Cognitive Control Flashcards
• Cognitive Control & Frontal Lobe Areas • Working Memory • Goal-Oriented Behavior • Performance/conflict Monitoring • Frontal Lesions
When do we need cognitive control?
• Tasks that involve planning or decision making
• Tasks that involve error correction or troubleshooting
• Learning, using, remembering, or switching between rules
• Novel, dangerous, or technically difficult situations
• Situations which require the overcoming
of a strong habitual response, resisting temptation, or ignoring irrelevant information
Working
Memory
• Working memory = “blackboard of the mind” • Integrating current perceptual information with stored knowledge • Manipulation of information in memory • Lateral prefrontal cortex
Working Memory
&
PFC
Delayed Response Task
- ‐ Continue to represent location of unseen food during delay
- ‐ No explicit cue during delay
- ‐ Prefrontal lesions disrupt performance
Object permanence tasks in babies:
“Out of sight, out of mind.”
Associative Task
- ‐ Food reward always associated with particular visual cue
- ‐ Cues always visible
- ‐ Requires long-term memory
- ‐ Prefrontal lesions do NOT disrupt performance
Working Memory & PFC:
Neurophysiology Example
– Delayed response task
– Prefrontal neurons:
sustained activity during delay period
Working Memory & PFC:
fMRI Examples
– WM task: was test face part of studied set? – FFA: activity only when faces being presented – PFC: sustained activity during delay period
– ”N-back task”
. Activation in lateral PFC increases with load
Hierarchical Organization of the PFC
The more complex/abstract the task, the more anterior regions get involved
– Evolutionary?
Goal-Oriented Behavior
• Planning & selecting an action
• Identify goal
– Planning ahead
– Using past experiences
• Anticipate consequences
– Flexible and adaptive
• Self monitor
Frontal lobe patients are impaired at all steps
Decision-making & Reward
• Decision:
selection of 1 option among others based on
anticipated consequences
• Reward:
value of consequences
– Value judgments/comparisons in orbitofrontal cortex
• Prediction error:
difference between expected & actual reward
– Dopamine neurons fire accordingly
Tests of Cognitive Control:
Wisconsin Card Sorting Task
Wisconsin Card Sorting Task
– Cards contain objects varying along 3 dimensions (shape, color, number)
– Cards presented 1 at a time, subject must decide how to sort
– Experimenter sets rule
• Subject must discover through trial & error
• Experimenter can change rule; subject must adapt
Frontal patients perseverate
(do not adapt, continue to apply initial rule)
• *Psychology Experiment Builder Library
– Free platform to run common behavioral experiments yourself
– hjp://pebl.sourceforge.net/bajery.html
– {Applications/PEBL»_space;> BCST}
Task
Switching
Often multiple different tasks simultaneously available to perform
• How do we choose relevant task?
• How do we switch between tasks?
• There a cost to multitasking. Switching between tasks is less efficient than repeating them.
. Assembly line production
. Checking email in class
• Even with preparation time, still see “switch cost”
– Frontal patients really bad at task switching
Goal-Oriented
Behavior
Dynamic Filtering Hypothesis:
. Prefrontal cortex selects information that is most relevant for your current task demands
. Does this account for frontal patients’ difficulty with Task-switching / Wisconsin Card Sort task?
. Does this account for Stroop interference?
Filtering & PFC
ERP Example
– ERP Responses to auditory clicks (unattended)
– Patients with damage to auditory cortex
»> reduced response
– Patients with damage to frontal cortex»_space;> amplified response (can’t inhibit)
Filtering & Cognitive Control
Dynamic filtering requires top-down control
. Select task–]relevant information (facilitation/enhancement)
. Suppress task-irrelevant information (inhibition)
Filtering & Cognitive Control
fMRI example
– Remember scenes»_space;> enhancement of scene processing compared to passive
– Ignore scenes»_space;> suppression of scene processing compared to passive
– Older adults don’t show suppression (PFC affected with aging»_space;> less inhibition)
Inhibition of Action Plans
– Sometimes need to cancel action plan
. Baseball example
– In the lab: Stop-Signal (or Go-No-Go) Task
. Respond as quickly as possible on ”go” trials
. Suppress response on ”stop” (no-go) trials
. Sometimes fail to stop
. {PEBL Demo}
. fMRI: Frontal cortex important for inhibitory ”stop” signal
. Chronic cocaine users perform worse on task and have lower activation in frontal cortex
