Negative reinforcement and choice in humans

Participants chose between reinforcement schedules differing in delay and/or duration of noise offset. In Experiment 1 it was found that (1) immediate reinforcement was preferred to delayed reinforcement when amounts (durations) of reinforcement were equal; (2) a relatively large reinforcer was preferred to a smaller one when both reinforcers were obtained immediately; and (3) preference for an immediate, small reinforcer versus a delayed, large reinforcer increased as the delay preceding the large reinforcer increased, a sign of “impulsivity”. In Experiment 2, the schedules differed in amount or delay and equal intervals were added either to the constant parameter or the varied parameter. A shift from virtually exclusive preference to indifference occurred in the latter case but not the former, a result supporting a model of self-control that assumes that the value of a schedule depends on the ratio of amount and delay, and that choice between schedules depends on the ratio of these values.     

The opponent-process theory of motivation: VIII. Quantitative and qualitative manipulations of food both modulate adjunctive behavior

The present studies extend the opponent-process theory of acquired motivation to the schedule-induced polydipsia paradigm and more generally to adjunctive behavior. The theory suggests that manipulations of the quality and the size of the pellet presented on an intermittent schedule should be important modulators of polydipsia. In Experiment 1, presenting animals with preferred, less preferred, or least preferred food pellets on a fixed-time 120-sec schedule resulted in progressively lower levels of water intake. In Experiment 2, the quality and size of the pellet were manipulated factorially. These variables were found to interact in the control of both the development and maintenance of schedule-induced drinking. Thus, predictions from the opponent-process theory were supported by these findings.     

Spatial problem solving by rats: Exploration and cognitive maps

Two experiments were performed in an attempt to examine the contribution of the exploratory experience to performance on Maier's 3-table spatial problem-solving task. In the first experiment, the runway configurations were altered between exploration and testing. It was found that following an initial impairment animals exposed to the altered runway configurations could perform as well as animals not confronted with an altered runway configuration on the test trial. In the second experiment, animals were allowed to explore only elements of the problem space. Exploration of either the runways only or the tables only led to unsuccessful performance on the 3-table task. The results of both experiments were related to current theory of cognitive mapping.     

Perceptual speed and short term retention of visual stimuli in preschool children

Ninety children aged 26 to 69 months were tested individually on two tasks. The first required the identification of tachistoscopically presented visual stimuli. Presentation times were shortened after every fourth stimulus until a child no longer made three correct identifications out of a series of four. The second task required that similar identifications be delayed by intervals of 10, 20, and 40 seconds following presentation. The presentation time required for correct identification of the stimuli declined significantly across the age range examined while the maximum delay interval after which a correct response could be obtained increased. In addition, the two measures were statistically independent of each other although both were related to the age of the child. The results indicate that some of the perceptual processes which have been shown to be instrumental in the acquisition of reading skills exhibit a marked developmental change during the preschool years.     

Microcomputers in schools: Impact on the social life of elementary classrooms

Microcomputers are becoming increasingly available to schools, but little research is available concerning the impact of this technology for children. Two studies were conducted to examine some possible social effects of the use of microcomputers in elementary school classrooms where children are learning to program in LOGO. First, the task-related interaction that children engaged in with each other was observed and recorded in two classrooms (8- to 9-year-old s, and 10- to 11-year-olds) as the children worked on both computer and non-computer tasks. The children in both classrooms were significantly more likely to collaborate with each other when they worked with the computers, when compared with their interaction over other classroom tasks. The second study examined children's perceptions of their peers as resources for help with a variety of classroom tasks. When compared with other work, the computer context was the one where children more consistently identified certain of their peers as resources for help.     

Parent vs. teacher reactions to problematic behavior of head start children

Studies of disciplinary responses to preschool children's transgressions often assume that subjects share the same degree of concern for the misbehavior under study. Individual differences in the strengths of different transgressions in eliciting disciplinary interventions were studied in 31 black mothers and 31 black teachers of Head Start children. Simulated situational urgency to discipline was measured by a Q-sort of 60 items depicting 10 types of misconduct observed in preschool classrooms. Attitudes of concern for the significances of the behaviors for the children's development were obtained through a separate rank-ordering procedure. Parents saw significantly more urgency in transgressions of social deportment. Teachers viewed aggressive and antisocial behaviors as more urgent, and tended to show closer agreement between intervention urgency and attitudes. Whereas teachers' interventions may be interpreted as responses to group child-care demands, the parents' concern for social deportment invites several interpretations.     

Ambiguous-cue learning in preschool children: A test of the dimensional characteristics of task stimuli

Sixteen preschool children were administered a two-choice discrimination problem consisting of three stimulus compounds: the consistently rewarded stimulus, the consistently nonrewarded stimulus, and the ambiguous stimulus which was nonrewarded when paired with the positive, but rewarded when paired with the negative. When both pair of stimuli, positive-ambiguous and negative-ambiguous, were presented together the subject was required either to choose or to avoid the ambiguous stimulus depending upon the stimulus with which it was paired. In Experiment 1, when each of three stimuli (positive, negative, ambiguous) varied along one nonspatial cue dimension (color), performance was better on negative-ambiguous trials than positive-ambiguous trials. In Experiment 2, when the positive and negative stimuli varied along three nonspatial cue dimensions (colors and form) and the ambiguous stimulus varied along one of these dimensions (color), superior positive-ambiguous over negative-ambiguous performance was obtained. These findings complement those reported for other subjects and confirm Berch's (D. B. Berch, Learning and Motivation, 1974, 5, 135–148) predictions regarding use of differential numbers of cue dimensions.     

Mental addition in third,fourth, and sixth graders

Research on mental arithmetic has suggested that young children use a counting algorithm for simple mental addition, but that adults use memory retrieval from an organized representation of addition facts. To determine the age at which performance shifts from counting to retrieval, children in grades 3, 4, and 6 were tested in a true/false verification task. Reaction time patterns suggested that third grade is a transitional age with respect to memory structure for addition—half of these children seemed to be counting and half retrieving from memory. Results from fourth and sixth graders implicated retrieval quite strongly, as their results resembled adult RTs very closely. Fourth graders' processing, however, was easily disrupted when false problems were presented. The third graders' difficulties are not due to an inability to form mental representations of number; all three grades demonstrated a strong split effect, indicative of a simpler mental representation of numerical information than is necessary for addition. The results were discussed in the context of memory retrieval versus counting models of mental arithmetic, and the increase across age in automaticity of retrieval processes.