Drug discrimination using a conditioned taste-aversion paradigm in rhesus monkeys.

Ferrari et al. (1991) worked with rhesus monkeys. The monkeys pressed a lever for food on a fixed-ratio schedule.

Before each session the monkeys got a taste of alprazolam. After the session they got either lithium or amphetamine. The team wanted to see if the drug taste alone could later control the monkeys’ lever pressing.

Alprazolam first slowed the monkeys’ responses. After several pairings, the taste of alprazolam by itself changed how the monkeys responded. The drug cue became a signal that predicted the bad after-effect, so the monkeys adjusted their pressing when they tasted it.

Sobsey et al. (1983) showed the same idea in pigeons. A light paired with postsession amphetamine stopped the birds from pecking. The 1991 monkey study moves the idea from simple suppression to full drug discrimination.

Fyfe et al. (2007) later used the same principle in adults with intellectual disabilities. A green card paired with punishment stopped stereotypic behavior. Together these papers show that a brief stimulus paired with any bad outcome—drug or punishment—can gain fast control across species.

Stretch et al. (1966) found that methylphenidate can wreck stimulus control at high doses. The 1991 paper agrees: alprazolam first disrupts rate, then the taste itself becomes the new controlling cue. The early rat warning still holds when the drug becomes its own signal.

You can turn any brief stimulus into a powerful cue just by pairing it with a bad consequence that happens later. For clients who self-administer edibles or liquid meds, a unique flavor paired with a mild consequence (timeout, brief restraint) could teach them to refuse the substance when they taste it again. Start with one clear flavor, deliver the outcome after the session, and track the first sign of suppression—that’s your new discrimination baseline.