Psychiatric Dysfunction: Executive Function Flashcards
(12 cards)
Tripartite model of executive function. 3 components
Working memory - holding and mental working with information in mind
Inhibitory control - Resisting temptations, not acting impulsively and overriding automatic behaviour
Cogntive flexibility - Fluidly changing perspectives or approaches to solving a problem, adjusting to new demands, switching between priorities or tasks
Working memory test
digit spans, pointing spans, remembering digits or directions
inhibitory control test
Stroop: saying colour of word
Flanker: identifying the direction, colour, or letter in middle regardless of things on side
Cognitive flexibility test
Wisonsin card sort: criteria to sort cards changes
Trail making with alteration: alternating between consecutive numbers or letters
Orbitofrontal subdivision
Controls impulses, inhibtiing inappropriate actions
Dorsolateral (top of front side of brain)
Keeps focus, allowing multi tasking planning
Damage to orbitofrontal lobe
Impulsive, socially inappropriate, poor safety judgment, difficulty evaluating anticipated consequences, don’t learn from mistakes due to diminished guilt/regret
Damage to dorsolateral lobe
Distractible, disorganized, preservative, difficulty multitasking, poor time management and prioritization
Key symptoms of ADHD
Extreme inattention, hyperactivity, impulsivity
Neurobiology of ADHD
Reduced activity and volume of PFC. Slower maturaion of PFC. Normal cortical thinning is slower (related with hyperactivity/impulsivity)
ADHD subjects do not have orbitofrontal activity when withholding a response
Dual-pathway model
Executive circuit (dysfunction: inattention) - dorsolateral
Reward circuit (dysfunction: lack of motivation) - orbitofrontal
Evidence of a hypoactive dopamine system
Major treatments
Medications that act upon dopamine and norepinephrine systems in PFC and subcortical structures
