Lecture 19 Flashcards
(20 cards)
What three factors influence the dynamics of decision-making?
1) Evidence strength (accumulation rate), 2) Threshold level, 3) Response bias (starting point).
Which brain regions support perceptual evidence accumulation in monkeys?
MT signals momentary evidence; LIP accumulates evidence toward threshold.
What does LIP activity indicate about decision thresholds?
LIP activity peaks at the same level just before action, consistent with a decision threshold.
How does stimulating MT influence decision-making?
It alters the motion evidence that LIP accumulates, changing perceptual decisions.
Which areas track perceptual evidence in humans?
FFA and PPA for face/scene evidence; LPFC for cumulative evidence.
How is value-based decision-making structured in the brain?
Different regions signal momentary value (e.g., amygdala, vStr); vmPFC accumulates and integrates.
What does vmPFC activity reflect during value-based choices?
The difference in value between chosen and unchosen options.
What regions may specialize in different value types?
vmPFC may encode stimulus value; ACC may encode action value.
How does attention influence decisions?
Focusing on an option increases its impact on the decision (attention-weighted accumulation).
What does vmPFC track during attentional shifts?
The value difference between attended and unattended options.
What are the competing systems in action selection?
Habit, Pavlovian, and deliberative systems (involving striatum and PFC).
How does behavior shift from goal-directed to habitual?
Control shifts from medial to lateral dorsal striatum; DMS lesions increase habits.
How can Pavlovian responses interfere with goal-directed actions?
Cues can trigger responses that conflict with current goals, via amygdala and vStr.
What biases influence deliberation?
Status quo, defaults, heuristics, anchors, and biased starting points.
What brain regions help override these biases?
ACC and LPFC, similar to cognitive control tasks like Stroop.
What is confidence monitoring in decisions?
Tracking how sure we are, influencing real-time adjustments and future learning.
Which brain region monitors confidence and conflict?
Anterior cingulate cortex (ACC).
How can we exert control over decision processes?
By shifting attention, adjusting thresholds, or modifying how values are compared.
What is choice deferral and when is it likely?
Postponing decisions, often when options are similar or both unappealing.
How might deferral relate to procrastination?
Ongoing avoidance of choice, especially under conflict or low motivation, may result in procrastination.
