Assessing restricted stimulus control in typically developing preschool children and bees (Melipona quadrifasciata)

This study established a simple simultaneous discrimination between a pair of two-element compound visual stimuli in children (Experiment 1) and bees (Melipona quadrifasciata, Experiment 2). The contingencies required discriminative control by the compound and the question was whether the accurate stimulus control reached at this level would hold for each individual element of the compound. After baseline reached stability, probe trials assessed stimulus control by each single element of both S+ and S-. Average data showed that children (Exp. 1) tended to show stimulus control by a single element of the S+ compound. In Experiment 2 three of four bees showed stimulus control by both elements of S+ and did not respond or responded only infrequently to the elements of the S-. The children's decline in discrimination accuracy in probe trials, along with its maintenance during the baseline, replicated previous findings showing the development of restricted stimulus control (RSC). The precise stimulus control shown by the bees indicated that all elements correlated with reinforcement acquired stimulus control over their behavior; this confirms the extensive literature on visual discriminative learning in bees, but due to the small number of subjects it is premature to say that bees do not develop RSC...

Cuando la contigüidad no es suficiente: bloqueo en relaciones de equivalencia / When Contiguity is not Enough: Blocking Equivalence Relations

El fenómeno de bloqueo describe una circunstancia en la cual se impide o se dificulta el la transferencia de funciones entre eventos que se han presentado en una relación de contigüidad espacio-temporal. Desde una perspectiva teórica y empírica, el efecto bloqueo no debería predecirse en la adquisición de clases de estímulos aun cuando algunos de los estímulos de la misma clase se presenten simultáneamente. El presente estudio examina si la historia adicional de entrenamiento A-EI bien sea previa o posterior al entrenamiento con un estímulo muestra compuesto AX, es la variable crítica en la presentación del efecto bloqueo. Los desempeños obtenidos en las pruebas de bloqueo por los participantes de un grupo expuesto al procedimiento de bloqueo, un grupo expuesto al procedimiento de bloqueo invertido, y un grupo control, sugieren que el entrenamiento adicional con un solo elemento del compuesto no impide la inclusión de todos los estímulos dentro de la clase. Los casos en los que se observó el efecto bloqueo se interpretan en términos de tipos de percepciones elementales y configurales.

The blocking effect describes a circumstance which impedes function transfer among events that are part of a relation of spatiotemporal contiguity. However, theoretical and empirical evidence in stimulus class acquisition predicts that the blocking effect should not be observed even if some of the stimul11n the class are presented simultaneously as compound stimuli. The present study examines if additional A-EI training, whether prior or following training with a compound sample AX, constitutes a critical variable in the occurrence of the blocking effect. Performances in blocking tests by a group exposed to the blocking procedure, a group exposed to the backward blocking procedure and a control group were compared. Findings suggest that additional training with one member of the compound does not impede responding to all stimuli as members of the class. Instances where the blocking effect was observed are interpreted in terms of configural and elemental types of responding.