Executive functions in addiction Flashcards
verschillende soorten executive functions
- Error monitoring: detecting erroneous (wrong) responses.
- Working memory: maintaining and manipulating information in memory.
- Cognitive flexibility / set shifting: shifting attention between one task and another.
- Decision making: basing choices on the advantages, costs, and risks associated with behavior.
- Inhibitory (impulse) control: inhibiting actions and thoughts.
prefrontal cortex heeft invloed op
executive functions
waar zijn executive control deficits vaak aan gerelateerd (brain regions)
dysfunction of the PFC, anterior cingulate and orbitofrontal cortex
verschillen in het fysieke brein geassocieerd met substance abuse
- grey matter volume reductions in PFC, cingulate cortex and insula.
- white matter alterations
Gray and white matter alterations appear to be a risk factor of substance use, but also appear to be affected by it. These alterations may partially mediate cognitive dysfunction in addiction.
grey matter volume reductions: argument voor cause en argument voor consequence
- Consequence: PFC gray matter volume gradually decreases in people with alcohol and morphine addiction but these deficits can also decrease after a period of abstinence.
- Risk factor: non-abusing individuals with family histories of substance abuse have been show to have gray-matter reductions.
wisconsin card sorting test=
meet cognitive flexibility.
its a research paradigm in which participants need to match cards, without being told how to match them (colour, number, shapes, etc). They are given feedback on whether the match is correct or incorrect after each match. The card sorting rule is changed regularly and unannounced.
wisconsin card sorting test in addiction
individuals with a history of substance abuse tend to make perseverative errors (failure to change the rule), indicating a lakc of cognitive flexibility
dus welke testen meten cognitive flexibility
wisconsin card sorting test
welke testen meten decision making
- delay discounting
- iowa gambling task
delay discounting =
the degree to which a reward decreases in subjective value as a function of the time that one has to wait for it. In the delay discounting test, participants are given various choices (usually between monetary rewards; do you want €100 tomorrow or €101 after 31 days?).
-> In individuals with addiction, there is a higher degree of discounting. dus reward decreases faster in subjective value for addiction (lijn gaat stijler naar de 0)
iowa gambling task =
a task that involves decision making on the basis of positive vs. negative consequences. Participants choose cards from 4 virtual decks and are told that each time they can win or lose some game money. They have to discover which decks are advantageous (in the long-term) and which are not:
- Advantageous: 2 decks that give small gains (€50) but also small occasional penalties (€50).
- Disadvantageous: 2 decks that give large gains (€100) but even larger penalties (€250).
-> Most healthy participants learn to stick to the advantageous deck eventually, while patients with mOFC and vmPFC dysfunction and those with addiction tend to perseverate on the bad decks.
hoe kunnen we die decision making in treatment gebruiken
In treatment, one can attach immediate positive consequences to desired behavior to take addict’s deficits in declining immediate gratification over long-term goals into account. This is done in contingency management and is supported by a lot of empirical evidence.
Contingency management = a type of behavioral therapy in which individuals are reinforced (getting vouchers for submission of drug-negative urine) for positive behavioral change.
met welke tasks meten we inhibitory control
- go/no-go task
- stop-signal task
- stroop task
go/no-go task=
= a task in which participants need to respond as fast as possible to ‘go signals’ (heart) but not respond to ‘no-go signals’ (circle).
-> Those with addiction more often fail to suppress responses to ‘no-go signals’
stop-signal task (SST)=
a task in which a cue (indicating to press a button) is occasionally followed by a stop signal, in response to which participants have to inhibit the activated response (not press the button). The stop signal is presented at various intervals: the later the stop signal is presented, the more difficult the trial.
-> Those with addiction have a slower reaction time to the stop-signal, leading to failure to inhibit the responses (especially in the harder trials).
