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The aim of this paper was to explore the effect of varying the spatial distance between the liquid dispenser and the light-lever set on spatial location and response rate in rats. Based on the logic of temporally defined schedules, an experiment was designed in which a spatial property of the stimuli (distance) was manipulated while the temporal properties remained relatively stable. Group 1 was exposed to 3 phases in which the distance between the liquid dispenser and the light-lever set increased. Group 2 was exposed to similar conditions, but the spatial distance decreased as the phases progressed. T cycle length was 30 s and the probability of reinforcement was 1. The reinforcer (water) was delivered at the end of the cycle. The subjects were 8 female Wistar rats. Extended conditioning chambers were used in which the stimulation devices could be placed in different locations. Results showed that rats stayed longer in the zone near the liquid dispenser even after it changed location. Also, the response rate showed low levels for all rats throughout the experiment; however, this was a function of spatial contiguity. Wilcoxon and Mann-Whitney U non-parametric tests were used in the statistical analysis. Some spatial properties such as cardinal location or geographic distribution are proposed, which could be studied parametrically and integrated into stimulus schedules. [ABSTRACT FROM AUTHOR]

One study was conducted to evaluate the effects of manipulating the values of P on performance under temporal defined schedules. It was used 6 experimentally naive albino rats that were divided into two groups. Each group was exposed to a temporal defined schedule with different cycle length. Group 1 was T = 30 s., and Group 2 was T = 120 s. Each group was exposed to four distinct experimental phases. The parameter P was manipulated between phases with the values of 1.0, 0.5 and 0.1. The first three phases the subintervals tD and tΔ were signaled differentially. During the phase fourth (redetermination), signaling was eliminated in both subintervals. The results suggest that the T-cycle length determines the response patterns. In addition, differences were observed in temporal properties of effective and ineffective responses under signaling and no signaling conditions. The results were analyzed in terms of type of the behavioral adjustment to occurring contingencies featured into temporal defined schedules. We suggest that this procedure represent a relevant methodological tool for analyzing the contextual and supplementary functions suggested by Ribes and Lopez (1985). [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effects of the variations of water availability through the manipulation of Ť values, under different signaling conditions of subcycles, maintaining constant the water delivery probability (P). Data from this study show that in some rats were observed an increase in the frequency response associated with varying Ť. There were no systematic effects related to signals in subcycles. We analyze the functional difference between P and Ť and its relationship with the frequency and temporal distribution of response. [ABSTRACT FROM AUTHOR]