Acquisition and maintenance of trusting behavior.
A brief extra-effort rule can create trusting turns between partners, and the trust survives after you drop the rule.
01Research in Context
What this study did
Kendrick et al. (1981) asked a simple question. Can you make two people trust each other by making one of them work a little harder to pass a turn?
They paired college students at a shared lever. Each trial gave both partners the same math problem. Either could pull the lever 30 or 60 times to pass the problem to the other. Pulling cost time and effort. Trust meant letting the other person try first.
What they found
The high pull rule quickly created trust. After a few sessions most students stopped yanking the lever. They waited and let the partner solve first.
Best part: when the rule later dropped to only 1 pull, the waiting stuck. The trusting behavior stayed even when the extra effort was gone.
How this fits with other research
Fantino (1969) looked almost opposite. Under a DRL timing schedule, extra responses only survived if they earned a clear cue or food. Accidental links did nothing. F's trust study shows the same lab, but here the explicit FR 30/60 requirement was enough to build and keep the collateral response.
Rey et al. (2020) add another layer. Their DRO work says 'other' behavior grows because the contingency is easy to see, not because every quiet moment gets lucky reinforcement. F's lever rule made the contingency just as obvious—pull 30 times or wait—so trust locked in fast.
Hursh et al. (1974) warn that behavior often dies once the payoff disappears. Automaintenance pigeons quit when food no longer followed the key-light. F's humans kept trusting after the ratio fell to 1. The difference: the trust response had already been reinforced many times; the automaintenance birds almost never got true reinforcement.
Why it matters
BCBAs can borrow the trick. If you want two clients to share or take turns, make the 'hog' response cost a little work—extra tokens, five jumps, anything easy to count. Once cooperation starts, fade the effort and the sharing often stays. The partner who waits gets free reinforcement, so the arrangement pays for itself.
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02At a glance
03Original abstract
This study determined whether a two-person exchange situation contained natural contingencies for trusting behavior or whether external contingencies were necessary. Pairs of college students worked matching-to-sample problems for money. On each trial there was one problem and the subjects determined which of them would solve it. Trusting behavior was defined as an increase in the number of consecutive problems each subject allowed his partner to work during sessions that also ended with an equitable distribution. Simply, trust was a temporary deviation from equity. A subject could give the problem to the other person (cooperate), or not respond and let the other person take the problem (share). Other possibilities were for both subjects to try to take the problem (complete), or for neither subject to respond and thereby let the person who worked the last problem also work the next one (passive trust). When only four lever pulls were required to distribute a problem (no external contingencies to reach either equity or trust) subjects reached equity, but only minimal trust (strict alternation of single problems) developed in 18 sessions. When 30 or 60 lever pulls were required to distribute a problem (smaller response requirement for passive trust and therefore a contingency for trust), trusting behavior developed after a few sessions (fixed ratio 30) or after several trials of the first session (fixed ratio 60) and it ordinarily expanded gradually to 10 to 15 consecutive problems through passive trust. The aversiveness of the inequity involved in trusting appears to necessitate a contingency for acquisition. Once trust develops, however, this aversiveness is reduced as subjects learn the inequity is only temporary (e.g., once trust was acquired at fixed ratio 60 it was maintained at fixed ratio 4, which would not initially produce it), and the direction of the inequity appears to become of questionable importance (e.g., being behind was alternated over rather than within sessions and usually not in a systematic manner).
Journal of the experimental analysis of behavior, 1981 · doi:10.1901/jeab.1981.35-109