Chapter 15

Question 1

Executive functions

Answer 1

• Needed to optimize performance in situations that require coordination between a number of cognitive processes.
• Supervisory, controlling or meta-cognitive, rather than specific to one domain (memory, perception, language).
• Linked to distinction between automatic and controlled behavior (latter requires executive functions, cfr. SAS model).
• Linked to prefrontal cortex (PFC).

Question 2

Executive functions in (clinical) practice - working memory

Answer 2

• VLPFC: Maintaining & retrieving information.
• DLPFC: Manipulation of information.

Question 3

Executive functions in (clinical) practice - task-setting (open-ended) and problem solving

Answer 3

• Related to (lay) notions of (fluid) intelligence.
• Tower of London task: DLPFC activated in functional imaging during task (healthy participants), and damage to left PFC results in poor performance.
• Cognitive Estimates (Shallice & Evans, 1978) e.g. “How many camels are in Belgium?”
• Cognitive fluency (FAS test): generate as many words beginning with “F” (or “A” or “S”) in one minute.

Question 4

Executive functions in (clinical) practice - overcoming prepotent or habitual responses

Answer 4

• Stroop Test: functional imaging and lesion studies suggest involvement of anterior cingulate cortex.
• Go/No go Test.
• Related to concept of inhibition.
• Anterior cingulate & pre-SMA.

Question 5

Executive functions in (clinical) practice - task switching

Answer 5

• Wisconsin Card Sorting Test.
• WCST requires rule inference, and unpredictable switches.
• More simple studies developed that isolate different aspects of a switch (and used more in healthy participants rather than patients).
• Does switch cost reflect setting up the new task or inhibiting the old task?
• Greater switch cost when switching from hard to easy.
  * from second language to a first.
  * from colour naming to word naming in the Stroop.
• fMRI: several regions, incl. pre-SMA.

Question 6

Executive functions in (clinical) practice

Answer 6

(1) Working memory, (2) task-setting (open-ended) and problem solving, (3) overcoming prepotent or habitual responses, (4) task switching, (5) multi-tasking: six element test, (6) planning of (unstructured) activities in daily life.

Question 7

The organization of executive functions

Answer 7

(1) Emotional versus cognitive control, (2) multiple-demand network, (3) posterior versus anterior lateral PFC, (4) left versus right lateral PFC, (5) anterior cingulate versus lateral PFC

Question 8

The organization of executive functions - emotional versus cognitive control

Answer 8

• Orbitofrontal and ventromedial PFC: control of affective or reward-related stimuli
  
  • acquired sociopathy
    (Anti-social personality disorder)
• Lateral prefrontal cortex: control of purely cognitive stimuli
  
  • dysexecutive syndrome

Question 9

The organization of executive functions - multiple demand network

Answer 9

• Tests of executive function and fluid intelligence (e.g. Ravens matrices) use the same brain regions (so called ‘multiple demand network’)
  Includes lateral PFC, IPS, and anterior cingulate.
• Damaging PFC impairs performance on both measures but NOT on crystallized intelligence (e.g. WAIS)

Question 10

The organization of executive functions - posterior versus anterior lateral PFC

Answer 10

• Anterior lateral PFC: involved when multiple tasks need to be coordinated.
• Posterior lateral PFC: involved in tasks with a single goal.

Question 11

The organization of executive functions - left versus right lateral PFC

Answer 11

• Left lateral PFC: involved in task setting
  * E.g. Tower of London, open-ended (standard) version of WCST
  * Task switching – much slower to switch
• Right lateral PFC: involved in task monitoring and sustained attention
  * E.g., Predictable version of WCST impaired
  * Task switching – more likely to revert to previous rule

Question 12

The organization of executive functions - anterior cingulate versus lateral PFC

Answer 12

Monkeys with lesions here don’t trouble shoot after making an error (error+1 trial worse than correct+1)
- Might be source of error potential:
error-related negativity
- fMRI shows activity greatest on error trial, but lateral PFC greatest on error+1 trial
- Suggests anterior cingulate detects but doesn’t correct errors

Question 13

Executive functions

Answer 13

Control processes that enable an individual to optimize performance in situations requiring the operation and coördination of several more basic cognitive processes.

Question 14

Self-ordered pointing task

Answer 14

A task in which participants must point to a new object on each trial and thus maintain a working memory for previously selected items.

Question 15

FAS test

Answer 15

A test of verbal fluency in which participants must generate words beginning with a letter in a limited amount of time.

Question 16

Stroop test

Answer 16

Response interference from naming the ink color of a written color name.

Question 17

GO/No GO test

Answer 17

A test of response inhibition in which participants must respond to a frequent stimulus but withhold a response to another stimulus.

Question 18

Impulsivity

Answer 18

A behavioral tendency to make immediate responses or seek immediate rewards.

Question 19

Wisconsin Card Sorting Test

Answer 19

A test of executive functions involving rule induction and rule use.

Question 20

Perseveration

Answer 20

Failure to shift away from a previous response.

Question 21

Task-switching

Answer 21

Discarding a previous schema and establishing a new one.

Question 22

Switch cost

Answer 22

A slowing of response time due to discarding a previous schema and setting up a new one.

Question 23

Multi-tasking

Answer 23

Carrying out several tasks in succession; requires both task-switching and maintaining future goals while current goals are being dealt with.

Question 24

Multiple-demand network

Answer 24

A set of brain regions in the lateral prefrontal and parietal lobes activated by a lage range of tasks relative to baseline.

Question 25

Fluid intelligence

Answer 25

Flexible thinking an problem solving in novel situations, independent of acquired knowledge.

Question 26

Crystalized intelligence

Answer 26

The ability to use prior expertise and knowledge.

Question 27

Monitoring

Answer 27

The process of relating information currently held in mind back to the task requirements.

Question 28

Sustained attention

Answer 28

Maintaining focus on the task requirements over a period of time.