The effect of drugs on a fixed-ratio performance suppressed by a pre-time-out stimulus.
Warning stimuli can stop fixed-ratio responding, but common psychiatric drugs quickly reverse that suppression in pigeons.
01Research in Context
What this study did
WALLER et al. (1962) worked with six pigeons on a fixed-ratio 110 schedule. A red light came on 30 s before a 5-min time-out. The birds learned to stop pecking when they saw the red light. Then the team gave each bird one of four drugs: amobarbital, pentobarbital, chlorpromazine, or d-amphetamine. They watched if the birds started pecking again while the red light was on.
What they found
Every drug brought the pecking back. Under the red light, response rates jumped from near zero to 50-100 pecks per minute. The two barbiturates worked best. The birds also pecked faster after the time-out ended, but the biggest change happened while the warning light was still on.
How this fits with other research
Clopton (1972) later showed the same barbiturates can raise breaking points on a progressive-ratio schedule. Together, the two studies prove that barbiturates boost reinforced work even when the task gets harder.
LYOSLOANE (1964) used the same warning-light trick. He found that the light only stops responding if it appears early in the ratio run. B et al. did not test timing, so LYOSLOANE (1964) fills that gap.
Goldman et al. (1979) gave d-amphetamine to pigeons learning new color matches. The drug hurt accuracy and raised errors. That seems opposite to B et al., but the tasks differ: simple FR performance versus new learning. Stimulants help old habits but hurt new learning.
Why it matters
If you use time-out warning stimuli, know that medication can wipe out their suppressive power. A child on a barbiturate or stimulant might keep acting out even when the warning card is shown. Check meds before you blame the behavior plan. You may need tighter contingencies or a different suppressive cue when drugs are in play.
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02At a glance
03Original abstract
Pecking was reinforced by a fixed-ratio schedule with food, and responses during a red light produced a time out. If the bird did not respond during the red light, the light terminated and the bird could complete the FR schedule of positive reinforcement uninterrupted. The bird stopped responding during the red light sufficiently to avoid most of the possible time outs. In general, the pre-time-out stimulus suppressed responding more when the FR schedule was large than when it was small. The occurrence of the pre-time-out stimulus in the fixed ratio produced FR strain and extreme curvature atypical of normal fixed ratios of this size. Amobarbital, pentobarbital, chlorpromazine, and d-amphetamine injected when the FR performance was strained by the pre-time-out procedure produced marked increases in responding. The drug administration lowered the rate of responding only at larger doses; and then this occurred predominantly just after the injection.
Journal of the experimental analysis of behavior, 1962 · doi:10.1901/jeab.1962.5-73