Response-cost punishment with pigeons: Further evidence of response suppression via token loss

Two experiments were conducted to compare choices between sequences of reinforcers in pigeon (Experiment 1) and human (Experiment 2) subjects, using functionally analogous procedures. The subjects made pairwise choices among 3 sequence types, all of which provided the same overall reinforcerment rate, but differed in their temporal patterning. Token reinforcement schedules were used in both experiments and the type of exchange schedule varied across blocks of sessions. Some conditions permitted immediate exchange of tokens for consumable reinforcers (food for pigeons, video access for humans); in other conditions, tokens accumulated and were exchanged for consumable reinforcers only at the end of the sequence. Choice patterns in the immediate-exchange conditions were generally similar across species, with both pigeons and humans preferring sequences with the shortest delay to the initial reinforcer in the series. The results are broadly consistent with models of temporal discounting expanded to include the impact of sequences of delayed reinforcers acting in parallel from the time of the choice. Preferences were less consistent with discounting models in the delayed exchange conditions. Questionnaire data gathered at the end of the experiment were consistent with prior results of questionnaire studies, but showed no straightforward relation to the observed choice patterns, urging caution in the extrapolation of results from one decision-making domain to the other.

Section: Discussionmentioning

confidence: 90%

Saving the Best for Last? A Cross‐species Analysis of Choices Between Reinforcer Sequences

Andrade

Hackenberg

2012

“…Experiments by Hackenberg and his colleagues have found that stimulus lights can serve as effective tokens for pigeons. The stimulus lights exerted strong control over behavior both on single schedules (e.g., Bullock & Hackenberg, ; Raiff, Bullock, & Hackenberg, ) and in choice situations (e.g., Hackenberg & Vaidya, ; Jackson & Hackenberg, ). The present experiments extended this research by examining the effects of tokens on pigeons' behavior in a concurrent VI choice situation.…”

Section: Discussionmentioning

confidence: 99%

Pigeons' Choices With Token Stimuli in Concurrent Variable‐interval Schedules

Mazur

Biondi

2013

Twelve pigeons responded on concurrent variable-interval schedules that delivered token stimuli (stimulus lights for some pigeons, and white circles on the response keys for others). During exchange periods, each token could be exchanged for food on a fixed-ratio 1 schedule. Across conditions, the exchange requirements (number of tokens that had to be earned before they could be exchanged for food) varied between one and four for the two response keys. The main findings were that the pigeons’ response percentages varied as a function of the number of tokens earned at any given moment, and they were determined by both the delays to food and by the number of food deliveries in the exchange periods. In some conditions, tokens had to be earned but were not visible during the variable-interval schedules for one or both keys. When one key had visible tokens and the other did not, the pigeons showed a preference for the key without visible tokens. A model based on the matching law and a hyperbolic delay-discounting equation could account for the main patterns of choice responding, and for how response percentages changed as successive tokens were earned. The results are consistent with the view that the token stimuli served as discriminative stimuli that signaled the current delays to food.

“…To this point, laboratory models have been limited in the ability to produce genuinely suboptimal choice patterns—a prerequisite for a model of gambling. Third, conceptually, the token system utilized in the present research connects to an expanding body of research using token economic systems to explore a range of topics across species and settings, including conditioned reinforcement (Bullock & Hackenberg, 2006; Foster, Hackenberg, & Vaidya, 2001; Tarbox, Ghezzi, & Wilson, 2006), punishment (Pietras & Hackenberg, 2005; Raiff, Bullock, & Hackenberg, 2008), and reinforcer accumulation (Yankelevitz et al, 2008), in addition to impulsive and risky choice (Hackenberg & Vaidya, 2003; Jackson & Hackenberg, 1996; Lagorio & Hackenberg, 2010; Locey et al, 2009; Paulsen et al, 2011; Reed & Martens, 2011). Token systems have a number of distinctive features that make them especially useful in a translational analysis of decision making, including currencies more analogous to monetary‐based economies in human affairs, bringing a wide range of economic variables—income, savings, expenditures, wages, and prices—within reach of an experimental analysis.…”

Section: Discussionmentioning

confidence: 99%

Risky Choice in Pigeons: Preference for Amount Variability Using a Token‐reinforcement System

Lagorio

Hackenberg

2012

Pigeons were given repeated choices between variable and fixed numbers of token reinforcers (stimulus lamps arrayed above the response keys), with each earned token exchangeable for food. The number of tokens provided by the fixed-amount option remained constant within blocks of sessions, but varied parametrically across phases, assuming values of 2, 4, 6, or 8 tokens per choice. The number of tokens provided by the variable-amount option varied between 0 and 12 tokens per choice, arranged according to an exponential or rectangular distribution. In general, the pigeons strongly preferred the variable option when the fixed option provided equal or greater numbers of tokens than the variable amount. Preference for the variable amount decreased only when the alternatives provided widely disparate amounts favoring the fixed amount. When tokens were removed from the experimental context, preference for the variable option was reduced or eliminated, suggesting that the token presentation played a key role in maintaining risk-prone choice patterns. Choice latencies varied inversely with preferences, suggesting that local analyses may provide useful ancillary measures of reinforcer value. Overall, the results indicate that systematic risk sensitivity can be attained with respect to reinforcer amount, and that tokens may be critical in the development of such preferences.