Effects of diazepam on schedule-controlled and schedule-induced behavior under signaled and unsignaled shock.

Hymowitz (1981) gave rats diazepam and watched two things. Would they still press a lever for food when every press also brought mild shock? Would they keep licking a tube between meals, a quirky behavior called adjunctive licking?

Some shocks came with a short tone warning. Others arrived without a cue. The team compared drug days with plain-saline days to see how warning signals changed the drug’s impact.

Diazepam brought lever pressing back. It also made the rats lick more during breaks. Both effects were bigger when the shock was milder and when a tone announced it.

Without the tone, the drug still helped, but the lift was smaller. The result shows that a simple warning signal can shape how an anti-anxiety drug works.

McMillan (1979) seems to tell the opposite story. Caffeine and d-amphetamine cut both lever pressing and adjunctive licking, while diazepam raised them. The clash is real: stimulants suppress punished behavior; benzodiazepines restore it. Same setup, opposite drugs, opposite outcomes.

Rider et al. (1984) extend the signal idea into choice. Rats picked the schedule with the shorter shock warning, backing the view that brief signals are valuable. N’s work adds that diazepam makes those signals even more effective.

Sanders (1969) tested diazepam earlier in cats on a fixed-interval schedule. The drug changed response patterns then, too, showing the effect holds across species and procedures.

If you run punishment or extinction probes, remember that adjunctive behaviors can rebound when anxiety drops. A warning stimulus, even a 2-second beep, can amplify or shrink that rebound. Try adding a brief cue next time you fade in aversives; note if the client’s stereotypy or water-seeking jumps after PRN benzodiazepines. Small signals steer big drug effects.