Decision Neuroscience Flashcards
What are primary and secondary reinforcers? What are the factors that contribute to value?
Primary reinforcer: direct benefit for survival, e.g. food, water
Secondary reinforcer: rewards that hold no intrinsic value, but become rewarding due to their associations with other things e.g. money, status
Factors:
Payoff: How large is the reward?
Probability: how likely are you to gain the reward?
Effort or cost: How long are you willing to wait for the reward?
Context: external things e.g. time of day,
Preference: may like one more than other
What is the difference between reasoning and decision making?
Reasoning: All information is available.. if A then B
Decision Making: Not all information is available, weigh possible choices using risks/rewards
What is the utility theory?
Each decision has costs and ebenfits based on personal goals
Costs: move us away from our goals
Benefits: move us towards our goals
Decide by choosing actions with more favourable benefits
We estimate a subjective utility for each item
In case of uncertainty or risks, we estimate the expected utility
What are the predictions of the utility theory?
People seek ways to maximise utility in their choices
People seek options with the greatest expected utility
What are the issues with the utility theory?
People have unlimited knowledge
People have unlimited time
People have unlimited processing power
What are neuroeconomics? How did this branch develop?
Economic models need Psychology to make better predictions
Psychology needs economic models to take advantage of normative frameworks e.g. models/formulas, testable paradigm
Psychology and Neuroscience need biological insight into the distinct processes involved in decision making
What is homo economicus?
People attempt to maximise utility as a consumer and economic profit as a producer
However, humans aren’t rational entities so maximising utility and therefore economic models need to consider more than utility
What is metacognition in decision making?
A decision can be binary (yes or no) or discrete
Underlying model is likely a probability distribution, this is how the brain encodes uncertainty or confidence
What brain areas are important for decision making and for confidence in decisions?
Prefrontal cortex is important to make a binary decision and reflect on decision making processes
Right inferior prefrontal gyrus associated with confidence in a decision, not always associated with accuracy
Frontoparietal lobes
More active the harder the decision is
What was the procedure for the Iowa gambling task?
A and B are bad decks
C and D are good decks
Ps select from a deck of cards, ps don’t know if the deck is good or bad
Some deck’s are bad or good according to the researcher
In bad decks, you lose money and in good decks, you gain money
In bad decks, you gain money then lose more money the more cards they use
In the good decks, they gain more money the more cards they used
Every 20 cards, ps asked about their knowledge of the situation and their feelings about it
Also skin conductance responses (SCR).
What were the results to the Iowa gambling task?
After experiencing losses, people still aren’t aware what;s going on
SCR: Their body is aware that picking cards is risky but they’re not explicity aware
After 50 cards, people start to think that the bad decks are risky, even though they originally thought the bad decks were good at first
They know excplicity know the decks are bad
After 80 cards, they can tell the researcher that decks A and B shouldn’t be chosen from
What is the somatic marker hypothesis?
We have emotional systems that guide our decisions even before we have awareness of a situation
What happens to lesion patients in the Iowa gambling task?
Lesion patients
Those with amygdala or VM lesions (ventral medial prefrontal cortex) performed worse than control group
Patients with lesions failed to learn or adapt their responses to the blocks of cards
Control ps over time knew that the bad decks A and B weren’t the decks to choose from
Whereas lesion patients weren’t learning this
What is the role of the amygdala in the somatic marker hypothesis?
Encodes the emotional reaction to bad stimuli (losses)
What is the role of the VM in the somatic marker hypothesis?
Receives information from amygdala which recalls the emotional reaction and uses it to guide behaviour
What other processes are important for decision making that aren’t neurological?
Process other than rational thinking to contribute towards decision making
Emotional and automatic processes
Conscious gut feelings
Unconscious processes
What is time discounting?
Requires self control
Time discounting: a reward loses value if it is delivered later in time e.g. marshmallow test, where children are offered a marshmallow but if they can wait a few minutes they can receive 2 marshmallows
What brain areas are used in time discounting?
Ventral medial prefrontal cortex and striatum respond to immediate rewards
Dorsolateral prefrontal cortex responds to all the options, and is not related to the immediacy of the rewards (related to high cognitive function)
What did Hare et al 2009 find on food preferences in the dorsolateral prefrontal cortex?
People chose whether nor not to get a food item based on its tastiness and on its healthiness
Those who onsidered both tastiness and healthiness classified as a greater self controller, exhibiting higher activation of the dorsolateral prefrontal cortex
What was the study with monkeys on fairness?
2 monkeys
Give cucumber to both monkeys if they complete task
Another variation: One monkey gets grapes and the other gets grapes for the task
When the monkey sees the other one gets grapes, the monkey throws away the cucumber and gets agitated
What is game theory?
Players: people, genes, groups, firms
Actions/Strategies: approach or avoid, amount to bid, settle or sue, attack or retreat
Outcomes: points, victories, selling rights, food, sexual opportunity, political power, social justice
Equilibrium: solution in which each plater chooses a strategy that is the best, given all the possible conditions and has no interest in changing it
What is the ultimatum game?
Prediction: people will always accept 1>0
Reality: responders tend to reject unfair offers so proposers making fair offers
What are the social motivations for decision making?
Strongly linked to emotions, positive and negative
People receive utility from giving rewards
Irrationality derives from involvement of anger, guilt, shame, reward from revenge
What brain areas are used in cooperation? How does this relate to reward processing?
People want to cooperate
Activation of striatum and orbitofrontal cortex (reward areas) for mutual cooperation
Strength of striatum activation predicts future cooperative choices
When is altruism rewarding?
Across a number of games e.g. ultimatum, areas associated with reward are activated during altruistic decisions
Especially striatum
Mentalizing networks: self other boundaries, reputation, consider emotions and thoughts of others
Emotion/salience networks: interoceptive info, attention to emotional stimuli (especially negative)
What brain areas are associated with unfairness being frustrating? What brain areas find unfairness to not be frustrating?
SCR is higher for rejected ultimatum game offers
People are angry when rejected
Anterior insula activation is higher for rejected ultimatum game offers
Anterior insula is associated with negative interpretation of emotion/bodily reaction to emotive stimuli
Unfairness is associated with negative feelings in oneself or directed towards empathetic processing of others
No differences in the dlPFC activtion for rejections and acceptance
dlPFC is known for self control. Accepting fair offers equires lots of self control
What brain areas are associated with punishment as a reward?
Striatum (reward area) has higher activation when people are given the opportunity to spend money in order to punish those who have betrayed them in a prisoner’s dilemma
People who are rewarded by punishment more than money
What is the prisoner dilemma?
Prediction: People will defect
Reality: People cooperate (stay quiet/stay quiet)
Cooperation until someone defects (informs)
