RESISTANCE TO CHANGE AS A FUNCTION OF STIMULUS-REINFORCER AND LOCATION-REINFORCER CONTINGENCIES

Pigeons responded on two keys in each component of a multiple concurre nt schedule. In one series of conditions the distribution of reinforce rs between keys within one component was varied so as to produce chang es in ratios of reinforcer totals for key locations when summed across components. In a second series, reinforcer allocation between compone nts was varied so as to produce changes in ratios of reinforcer totals for components, summed across key locations. In each condition, resis tance to change was assessed by presenting response-independent reinfo rcers during intercomponent blackouts and (for the first series) by ex tinction of responding on both keys in both components. Resistance to change for response totals within a component was always greater for t he component with the larger total reinforcer rate. However, resistanc e to change for response totals at a key location was not a positive f unction of total reinforcement for pecking that key; indeed, relative resistance to extinction for the two locations showed a weak negative relation to ratios of reinforcer totals for key location. These result s confirm the determination of resistance to change by stimulus-reinfo rcer contingencies.