simple decisions, thoughts and metacognition Flashcards
Reaction time in MDD
Patients with major depressive disorder tend to have a slower reaction time
Slower RT - Biological perspective
Cascade of processes each time we process something
Lots of parallel elements in brain happening
Slower RT - Metacognitive perspective
There can be many things going on i someone’s mind when they try to approach a task, leading to slower reaction times
Why does RT increase with MDD
Can be caused by distraction from intrusive task-unrelated thoughts
Hard to truly measure what’s on an individual’s mind
How to measure whats on patient with MDD mind
Thought probes in boring study designed to measure objective performance
Mood induction doesn’t have an effect on individuals with non depressive tendencies
Brain dynamics
Different brain networks are active at different times
We can measure these states with MRI
Central executive network
Active when doing calculations
Active when doing rational choices
Default mode network
Active when resting
Role is to think about internally driven thoughts
Salient network
Activates like a switch
Activates to salient stimuli (like people)
Depression and brain dynamics
In depression, brain reacts less to salient stimuli and will default more to default mode network
Brain will deplete resources that central executive network will need to function and do essential tasks, reducing performance
Meta awareness task (mindfulness)
Depressed people made more mistakes
Higher mindfulness associated with lower tendencies of depression
Doesn’t mean mindful people are less depressed, may be that depressed people struggle to be mindful
Two types of mind wandering
Spontaneous
Deliberate
ADHD and mind wandering
Students diagnosed with ADHD engage in spontaneous mind wandering
ADHD and metacognitiion
People with ADHD are slower and more variable over time
People with ADHD tendencies (not diagnosed) have similar pattern just less pronounced
Thoughts and test performance
People relate not being on task to thinking of different things
Performance is poor on tasks when individuals are tuned out
ADHD and performance variability
Three stages, detection, decision and execution
Differences between patients and control in reaction time can differ in any of the stages or a combination of them
Drift diffusion model of performance variability
Accumulate evidence for a decision over time
Collect evidence until decision is reached
Determines the choice and its reaction time on each trial
Boundary separation model of performance variability
If difference between boundaries is large it will take longer to commit to a decision
If difference between boundaries is small it will take shorter to commit to a decision
Can be a trade off between accuracy and speed
Drift rate model of performance variability
How quickly the evidence accumulates
If the evidence is of good quality then it will take less time to reach the boundary
If the brain is not as fast at accumulating the information then it will take longer to reach the boundary
Decision modelling and ADHD
Reduced processing efficiency
Less cautious boundary separation
Faster sensory and motor processes
How do parameters differ in ADHD individuals and non ADHD individuals (Karalunas)
Slower drift rate in ADHD (Reduced efficiency)
Narrower boundary separation in ADHD (Impulsivity)
Faster non decision time in ADHD
Affect of alcohol on decision making
Decreases drift rate
Alcohol decreases processing efficiency
