Sex Differences in Reversal and Nonreversal Shift Acquisition

The mediational hypothesis of reversal and nonreversal shift acquisition suggests that mediational behavior is equivalent to covert verbalization and thus related to verbal ability. This coupled with the general observation that males and females manifest significant performance differences in measures of verbal fluency leads to the prediction of an interaction between sex and type of shift. 48 male and female undergraduates were tested using a simultaneous discrimination procedure with the shift manipulation occurring during the first task. A 2 × 2 factorial analysis of variance yielded significant F ratios for sex, type of shift, and the interaction of sex × shift. Analysis of simple main effects showed significant comparisons between males and females on the nonreversal shift and between the reversal and nonreversal shift performance of females. These data were interpreted as supporting a mediational hypothesis of concept-shift behavior.

Relationship of False Recognition and Paired-Associate Learning Ability with Learning of Reversal and Nonreversal Shift

43 Ss were administered a false-recognition task, and a paired-associate learning task. Half the Ss were given a reversal shift task and the rest a nonreversal task. The paired-associate task was found to be unrelated to both the reversal and nonreversal tasks, whereas the false-recognition task was significantly related to the reversal shift but not to the nonreversal task. False recognition was also significantly related to the initial discrimination learned in the reversal shift, nonreversal shift paradigm. These results are interpreted in terms of a two-stage recognition model.

Cognitive Styles in Children and Performance on Piagetian Conservation Tasks

An investigation of the relationship of field-independence-dependence and verbal mediation-nonmediation to Piagetian conservation behavior in 88 kindergarten, first, and second grade boys. It was hypothesized that the field-independent and the verbally mediating boys will have grasped the principle of conservation to a significantly greater degree than field-dependent and nonmediating boys. The Children's Embedded-figures Test and a reversal-nonreversal shift task were administered in order to categorize the boys on the two main effect dimensions of field independence-dependence and verbal mediation-nonmediation. The Concept Assessment Kit-Conservation was administered to measure the ability of each boy to conserve. The procedure resulted in a three-way irregular analysis of variance design. The main effect of field independence was significant as hypothesized ( p < .05). Grade was also significant ( p < .01), but neither the verbal mediation main effect nor any of the interactions was.

Overtraining Effects on Reversal and Nonreversal Discrimination Shifts with a Continuously Reinforced Free Operant

Rats were trained on a single-stimulus, successive discrimination in a free operant situation with continuous reinforcement of responding to S+. Ss were given 0, 4, or 8 days of overtraining (OT) after reaching the discrimination criterion. Half of the Ss were given a reversal shift (RS) and half a nonreversal shift (NRS). An irrelevant stimulus dimension was present at all times in Exp. 1, and it was absent in Exp. 2. OT did not affect RS or NRS learning in either experiment. NRS learning was faster than RS learning. These results were contrasted with other studies which have reported that OT facilitated RS learning and impeded NRS learning. Certain theoretical interpretations of discrimination learning, particularly Sutherland's treatment of centrally mediated attentional mechanisms, were critically discussed in light of the present findings.