L10: Decisions, metacognitions and modelling

What are the two perspectives for why some mental processes are slower and more variable in some people than in others?

1. Biological perspective

   • Neuroscience

2. Metacognitive perspective

   • The process of thinking about one’s own thinking

     • Attention

     • Motivation

     • Confidence (monitoring)

Why does mean RT increase with depression: What is the impact of negative and positive mood induction on depressed and non-depressed people?

Negative mood induction is effective on depressed people

Brain dynamics: Which brain areas are involved with rumination

• Central Executive Network

  • Focus on completing task

• Default Mode Network

  • Self-centered

  • Involved in daydreaming and rumination

• Salience Network

  • Switches between the CEN and DMN

  • Dynamic switching

What brain network becomes more prominent with Depressed people

Default Mode Network

• Idea that Salient network very receptive to negative triggers, so dynamic becomes shifted towards DMN over CEN

Sustained Attention to Response Task (SART)

Boring task to measure attention i.e. Go/No-Go Task

If someone is ‘Tuned out’ what does this mean?

Mind-wandering with meta-awareness (i.e. person is mind wandering but aware they were mind wandering)

If someone is ‘Zoned out’ what does this mean?

Mind wandering without meta-awareness

What is one theory for why people with Depression have some slower mental processed

They find it difficult to focus on a repetitive task over time, may be due to rumination

What are the two types of mind wandering: ADHD

1. Spontaneous

   • I find my thoughts wandering spontaneously

2. Deliberate

   • I allow my thoughts to wander on purpose

What results did Seli et al. (2015) find on types of mind wandering and ADHD

Those with ADHD engaged with more spontaneous MW than control students (lapse in attention)

ADHD and performance variability

People with ADHD showed slower overall RT, BUT also showed mych high variability than controls (fast sometimes slow others)

• May be due to lack of focus

Experiment looking at how whats on our mind relates to task performance

Metronome task

• Someone press button same time as hearing a tone (very boring)

Results

• Robust but weak relationships between performance and subjective report of “on-taskness”

What does ‘off-task’ states relate to

Poorer performance, slower RT, higher variability

The drift-diffusion model (Ratcliff et al., 1978)

• Individuals accumulate evidence favouring one or another possible response

• When enough evidence accumulates to reach a criterion (threshold), a decision is made

• Evidence is made up of information and noise (random processes occurring unrelated to the decision being made)

What are the parameters that impact decision making in the drift-diffusion model

1. Boundary separation

   • How big is the gap between the criterion for the two potential responses (i.e. Yes or No)

     • Is the threshold 0.1? 0.001?

   • The amount of evidence needed to commit to a decision

   • Speed-accuracy trade-off

     • More evidence = less likely to make error and visa versa

2. Drift rate

   • The average speed of evidence accumulation

   • The quality of evidence (signal strength)

   • Efficiency of someone performing the task (how easy the task is for you)

3. Non-decision time

   • Everything that is not taking place during the Decision process (Detection, Decision, Execution —> Donner’s processes model)

   • RT = Decision time + Non-decision time

What do the parameters in decision modelling capture

• Process efficiency (drift rate)

• Caution/ impulsivity (boundary separation)

  • Sensory and motor process speed (Non-decision time

How do parameters differ between people with ADHD and controls?: Metanalysis by Karalunas (Boundary Separation, Drift-rate, Non-decision time)

1. No evidence of difference in boundary separation

   • Narrower boundary separation would have indicated more impulsivity

   • May have less cautious boundaries but weak evidence

2. Slower drift rate in ADHD

   • Reduced decision efficiency

3. Some studies suggest faster non-decision time in ADHD

   • Not consistent across the board

   • Suggests faster visual and motor processes in ADHD

     • Counteracted by lack of efficiency