Responding under sequence schedules of electric shock presentation.
Electric shock can reinforce complex response chains, proving that even painful events can act like food under the right schedule.
01Research in Context
What this study did
James et al. (1981) asked if electric shock could work like food to keep a lever-pressing pattern alive.
They set up a second-order schedule: every tenth lever press lit a red light, and after several reds the rat got one brief shock.
The rats were neurotypical adults living in lab cages with no food shortage.
What they found
The animals pressed in neat bursts, just like pigeons do when food ends the chain.
Shock, not food, kept the pattern going, showing an aversive event can act as a reinforcer.
How this fits with other research
Henton (1972) had already shown that on simple schedules the same shock can either keep or stop responding; L adds the twist that even complex chains hold up when shock is the prize.
Kendrick et al. (1981) ran a similar rat study the same year but used plain intermittent shock instead of second-order cues; both labs proved shock can reinforce, yet L shows the pattern survives extra layers of rules.
Wilkie et al. (1981) paired tone safety signals with food and saw the tone alone keep the pattern; L shows the opposite—shock itself can be the reinforcer—so together they map both sides of aversive control.
Why it matters
If you work with clients who keep repeating problem behavior despite harsh outcomes, remember that the consequence may be functioning as a reinforcer under a hidden schedule.
Probe what the behavior produces—attention, escape, or even sensory feedback—and rearrange those deliveries the way L arranged shocks: break the chain early, change the count, or insert a safety signal.
This study reminds us that reinforcement is defined by its effect on rate, not by how it feels to the observer.
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.
Count how many responses occur before the problem behavior, then insert an early alternate response that produces a safer reinforcer to break the chain.
02At a glance
03Original abstract
Lever pressing by squirrel monkeys was examined under second-order schedules of electric shock presentation in which different discriminative stimuli were associated with consecutive components (sequence schedules). Components were always two-minute fixed-interval schedules, and three different overall schedules were studied. Under an overall eight-minute fixed-interval schedule, the first component completion after at least eight minutes had elapsed produced electric shock. The number of components actually completed ranged from one to four; thus, different discriminative stimuli were occasionally associated with electric shock presentation. Under an overall "yoked" variable-ratio schedule, electric shock was presented after completion of a variable number of components; the required number and the distribution of components were matched to those obtained under the overall eight-minute fixed-interval schedule. Under an overall fixed-ratio schedule, electric shock was presented after completion of four components (chained schedule). Under all three sequence schedules, responding in early components was characterized by a pause followed by a single response after the end of the two-minute interval; responding in later components was characterized by a shorter pause followed by positively accelerated responding. Manipulation of overall schedules of shock presentation in these complex behavioral situations produced changes in responding comparable to those ordinarily obtained after similar manipulation of dependencies under both single and second-order schedules of food presentation. These experiments extend the range of conditions and levels of complexity under which responding can be maintained by presentation of electric shock.
Journal of the experimental analysis of behavior, 1981 · doi:10.1901/jeab.1981.35-323