Sistema Regional de Información
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The purpose of this study was to determine the effect of lengthening the duration of a water reinforcement delay on the response that produces water in a schedule-induced drinking procedure. Three food-deprived rats were exposed to a tandem schedule Fixed Ratio (FR) 1 Fixed Time (FT) t s of water reinforcement. In successive conditions the FT duration was either 0, 1, 2, 4, 8, 16, 0 or 2 s. During all conditions food was delivered according to a Random Interval 64 s. It was found that the number of responses for water decreased gradually as the water reinforcement delay was lengthened and that this effect was reversed when the rats were exposed again to immediate and 2 s delayed reinforcement. These results suggest that schedule-induced drinking is sensitive to the parameters of reinforcement documented in operant conditioning and questions the interpretation of schedule-induced drinking as a third class of behavior.

The effect of two different histories of reinforcement on response rate was examined. In a first phase three rats were exposed to a tandem RI 8 s FT 8 s reinforcement schedule while another three rats were exposed to a yoked RI 16 s reinforcement schedule. Another three rats were exposed to a tandem RI 8 s FT 8 s reinforcement schedule while another three rats were exposed to a yoked RI 8 s VT 8 s reinforcement schedule. In a second phase all rats were exposed to a RT 16 s reinforcement schedule. In a third phase the rats were exposed to the same reinforcement schedules as in the first phase. After a history of response dependent reinforcement response rate decreased for all rats under independent reinforcement. This effect was more pronounced for rats exposed to immediate reinforcement in the first phase than for rats under delayed reinforcement. Response rate re-establishment under dependent reinforcement was not affected by a history of independent reinforcement. In addition, an important finding was that although the programmed contingencies were different the obtained response-reinforcer intervals controlled response rate across all phases of the study.

The purpose of this study was to assess whether a brief psychological intervention would affect specific categories of performance in a professional team of first division soccer leagues in Mexico. 28 athletes, 11 titular and 17 substitute, participated in a 6 session program which included relaxation techniques, imagery, control of internal dialogue and problem solving.  A significative improvement for the titular group was recorded in defensive actions, change of game, and penalties (F=4.177, p=0.012; F=3.3635, p=0.029; F=19.6333, p<.0001, respectively), while the substitute group increased its offensive and change of game actions (F=5.6219, p=0.004; F=3.21, p=0.035, respectively). This study concludes that a brief intervention of this sort benefits differentially in three classes of actions both groups of soccer players, and that this positive effects are not explained by the mere participation in the league games of the professional season.

The variations on parameters of control and predictibility in avoidance schedules with humans, with the objective to obtain stress responses have had few researches. The goal of this study was to identify patterns of response under different contingencies of control and predictability and to evaluate the effect on levels of salivary cortisol. The subjects were 16 male universitary students between 18 and 28 years assigned randomly to three groups: Group A with controlable and predictable contingencies of noise presentation, Group B with controlable and impredictable and finally Group C with an uncontrolable and impredictable contingencies. The results showed differences on avoidance responses between groups. The subjects of Group A did not show effective responses on first session. In Group B, all the subjects learned to avoid the noise since first session. And in Group C, some subjects showed high rates of responses. The levels of cortisol fall down on groups with controlability conditions on experimental phases, in comparison with baseline, with low levels on the group with impredictable conditions, but in the group with unavoidable noise the levels rise up.

Some of the abilities and skills expected by the American Psychological Association (APA) in the performance of undergraduate psychology students, may be developed and practiced through strategic comprehension of specialized literature. Undergraduate Psychology students of different levels analyzed three different scientific behavioral readings using the Strategic Text Analysis Model. The procedure included four stages: (1) diagnostic evaluation, (2) modeling and feedback of the text analysis strategy, (3) didactic use of the model in classes, and (4) two more evaluations of text analysis. General findings show a generalized progress in the adequate use of model categories for all groups, which is considered as evidence of the ecological validity of the Model. Students reported a high level of satisfaction suggesting also high social validity of the model. Educative implications of the strategy for the instruction of professionals in Behavioral Sciences are discussed.

The present study was designed to propose a model that may explain human spontaneous recovery. In the present experiment we explored whether previously learned information would be integrated by the passage of time and hence produce reappearance of the forgotten material. Accordingly, we suggest that the Temporal Weighting Rule, derived from animal foraging studies (Devenport, 1998), may be applied to the study of human spontaneous recovery. Temporal Weighting Rule assumes that experiences are remembered depending on the relative temporal distance and subjective value. Manipulations of the temporal and subjective values in humans confirm one of the main predictions of the model. Spontaneous recovery is a function of the retention interval value only when the initial learning has grater subjective value. Results showed that spontaneous recovery is closely modeled by the Temporal Weighting Rule model and suggest also that it can predict the development of spontaneous recovery in human instrumental learning tasks.

An important aspect for the acquisition of instructional functions by a precontact description is the interaction of its relevance and specificity with the feedback frequency. Studies made in the area have focused its interest in the manipulation of the description’s Response (R) component; with the purpose of beginning with the assessment of the effects to manipulate Stimulus Situation (SE) component, and using a first order matching-to-sample task, 36 pre-graduate students were assigned to one of the nine experimental groups, that differ by the type of precontact description and the feedback frequency received. Results shows that participants that did not receive feedback, obtained the worse results, whereas those that received continuous feedback were superiors, being better those that received Specific and Non Pertinent precontact descriptions.

Behavior analysis originated from the tradition of the biological sciences, that favor the replication of data analyzing directly the behavior of individual subjects. Other areas of psychology that originated from the social sciences, favor the replication of data analyzing statistically grouped data, either of the behavior of the same subjects or of groups of subjects.  Although behavior analysts favor the analysis of individual data, there has been an increase in the number of articles published in specialized journals in which inferential statistics has been used to determine the reliability of a finding.  In this paper the basic premises of both strategies to infer the reliability of a finding, that derived from the biological sciences and that derived from the social sciences, are presented. The paper also includes the main criticisms and the arguments against those criticisms made by the defenders of each strategy. The conclusion is that each strategy has its own strengths and weaknesses and that in order to determine the reliability of a finding, a researcher should analyze the data following the strategy that allows him/her to advance scientific knowledge by comparing the current findings with those from previous research and thus answer unambiguously the research question.

The present paper argues for the systematization of the established knowledge on eating behavior in Conditioning and in Motivation on the basis of the quantitative contiguities between some of its controlling variables. A variable in common to both types of study is the temporal distribution of periods with and without access to food. Two doctoral theses illustrate this approach. In the first, the “natural” distribution of eating in rats with unrestricted access to food was determined over 24-hour periods and afterwards such distribution was deliberately distorted. Lengthening the periods without access and shortening the periods with access increased food consumption. In the second thesis the duration of the periods without access before and after each fixed access period were varied, also over 24-hour periods. Long periods without access before eating increased food consumption but varying the duration of the periods without food after eating had no systematic effects. It was concluded that this approach may bridge the gap between the established knowledge on eating in Conditioning and in Motivation.

This is an introduction to the special number on feeding research