Background 4 Flashcards
3 biases to drugs
- approach bias
- memory bias
- attentional bias
according to the dual-process account of CBM, these biases are driven by…
According to the dual-process account of CBM, these biases are driven by (bottom-up) mental associations (Pavlovian and/or instrumental), and their effect is moderated by (top-down) executive control processes.
Alternatively, according to the inferential account proposed recently by Wiers and colleagues (2020)….
the effectiveness of CBM depends on inferential processes
relapse rates of CBT
50% relapses within 6 months, 70% within 3 years.
approach bias =
the tendency to approach appetitive stimuli.
with what task can approach bias be investigated
approach-avoidance task (AAT).
uitleg van approach-avoidance task
For example, pictures of alcoholic and non-alcoholic drinks are shown on the computer screen. Sometimes the images are tilted to the right and sometimes to the left. Based on this ‘irrelevant feature’ (the direction in which the image is tilted), participants are instructed to pull a joystick towards them (approach response: in this case, the image becomes larger) or to push it away (avoidance response: in this case, the image becomes smaller). For example: right tilt means approach, and left tilt avoid. The purpose of the ‘zooming feature’ (with pictures becoming larger or smaller depending on the response) functions to generate a strong sense of approach and avoidance. The alcoholic and soft drinks are depicted equally often with a tilt to the right and to the left. A faster reaction time when drawing the alcoholic drinks towards you then when pushing it away would be interpreted here as an approach bias. The soft drinks in this example serve as a control or baseline to determine whether the approach bias to alcoholic drinks is stronger than to non-alcoholic drinks.
attention bias =
selective attention that addicts have for drug-associated stimuli.
how to measure attention bias
dot-probe task
dot-probe task uitleg
In this test, subjects are presented with two stimuli, e.g. a drug-related one and a neutral one. Then one of the two stimuli is replaced with a specific stimulus to which the subject must respond (e.g.: “do you see 1 or 2 dots?”). A shorter response time to a stimulus that replaces a substance-related cue (as opposed to a neutral cue) is interpreted here as a attentional bias for substance-related peripheral stimuli.
how can we measure memory bias
Automatically activated memory associations can be measured with the Implicit Association Task (IAT). This is a categorization task in which the subject has to categorize words or pictures into 2 x 2 categories with a left and right button. For example: pictures of drinks should be categorized by nonalcoholic (left) versus alcoholic (right), and active versus passive (arousal dimension). If subjects respond more quickly when alcohol and ‘active’ share a button (and thus non-alcoholic drinks and passive share the other button), than when the categories are divided over the buttons the opposite way, this would indicate that they associate alcohol with high arousal. Or alternatively, the categories could be evaluative (positive versus negative).
verschil proof-of-principle en RCTS
When reviewing the evidence for the effectiveness of CBM it is crucial to distinguish between experimental proof-of-principle studies and clinical studies. Proof-of-principle studies are typically conducted in the lab to reveal psychological mechanisms underlying human behavior in the lab (usually in healthy volunteers). In contrast, randomized controlled trials (RCTs) are conducted in a clinical setting with patients, to test the efficacy of an intervention in a clinical sample. In RCT’s, the effect of a treatment (intervention) is compared with that of a control treatment (either another treatment or placebo), and patients are randomly assigned to the experimental and control groups. RCT’s are generally considered the gold standard for testing the effectiveness of a treatment.
Wiers, Boffo and Field (2018) reviewed the evidence for the effectiveness of CBM interventions for alcohol use disorders. They distinguished between (1) proof-of-principle studies, (2a) online studies in which self-identified problem drinkers receive CBM as a stand-alone intervention, and (2b) RCT’s in which CBM is added to treatment as usual of alcohol-dependent patients.
what did they conclude?
They concluded that proof-of-principle studies are important, because these provide the basis for clinical trials, but that CBM tends to have only small, short-lived effects on drinking in student volunteers, that are not clinically relevant. However, clinical trials show that CBM does hold promise as an add-on intervention to treatment of alcohol-dependent patients. There are many differences between proof-of-principle studies and clinical trials that could explain the slight divergence in findings, but the most important are: motivation for change, standalone or addition, awareness of getting an intervention, treatment goals (abstinence or reduction?)
opponent process theory=
says that when addiction tolerance develops, drugs are taken to avoid negative withdrawl symptoms (negative reinforcement)
(but newer theories state that the withdrawal symptoms are not as important -> becasue relapse often occurs after withdrawal symptoms have dissapeared)
