Lecture 10- Cognitive Control 1

Question 1

What is cognitive control?

Answer 1

The set of psychological processes that contribute to planning, controlling and regulating the flow of information processing

These processes bias the selection of action and thoughts
to enable goal-directed behaviour

Question 2

Who is Phineas Gage?

Answer 2

• 25 year old, male
• Railroad foreman
• Worksite injury, solid recovery
• “ the lesion the ventromedial region of both frontal lobes while sparing the dorsolateral.”
• Before: “efficient, well-balanced, shrewd, and energetic”
• After: When he returned to work, others noticed significant behavioural changes - “no longer Gage”
• Shows that the frontal lobe is invovled in personality

Question 3

What other case study (aside from Phineas Cage) shows how damage to the frontal lobe results in defecits?

Answer 3

• 50 year old, male, married
• Attorney for successful Fortune 500 company
• Left frontal glioma discovered and removed - solid recovery

-When returning to work, recalled professional obligations but lacked
concentration and eye for detail, illogical outputs
-Made careless errors, increasingly erratic performance
-Apathetic to professional and personal losses although aware of shortcomings
-Lack of emotional response: no embarrassment or shame

Question 4

What areas are there in the frontal cortex?

Answer 4

• Primary motor cortex
• Frontal cortex including the premotor cortex
• Prefrontal cortex (the dorsolateral prefrontal is behind and the ventrolateral prefrontal across ish)
• Orbitofrontal cortex is the part behind the eyes

Question 5

In a medial view of the brain what areas can be seen in the frontal cortex?

Answer 5

• Medial prefrontal cortex
• Anterior Cingulate gyrus (above the corpus callosum)
• Supplementary motor area (in front of the motor cortex/ precentral gyrus)

Question 6

What is the spectrum that exists in relation to cognitive control?

Answer 6

Continuum exists from habits to goal-directed

Habits= automatic responses to stimuli in the environment. They have a low level of conscious control.

Goal-directed= high level of conscious control, planned

Question 7

What are the four key components of cognitive control?

Answer 7

• Working memory
• Inhibitory control
• Set-shifting
• Abstract thought

Question 8

What is the difference between a working memory task and an associative memory task? Which is the prefrontal cortex essential for?

Answer 8

• Working memory task: delay match to sampling. Animal presented with cue (food under one card, no food under other). Task is to remember where the food was after a delay. Working memory is required for this tasks because at response, no external cues indicate location of food.
• Associative memory task: The animal learns to associate a certain symbol/ external cue with where the food is and so will select the card with the symbol no matter what side it is on in order to receive the reward (food).
• These tasks can be used to show that prefrontal cortex is essential for working memory but not for associative memory as animals with prefrontal lesions were impaired in the first task but not the second.

Question 9

What is a non-match to sampling task? What can they show?

Answer 9

• Like match to sampling task where presented with a cue and then given delay and have to make a decision. But this time the animal has to choose what they haven’t seen before (doesn’t match the cue).
• Again these tasks require working memory and therefore prefrontal lesions will impair performance.

Question 10

Explain the idea of ‘delay cells’ in the prefrontal cortex…

Answer 10

-In a delayed response task, some PFC cells respond during the cue
period, others during the delay period this leads to the term ‘Delay cells’
-This links to Hebb as firing continues in order to keep representation of memory alive

Question 11

What is the n-back task?

Answer 11

• Indicate when the current stimulus matches the one from n steps earlier in the sequence (ignoring letter case).
• Is a test for working memory

Question 12

In the n-back task what is a lure?

Answer 12

Lure is something that nearly qualifies as a target but isn’t. For example, in a 3 back task if the current stimulus matched the one from 2 steps earlier.

Question 13

What is increased Prefrontal activity during lures associated with in the n-back task?

Answer 13

• Greater working memory span
• It potentially indicates better ability to suppress non-relevant information (response to lures)
• Activity in the brain shows you are aware that the stimulus is very similar to the target but you stop yourself from responding

Question 14

What is a famous test of working memory and by extension prefrontal cortex function?

Answer 14

The Tower of London test: have to move coloured balls on sticks from an initial configuration to a target configuration within a specified number of moves. One ball at a time, max 2 on middle post, max 1 on left post. Complexity increases.

Question 15

What were the results of a meta-analysis of activation during the Tower of London task?

