Development of cognitive control Flashcards
Prefrontal cortex
Four main subdivisions
Lateral
Ventromedial
Frontal pole
medial frontal
System I: Goal-oriented behavior
LPFC and FP working in more posterior cortical regions
memory system
recruits taskrelevant information
Planning, initiating, inhibiting,
shifting
System II: Monitoring and guiding behavior
MFC working in tandem with
with other PFC areas
Monitors ongoing activity
Modulates cognitive control
Detects errors
Allocate attention
Engage-disengage from task
(MFC – default network)
The human PFC is special
Massive connections with
other cortical and subcortical
areas
Half of human frontal lobe
Difference with other
primates mostly white matter
Ontogeny recapitulates
phylogeny
Synaptic pruning
(loss of connections)
use it or lose it principble
Hierarchical Gradient Hypothesis
Premotor cortex: Number of stimulus-response mappings, but stable across trials
Caudal LPFC: Contextual task demands (e.g., respond if color is green, but not
if stimulus appears in white)
Rostral LPFC: Variations in instructions between runs (e.g., rules from run 1
might be reversed in run 2)
Abstractness of goal representations and PFC activation
Level A: Response
Lvl B: Feature
Lvl C; dimension
LVL D: context
Three key transitions in the development of cognitive control
- From perseverating to overcoming habits when directed
- From reactive to proactive cognitive control
- From externally driven to self-directed cognitive control
PFC sub-regions with processing sensitivity
Ventrolateral PFC
* Maintenance & storage of information
Dorsolateral PFC
* Manipulation of information
Adult age-related changes in cognitive functions
Episodic memory
Slower processing speed
More susceptible to interference
Cognitive Control
* Goal-related behavior
* 3 factors: updating, inhibition
& shifting/task switching
Age-related changes at the brain level: Brain structure
Volume decreases
White-matter myelination decreases
Connectivity (e.g., default network and its disengagement)
Age-related changes at the brain level: Neural activity
Decrease (older < younger): cognitive deficits?
Increase (older > younger): compensatory or dedifferentiation?
Same (older = younger): same levels of performance?
Age-related changes at the brain level: Neurotransmitters
Many changes first linear, but become non-linear (accelerate)
in the 6th decade of life
Increase in CSF (ventricle size)
Decrease in grey matter volume by up to 25% between ages
20 and 80 (shrinkage of cell bodies rather than cell death)
White-matter volume remains relatively constant; however,
density decreases and microstructure changes
Reductions in neurotransmitter binding potential and receptor
density for dopamine and serotonin
Anterior-posterior gradient: (pre-)frontal regions show more rapid age-related decline than parietal and occipital regions and start to decline at a younger age
Cognitive control and the prefrontal theory of ageing
Cognitive control is the most affected
Prefrontal regions show the earliest and fastest decline
The more cognitive control processes are involved in a task, the larger the expected difference between older and
younger adults.
General switch costs
= mixed - single
→ Maintanenance and selection of task
