Reading focus
Syllabus: How Does Substance Use Become Persistent Despite Harm?
Compare the reward and avoidance tasks and the alternative explanations for continued responding.
Why you’re reading it. Test whether a laboratory pattern warrants a habit interpretation and a claim about persistent substance use.
A question to consider. What would you measure to distinguish stronger habitual control from incomplete knowledge of the changed outcome?
Why this reading
An explanation in terms of habit requires evidence beyond frequent repetition. Ersche and colleagues compare responses to changed outcomes in people with cocaine dependence and controls. Their contrasting reward and avoidance tasks make it possible to examine how a laboratory measure acquires its theoretical meaning.
Before you read
Goal-directed responding depends on knowledge of an action’s outcome and its current value. Outcome devaluation changes that value. Continued responding can suggest habit, but learning, memory, motivation and understanding of the task also matter. Negative reinforcement involves avoiding or removing an aversive event; it is not punishment.
Read for
- Compare what participants learned and how outcomes were devalued in the reward and avoidance tasks.
- Separate reduced learning accuracy, responses to devalued outcomes and the statistical control for executive performance.
- Inspect the different results across tasks before treating them as one general inability to respond to consequences.
Consider afterwards
- How could poor knowledge of the task produce behavior that looks habitual? Design a comparison that addresses that explanation.
- What further evidence would be needed to carry the task findings into a claim about a particular treatment?
Editorial context
The study compared 72 actively using participants with cocaine dependence and 53 controls. It tested symbolic rewards and shock avoidance, not choices about cocaine or a treatment programme. Group differences cannot establish whether cocaine caused the learning pattern. Hogarth’s later critique questions whether impaired task knowledge can explain apparent habit effects. The article’s broad treatment conclusions go beyond a direct treatment test.