The effects of exposure duration and practice on the immediate memory spans of children and adults

Immediate memory spans for alphabetic items were determined for second-grade, fifth-grade, and adult subjects. Subjects were tested on three days, ten trials per day at each of three exposure durations: 15, 50, and 200 msec. One half of the subjects were presented with exposure durations in an ascending order, the other half in a descending order. The results indicated that immediate memory span increases with age and practice. The exposure duration effect depended on the order and day in which durations were presented. There was a suggestion that the exposure duration effect was also dependent upon the age and sex of the subject. The ordering of array positions from most accurately reported to least accurately reported was identical for all three age levels, indicating that scanning strategies are well established at an early age.     

Environments as reinforcer systems in the study of job satisfaction

This paper examined differences in the degree to which fifteen specific sources of job satisfaction were related to and predictive of the overall satisfaction of department chairmen in the six model environments proposed by Holland (1973). The fifteen specific sources of job satisfaction were regressed on overall satisfaction, separately for chairmen in each environment, through the use of incremental stepwise multiple regression procedures. The results indicated that the overall satisfaction of chairmen in these six environments was differentially related to unique weightings and combinations of the fifteen predictor variables. It was concluded that environments, composed of essentially similar groups of people in different organizations, serve as job satisfaction reinforcer systems in a manner similar to organizations as illustrated by Dawis.     

Effects of a coactor's prediction on latencies to predict and indentify stimuli

On each of 300 trials E's confederate (C) verbalized which of two stimuli would occur; then S made a prediction. Following each presentation, S and C pulled a trigger to identify the stimulus. Two latencies were measured: the interval between C's and S's prediction (prediction time), and the interval between stimulus presentation and S's identification response (choice RT). Prediction times were significantly shorter when S's prediction agreed rather than disagreed with C's prediction, when S's preceding prediction was correct rather than incorrect, and when S was female rather than male. Choice RT was influenced by distributions of C's stimulus predictions and C's prediction outcomes in directions supporting an expectancy model.     

Reconstruction of arbitrary versus logical sequences by preschool children

The ability of preschool children to construct and reconstruct ordered sequences was examined in a series of four experiments. In Expt. 1, the task was to copy, with the model present or absent, the order of items pegged on a clothesline. In Expts. 2–4, the subjects were required to reconstruct ordered series of pictures from memory. In all experiments, the orders were either logical or arbitrary. Reconstruction of an arbitrary series of events is within the problem solving capacity of 4-yr-old children if (a) reconstruction takes place in the presence of the model or follows immediately upon the removal of the model and (b) the original sequence is presented simultaneously. If, however, the lag between viewing and reconstruction is increased and/or the original set is not viewed simultaneously, as a unit, performance declines. The provision of an inherent order to the items within a set, either by introducing a connective narrative, or a depicted logical sequence, is sufficient to maintain that order over time and to provide a unifying cohesion to the items when viewed successively.     

Resolving contradictory findings on sex and social class differences in children's responses to reinforcement

Contradictory results have been reported on the effectiveness of various reinforcers with children of different ages and socioeconomic classes. The present study considered the relative effectiveness of two types of verbal and one type of tangible reinforcement on a two-choice discrimination task (marble-in-the-hole) for preschool children. IQ and operant level were treated as covariates and accounted for the observed differences in performance between the 24 middle-class and 24 lower-class children and between the 24 males and 24 females. Disparate findings of previous studies regarding sex and social class differences might have been reconciled if baseline and IQ had been considered.     

Selective attention and the breadth of learning: A developmental study

Nursery school and second-grade subjects were trained on an optional intradimensional/extradimensional shift task with (1) no overtraining, (2) overtraining on the initial problem only, (3) overtraining on the shift problem only, or (4) overtraining on both the initial and the shift problems. Predictions concerning the effects of age and training conditions on the type of solution and the breadth of learning for the shift problem were derived from selective attention theory. However, the results were not consistent with the one-look assumption of such models. Instead, a multiple-look theory in which the breadth of attention varies with task demands seems most tenable.     

Effects of sucrose concentrations on single alternation runway responding in rats

Rats received runway training under alternating reward and nonreward in which rewarded (R) trials provided 32 or 4% sucrose concentration from a drinking tube and nonrewarded (N) trials provided a dry tube or, for half of the rats in the 32% condition, plain water. Both 32 and 4% concentrations yielded faster running on R trials than on N trials; but this effect was reliable only for the 32% condition. Compared to 4% sucrose, 32% sucrose yielded reliably slower running on N trials and unreliably faster running on R trials.