influenced by our internal state, sensory input, and the presence of threats/rewards
i.e. if we are starving, we will endure pain if that secures us food
If something more important than pain is
happening, the brain can reduce pain signals
to allows us to focus on that bigger priority
i.e. Injured mouse will have an analgesic response when being predated by a cat.
This analgesic effect is caused by the production of endogenous opioids during stress and pleasure induced situations
i.e. rewarding stimuli like sweet foods, pleasant music, sex, can reduce pain
What is placebo analgesia?
Reduction in pain that occurs after a person is given a placebo –> thinking something will reduce pain will cause the release of endogenous opioids
-Placebo effect is removed if given an opioid receptor antagonists
-Placebo analgesia is also created by the release in dopamine in situations where reward is expected –> strong reward expectation leads to stronger analgesic response to placebo
What is anhedonia?
Inability or decrease in enjoyment of rewarding activities –> often caused by chronic pain
At the neuroanatomical level, what are the points of overlap between pain and pleasure processing discussed in class?
Anterior cingulate cortex: associated with the motivational-effective component of pain AND represents the the size and probability of rewards and the effort we put into obtaining them
The insula: Related to A-M component of pain AND is involved in encoding interoceptive signals such as taste
Amygdala is involved in both pain and threat processing and reward
Why do we sometimes seek out painful experiences?
-Because the relief of pain is a pleasurable experience.
-Pain provides a contrast to pleasure or to even worse pain
Describe the research evidence showing that relief from pain is a positive hedonic experience?
Ps subjected to painful tasks (application of heat, skin
irritant capsaicin)
When painful sensation is suddenly terminated, a
sense of relief and positive affect results –> leads to pleasure
The more intense the pain, the more intense the relief
Describe the opponent-process model. What are the differences between State A and State B? .What happens with repeated administration of the stimulus?
-Emotional reactions are regulated by the brain
to maintain hedonic balance
-Strong emotional reactions (both pleasure and
pain) are countered by an opposite reaction
State A: initial reaction to emotionally powerful stimuli
-Develops quickly
- associated with intensity of stimulus
-Ceases when stimulus is removed
State B: Counterreaction to maintain homeostasis
- slower onset and slower offset
- continues even after A
State B becomes more intense with repeated administration of the stimulus and thus State A will lose its effect over time
What is the peak-end rule?
The most intense positive or
negative moments (the “peaks”) and the final
moments (the “end”) of the experience are most
heavily weighted in our recollections of the
experience
