A procedure for studying the within-session onset of human drug discrimination.
A button-press guessing game with rising point penalties lets you watch drug effects start in real time.
01Research in Context
What this study did
The team built a simple button-press task for adults.
People had to guess if they got caffeine or a placebo.
Wrong guesses lost points. The losses got bigger as the session went on.
This pushed people to wait until they really felt the drug before answering.
What they found
The data came out smooth and orderly.
Point losses cut down wild guessing.
They could watch the exact minute caffeine effects showed up.
How this fits with other research
Tanguay et al. (1982) did the same idea with pigeons twelve years earlier. They used colored keys and second-order schedules. The bird work proved the concept; K et al. moved it to humans.
Anonymous (1995) ran a follow-up year later. That study compared the button-press method to self-report forms. Both tools worked, but they captured different pieces of the drug effect. Use both if you want the full picture.
Hughes et al. (2022) shows the trend keeps going. Their speeded-up concurrent-chains setup gives within-session data in rats. The 1994 human method and the 2022 rat method share the same goal: fast, fine-grained readouts for drug studies.
Why it matters
If you team up with pharmacologists, this task is a ready-made tool. It needs only a laptop and a point counter. You get clear onset curves without fancy gear. Swap caffeine for any new compound and you can track when the drug first bites.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Add a five-minute guessing round with escalating point loss to your human drug-discrimination prep and plot choices against session time.
02At a glance
03Original abstract
The purpose of the present study was to develop a procedure for measuring the within-session onset of human drug discrimination. During daily sessions, under double-blind conditions, caffeine-abstinent adults ingested a letter-coded capsule containing 178 mg caffeine or placebo. Trials were presented at 30-s intervals, beginning immediately after drug ingestion and continuing for 60 min. On each trial, subjects could guess which of their two letter-coded drugs they had received by pressing a left button (for one drug) or right button (for the other drug); subjects could also press a center "no guess" button instead of guessing. Each trial ended after one button press. After each session, subjects were told which drug they had received. Subjects earned one point (worth $0.10 per point) for each correct guess. Subjects lost either 0, 1, or 10 points for each incorrect guess; the point-loss contingencies were varied in random order across sessions. Discrimination earnings accumulated across all sessions. The point-loss contingencies decreased random responding and delayed the discrimination time course. Overall, this procedure provided an orderly and relatively continuous measure of the within-session onset of drug discrimination and should have a range of applications in understanding the human behavioral pharmacology of drugs.
Journal of the experimental analysis of behavior, 1994 · doi:10.1901/jeab.1994.61-181