Human and pigeon suboptimal choice

Abstract

Many studies have shown that pigeons will sometimes behave suboptimally by choosing an option that provides food less frequently over one that provides food more frequently. The critical factor in driving suboptimal behavior in these procedures is that the delayed outcomes are differentially signaled on the suboptimal alternative, but not the optimal alternative. Although this procedure is frequently cited as potentially analogous to human gambling, there is little empirical data to evaluate this assertion. The present study tested both pigeon (Experiment 1) and human (Experiment 2) subjects with a suboptimal choice task. Subjects chose between a suboptimal alternative that provided a large reinforcer 20% of the time and an optimal alternative that always provided a small reinforcer. Stimuli presented during the delays signaled the outcomes on the suboptimal alternative in some conditions. When outcomes were signaled, pigeons chose the suboptimal alternative more frequently than did humans. When the outcomes were not signaled, pigeons' choices became more optimal, but humans' choices did not. Humans' suboptimal choice was unrelated to performance on a probability discounting task. Overall, these findings suggest that although both pigeons and humans can choose suboptimally, more research is needed in order to determine whether non-human performance on this task can serve as a model for human gambling.

Human Choice Predicted by Obtained Reinforcers, Not by Reinforcement Predictors

“…Interestingly, dogs and rats showed no such preference ( Jackson et al, 2020 ). The absence of a preference for predictive stimuli from dogs and sometimes from rats ( Jackson et al, 2020 ) is similar to the present studies’ findings as well as those from McDevitt et al (2019) with human participants.…”

“…Perhaps most interesting is that reinforcement predictors seemed to play no role in adult human choice behavior within the scope of this task, which is different than what has been found in pigeons ( Stagner and Zentall, 2010 ). Similar results were found recently with adult human participants in that they also did not show any preference for reinforcement predictors ( McDevitt et al, 2019 ). A closer look at the present results illuminates that adult human choice in this task was driven by reinforcement history rather than reinforcement predictors.…”

“…When comparing the absence of a preference for reinforcement predictors from adult humans in the present studies as well as McDevitt et al (2019) to that of developmentally delayed children, a clear difference can be observed in choice behavior. That is, adult humans do not show a preference for predictive stimuli ( McDevitt et al, 2019 ) but, under certain conditions, developmentally delayed children do ( Lalli et al, 2000 ). When given a similar two-alternative task, rhesus macaques ( Smith et al, 2017 ) showed a similar preference to that of developmentally delayed children ( Lalli et al, 2000 ).…”

“…Recently, McDevitt et al (2019) attempted to replicate previous findings in pigeons and adult humans using a two-alternative task. While pigeons performed similarly to past studies in that they preferred a suboptimal alternative that produced reinforcement-predictive stimuli, adult human participants showed no such preference ( McDevitt et al, 2019 ). Specifically, adult human participants demonstrated a clear preference for an optimal alternative that did not produce predictive stimuli.…”

“…Specifically, adult human participants demonstrated a clear preference for an optimal alternative that did not produce predictive stimuli. When an unsignaled condition was employed in which neither alternative produced predictive stimuli, adult human participants also chose the optimal alternative ( McDevitt et al, 2019 ). Interestingly, these results are similar to those found by Molet et al (2012) with adult human participants, but contrasts with results from developmentally delayed children ( Lalli et al, 2000 ), rhesus macaques ( Smith et al, 2017 ), rats ( Chow et al, 2017; Cunningham and Shahan , 2019 ), and pigeons ( Stagner and Zentall, 2010 ; Zentall and Stagner, 2011 ).…”