Answer 15

Showed that Brodmann Area 46 in the dorsal lateral prefrontal cortex is activated during working memory tasks

Question 16

What does prefrontal cortex allow for in relation to the temporal cortex?

Answer 16

Manipulation of representations

Question 17

What is utilization behaviour?

Answer 17

• Patients behavior driven by cues in environment
• Sees glasses and uses them as intended (put them on) despite not being socially appropriate to do so (they were the experimenters, already had multiple pairs of glasses on etc.)
• Damage to prefrontal cortex results in the above behaviour due to lack of inhibitory control

Question 18

How does the 55 year old, widowed female case study show how damage to the prefrontal cortex can result in a lack of inhibitory control?

Answer 18

-Administrative assistant in professional office
-Olfactory meningioma discovered and removed, solid recovery
-When returning to work, no evidence of cognitive impairment in
professional obligations
-Began to repeatedly approach complete strangers for sex
-Recognized her impulsivity and that she “lacked brakes” – but continued despite negative consequences

Question 19

How does Phineas Cage illustrate a lack of cognitive control?

Answer 19

“impatient of restraint or advice when it conflicts with
his desires, obstinate, devising many plans of operation which
are no sooner arranged than they abandoned in turn for others appearing more feasible”

Question 20

How is the Wisconsin card sorting task a test of frontal lobe function?

Answer 20

• Cards differ in colour, number of symbols, shape of symbols
• Could therefore sort multiple ways: not told which way is correct
• Might have a couple of incorrect responses and then would learn what ‘rule’ the experimenter was following
• After the 10th response the rules suddenly change and the patient starts sorting wrong again
• Healthy controls will adapt to the new rule while those with prefrontal damage will continue sorting via the category that was initially correct. They are described as cognitively fixed and most of the time are aware that they have become so but cannot stop.

Question 21

What area of the brain lights up during the WCST task?

Answer 21

• Dorsolateral Prefrontal cortex
• And the degree of activation increases as the test becomes more complex i.e. least activation when the sorting information is provided to participants, next least when it is provided at each new stage and the most during the standard test when participants have to work out the rules themselves and adapt to changes.

Question 22

What is self control?

Answer 22

• Where previously reinforced, highly reinforcing, or well learned (habitual) responses have to be suppressed (think Mischel’s Marshmallow Test)
• In most cases the reasons for suppression is a social context

Question 23

What does self control allow for and what are it’s benefits?

Answer 23

-Self-control encompasses behaviours that enable us to forgo immediate temptations in favour of more beneficial delayed rewards. –Self-control has been associated with superior academic, professional, and personal outcomes.

Question 24

What has self control tested at age 3-11 being correlated with?

Answer 24

• Criminal convictions as adult (age 32), various wealth/ financial outcomes.
• In other words, low self control early on predicted unfavorable outcomes

Question 25

What developmental changes occur in prefrontal cortex? What might any immaturities explain?

Answer 25

• In scans blue indicates mature areas where there are not any further changes to synaptic connectivity. This technique reveals that the dorsoprefrontal cortex remains relatively immature (green in scan) even at age 20
• This is also revealed by analyzing dendritic spines as in puberty there is still relatively high numbers in the dorsoprefrontal cortex. High numbers of dendritic spines indicates immaturity as synaptic pruning has not yet occurred to refine connections (conserves energy).
• This may explain why teenagers are more impulsive

Question 26

What does Behavioural performance in an emotional go/no-go task indicate about the brains of teenagers?

Answer 26

• Calm faces are target (go) stimuli, happy faces are non-target (no-go) stimuli
• Teenagers found it hard to withhold pressing button for happy faces indicating a lack of inhibitory control and an underdeveloped dorsolateral prefrontal cortex.

Question 27

What part of cognitive control does the trail making task relate to?

Answer 27

Set shifting: in task first just have to follow a route via numbers, then the task gets more complex as you have to swap between numbers and letters to find the way
-Increased dorsal prefrontal thickness associated with higher TMT-B scores indicating that the dorsal prefrontal cortex is needed for set shifting

Question 28

To summarize what does damage to the dorsolateral prefrontal cortex cause?

Answer 28

-Damage to the region is associated with utilization behaviour,
perseveration, environmental dependency

-Many of these behaviours result from a reduction in self-control and
behavioural flexibility.

-Working memory underlies many aspects of behavioural flexibility