Cocaine and food deprivation: effects on food-reinforced fixed-ratio performance in pigeons.
Food deprivation level decides how quickly pigeons stop noticing cocaine’s hit on reinforced key pecks.
01Research in Context
What this study did
Scientists gave pigeons cocaine before their daily key-peck session. Birds worked on a fixed-ratio schedule for food.
The team varied two things: cocaine dose and how hungry each bird was. They watched how fast pecking dropped and how quickly tolerance grew.
What they found
Higher cocaine doses cut response rates more. Birds that were kept lean learned to
true
work through the drug faster. Heavier birds took longer to show the same bounce-back.
How this fits with other research
Hus et al. (2013) later showed tolerance can form even when a dose never slows responding. E et al. found the same drug, but hunger—not prior disruption—set the speed.
Meyer et al. (1987) proved ratio size matters: big FR schedules block tolerance. The 1996 paper adds hunger as a second dial you can turn.
Lerner et al. (2012) repeated the pattern in a memory task. Cocaine hurt accuracy at first, then tolerance returned. Same drug, same species, same story—different operant task.
Why it matters
For BCBAs, the lesson is that motivation level changes how fast an organism adapts to any suppressive event—drug or otherwise. If a client’s responding tanks after a new med, tighter food or token deprivation may speed recovery of baseline. Always track body weight or reinforcer access when you chart behavior during medical changes.
Get CEUs on This Topic — Free
The ABA Clubhouse has 60+ on-demand CEUs including ethics, supervision, and clinical topics like this one. Plus a new live CEU every Wednesday.
Graph each learner’s weight alongside daily response rate; note if dips recover faster on leaner days.
02At a glance
03Original abstract
Key pecking by 6 pigeons was maintained by a fixed-ratio 30 schedule of food presentation while body weights were 80% of free-feeding weights. Acute administration of cocaine (0.3 to 13.0 mg/kg, i.m.) dose-dependently decreased response rates. Dose-effect curves were shifted to the right when 3 of the 6 pigeons were maintained at 70% of free-feeding weights and were shifted to the left when the other 3 pigeons were maintained at 90% of free-feeding weights. Then a dose of cocaine that initially decreased response rates by more than 95% of control rates was administered before each daily session. Comparable degrees of tolerance to these rate-decreasing effects developed in the two groups. The rate at which responding recovered was relatively rapid for pigeons in the 70% free-feeding-weight group and was slower for 2 of the 3 pigeons in the 90% free-feeding-weight group. When body weights were then increased from 70% to 80% or were decreased from 90% to 80% of free-feeding weight, performance was disrupted initially only for pigeons whose weight went from 70% to 80% of free feeding. In the present experiment the degree of deprivation may have indirectly influenced the degree of tolerance that developed to cocaine's response rate-decreasing effects because it directly influenced the dose chosen to be administered chronically. The degree of deprivation appeared to have a more direct influence on the rate at which tolerance developed.
Journal of the experimental analysis of behavior, 1996 · doi:10.1901/jeab.1996.65-145