SUMMATION OF RESPONSE RATES TO DISCRIMINATIVE STIMULI ASSOCIATED WITH QUALITATIVELY DIFFERENT REINFORCERS¹

Abstract

In Experiment I, a four-ply multiple schedule was used to study the effects on rate of responding in rats of food, water, and food and/or water reinforcement under different deprivation conditions. Food and water were associated separately with different stimuli, the combination of which was associated with food and water together, or with food or water randomly. Rates in the presence of the combined stimuli were consistently intermediate to the rates generated by the separate stimuli, a result seemingly incompatible with a "summation" hypothesis. Experiment II was a simplified systematic replication of Experiment I, verifying the major findings.

The Integration of Habits Maintained by Food and Water Reinforcement Through Stimulus Compounding

“…Results of Experiment 2 demonstrated additive summation for the first time when freeoperant responding was maintained in one of the compounded stimuli with water and in the other with food. This finding conflicts with those of Lawson et al (1968) who concluded that summation is not forthcoming when stimuli associated with qualitatively different reinforcers are compounded. However, a procedural comparison of that study and Experiment 2 may have identified the training variables relevant to response enhancement during stim-ulus compounding and thus the basis of the different outcomes of Experiment 2 and the experiments of Lawson et al…”

Modification of ethanol’s reinforcing effectiveness in rhesus monkeys by cocaine, flunitrazepam, or gamma-hydroxybutyrate

“…These results are similar to some research conducted with food and water reinforcers in which summation of the reinforcing functions of a food + water combination was not obtained. For example, Lawson et al (1968) reported that food maintained high rates of responding in rats and water maintained responding at lower rates. When a food + water combination was available contingent upon responding, intermediate response rates emerged.…”

Efectos De La Demora De Reforzamiento Sobre Las Respuestas Mantenidas Con Reforzadores Constantes Y Cualitativamente Variados

“…Además del estudio de Roca et al (2011) y de Lawson et al (1968) existen algunos estudios con participantes humanos en los cuales el reforzamiento cualitativamente variado no resultó en un mayor número de respuestas que el reforzamiento constante (Bowman, Piazza, Fisher, Hagopian, & Kogan, 1997;Koehler, Iwata, Roscoe, Rolider, & O'Steen, 2005). En estos estudios se emplearon programas concurrentes de reforzamiento y no se encontró una preferencia sistemática por la opción de respuesta que resultaba en reforzadores variados respecto a una opción que resultaba en reforzadores constantes.…”

“…En resumen, el efecto aditivo del reforzamiento variado sobre la tasa de respuesta no ha sido sistemático: en algunas investigaciones se ha encontrado que el reforzamiento cualitativamente variado mantiene tasas de respuesta más altas relativo al reforzamiento constante (Egel, 1980(Egel, , 1981Milo et al, 2010;Steinman, 1968aSteinman, , 1968b, mientras que en otras no ha sido posible replicar tales resultados (Bowman et al, 1997;Koehler et al, 2005;Roca et al, 2011). Además, se han encontrado inconsistencias en la literatura respecto a las variaciones cualitativas de los reforzadores y la resistencia al cambio (Lawson et al, 1968;Milo et al, 2010).…”