Sequential dependencies of the lengths of consecutive response runs.
Response runs form predictable chains that fall apart when reinforcement stops.
01Research in Context
What this study did
Mechner (1958) watched rats press levers for food. The team recorded how long each run of presses lasted before the rat paused.
They looked at whether the length of one run predicted the length of the next run. They also watched what happened when the food stopped.
What they found
Run lengths were not random. A short run tended to follow another short run. A long run tended to follow another long run.
When food ended, the pattern broke down. The rats' runs became more variable.
How this fits with other research
Hachiga et al. (2010) later showed you can wipe out these same sequential patterns. They paid rats only when run lengths looked random. The dependencies disappeared.
Macdonall (1998) extended the idea to concurrent schedules. Run lengths still tracked the payoff ratio, proving the pattern is under environmental control.
KELLEHER et al. (1963) added kids to the story. More continuous reinforcement before extinction made the later burst bigger and more variable in both rats and children, echoing the 1958 jump in variability.
Why it matters
The study tells you that even simple repeated actions leave a footprint. The next response is shaped by the last. When you see a client stick to a rigid routine, remember it may be a string of short runs feeding each other. Break the chain early with differential reinforcement, just as Yosuke's team did, before the pattern hardens.
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Join Free →Count the client's last three response runs; if you see a repeating length, change the payoff rule to break the streak.
02At a glance
03Original abstract
Three male albino rats, working under thirst drive in two-lever Skinner boxes, were trained under a procedure in which the reinforcement requirement was a minimum of eight consecutive responses on lever A followed by a response on lever B. The following aspects of the resulting performance were investigated: a.) sequential dependencies of the lengths of consecutive runs; b.) cyclic fluctuations in the length of successive runs; and c.) run-length changes during extinction. It was demonstrated that the length of a run is related to the length of the immediately preceding run, that there sometimes appear cyclic fluctuations in the length of successive runs, and that run-length variability increases under conditions of extinction.
Journal of the experimental analysis of behavior, 1958 · doi:10.1901/jeab.1958.1-229