Cognitive Control Flashcards
input
External input might include things like visual or auditory information (e.g., a traffic light changing from green to red).
Internal input could include thoughts, memories, or emotions (e.g., remembering a deadline or feeling anxious about an upcoming task).
often very complex, loads of stimuli processing
output
External output might include physical actions, such as pressing a button, speaking, or moving your hand to write something.
Internal output could involve changes in mental processes, such as adjusting focus or rethinking a decision.
habits
Action is automatically triggered by a stimulus or context
* Not under voluntary control of a desired outcome/goal/reward
goal-directed action
Action to achieve a desired outcome/goal/reward
* Requires knowledge of a relationship between action and outcome
* Cognitive control is needed for goals to influence behaviour
two prefrontal control systems
- goal-directed behaviour
- conflict monitoring
goal-directed behaviour
lateral prefrontal cortex, frontal pole
Maintenance of goals in working memory
* Filtering of information according to goals, and
goal-dependent initiation, inhibition, and
shifting of behavior
* Planning and organization of multiple goals of
different complexity
conflict monitoring
Medial PFC (incl. anterior cingulate cortex [ACC])
* Monitoring of goal achievement (error
detection, negative feedback, response conflict,
surprise)
* Modulation of the degree and allocation of
cognitive control
cognitive control deficits after PFC lesions
No directly obvious impairments of perception, language, long-term memory, or motor skills.
* Complex, idiosyncratic impairments in goal-directed initiation, inhibition, and shifting of behavior (great difficulties in managing daily life), e.g.:
* Perseveration (persisting in a response even after being told that it is incorrect).
* Apathy, distractibility, impulsivity.
* Inability to make decisions, plan actions, understand consequences of actions, follow rules.
* Disregard social conventions, are socially inappropriate.
environmental dependency syndrome
Stimulus-driven behavior: actions guided
not by the patient’s own goals but by
what is available in the immediate
surrounding environment
* Imitation behavior: for example,
imitating the physician (hand gestures,
body postures, drawing, combing hair,
chewing on a pencil, speaking, singing,
etc.)
* Utilization behavior: abnormal reliance
on environmental stimuli to trigger
behavior (e.g., repeatedly drinking from a
glass without being thirsty)
relative PFC size does not explain human cognition
Only absolute PFC size is larger in
humans than in non-human primates
but proportions are similar across
primates
but greater relative PFC white matter volume (axonal connections) in human PFC compared to other primates
delayed-response task
Require to retain a stimulus attribute (e.g.,
location) not currently present in the
environment ”in mind” over a delay period
* Performance on delayed-response tasks is
impaired by PFC lesions
* In associative-memory control task, reward is
paired with a cue (long-term memory
association)
* Performance on the associative-memory
control task is not impaired by PFC lesions
* Delayed-response tasks are widely used to
study the neural bases of working memory
delay-period activity
Oculomotor delayed response (ODR) task: keep spatial location (cue) in mind to direct a later eye movement (response)
* Lateral PFC neurons fire continuously during delay
(between cue and response) period for their preferred location
* Delay-period activity also for various other memorized stimulus attributes and other response modalitiesSuccessive memorization of two
stimulus attributes: first identity, second location
* Some lateral PFC neurons retain identity information, others location information, and others
both
* Task-specific selectivity of lateral
PFC neurons
* Flexibility: when task changes, these neurons can retain information about different stimulus attributes
* Suggests that these neurons represent task goals rather than task-relevant information per se
integrative model of goal-directed processing
Lateral PFC: sustained representation of task goal
* Posterior cortex (higher-level sensory areas):
representation of task-relevant information (e.g., stimulus
representations and knowledge in long-term memory)
Selection of task-relevant information: Dynamic
filtering
- Lateral PFC: selection of different types of information
according to dynamic goals (attentional mechanism) in posterior cortex - Posterior cortex (higher-level sensory areas): inhibition
of task-irrelevant and enhancement of task-relevant
information
dynamic filtering
Attentional selection: Enhancement and
suppression
* Task goals modulate posterior cortex: fMRI activity in
category-selective higher-level visual cortex
* Category-specific enhancement of task-relevant
information and suppression of task-irrelevant
information (relative to passive viewing)
Role of lateral PFC in attentional selection
* Filtering deficits with lateral PFC lesions: ERPs (P100)
reveal reduced suppression of unattended tones and
reduced enhancement of attended tones
* Repetitive TMS (rTMS) to lateral PFC reduces
attentional modulation of P100 in feature-based
attention task
* Deficits primarily reflect reduced inhibition of
irrelevant information (e.g., larger P100 for
inhibition of action
stop-signal task
- Respond to stimulus but inhibit response
if a stop signal is presented shortly after
the stimulus - Stop signal typically activates (right)
inferior frontal gyrus (similar for failed
and successful stop) - Motor cortex: high initial activation level
in failed stop trials (cannot be stopped
by inferior frontal gyrus anymore) - Similar to inferior frontal: preSMA in
medial frontal cortex and basal ganglia
(subthalamic nucleus STN) - Aborting of response is carried out via
pathway from inferior frontal to STN
action hierarchy
Making plans to organize actions
* A hierarchy of subgoals leading to a goal
* Planning: anticipation of consequences,
requirements for achieving subgoals
* Impaired in patients with PFC lesions
prefrontal cortex hierarchy
Posterior-to anterior gradient in PFC related to
the complexity/level of abstraction of action
goals
fMRI study with 4 nested tasks that increased in
complexity/level of abstraction:
A. Response competition: variation of the number
of possible finger responses to colors (1–4)
B. Feature task: response based on texture, colors
indicate texture-response mapping
C. Dimension task: colors indicate the dimension
on which stimuli should be judged
D. Context task: same as dimension task, but color-
to-dimension mapping changes from block to
block
Shift from posterior premotor regions (A, B) to
more anterior inferior frontal (C) and frontal pole (D)
Error detection and negative feedback
ERP components linked to medial prefrontal cortex
(ACC)
* Error-related negativity follows incorrect responses
* Feedback-related negativity follows feedback about errors
* Signals from ACC could be sent to lateral PFC to reactivate
the goal in working memory
Predicting errors from fMRI activity
* Activity in the cognitive control network
(medial and lateral PFC): steady decrease
before an error
Predicting errors from fMRI activity
* Activity in the cognitive control network
(medial and lateral PFC): steady decrease
before an error
* Activity in the default mode network
(precuneus, concerned with self-referential
thinking): steady increase before an error
* Continuous shift from cognitive control to
default mode network until an error is made
(and then the shift reverses)
Problems with the error detection
hypothesis
* Could partially reflect surprise (unexpected)
* ACC activity is also observed in tasks where
errors are rare, but that induce conflict
conflict monitoring in the stroop task
Response conflict in the Stroop task
* Irrelevant words automatically evoke a
response that can interfere with producing
the correct ink name (in incongruent trials)* Incongruent trials (conflict) evoke activity in
ACC
* ACC activity (and response times) are greater
when the previous trial is congruent rather
than incongruent (more conflict, more need
for monitoring)
* Increased activity in ACC results in increased
activity in lateral PFC in the next trial →
Conflict monitoring reactivates the goal in
working memory
posterior-to-anterior hierarchy in ACC
Similar to posterior-to-anterior hierarchy in
lateral prefrontal cortex
* In ACC control of conflict between:
▪ Posterior: potential motor responses
▪ Middle: possible response options
▪ Anterior: possible response strategies
* Topographical functional connectivity
between ACC and lateral PFC in resting-state
fMRI
* Suggests a specific signal from ACC to lateral
PFC calling for greater goal activation
