Perspective role-taking in young children

Children between the ages of 4 and 7 years were asked to select a photograph depicting the visual perspective of a puppet which was placed at various locations around a dollhouse in a modified version of Piaget and Inhelder's three-mountain task. A shielded condition was used for half of the children. Three types of errors were examined in relation to the shield condition, age, and type of vantage point (views from the corners and from the sides). Shielding of the stimulus array reduced egocentric errors among 4-year-olds, producing a pattern of responses more typical of that observed among older children. Increasing specificity in perspective role-taking with age was indicated by changes in error patterns. Finally, the task was more difficult on trials with corner views, particularly when the child's own view included some of the cues present in the puppet's perspective.     

The effects of social reinforcement and task difficulty level on the pleasure derived by normal and retarded children from cognitive challenge and mastery

In order to examine several factors influencing the pleasure derived from mastery, 32 normal first-grade children (mean MA = 7.7) and 32 MA-matched familial mentally retarded children were given puzzles representing four difficulty levels. Half of the children were socially reinforced for their successes and half performed in an experimenter-absent condition. There was more smiling among normal than retarded children, in the social reinforcement than in the experimenter-absent condition, and among girls than boys. The condition effect was greater for girls than boys. In the experimenter-absent condition, normal children displayed more pleasure on the difficult than on the easy puzzles, whereas the trend was just the reverse for the retarded children. Large within-sex differences were found for normal girls only, revealing that one subgroup derived more pleasure from the more difficult puzzles whereas another subgroup enjoyed the easier puzzles more. The findings were discussed in terms of the author's refinement of White's model of effectance motivation.     

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.     

Spatial perspective taking in young children.

Four- and five-year-old children were tested in a spatial perspective task employing a production format. They were shown a photograph of an aspect of a doll house and asked to generate the view on the photograph for a puppet that served as the observer. The house was mounted on a lazy Susan and could be rotated freely by the children. Puppet line of regard (to a corner, side, or rear of the house) and photograph type (fron, corner, side, or rear) constituted within-subject factors. Puppet position, photograph type, and age affected patterns of errors and proportion of correct responses. It was concluded that perspective taking is highly task dependent as well as dependent upon developmental status.     

The time course of learned helplessness, inactivity, and nociceptive deficits in rats

Four experiments are reported which explore the nature of the effects of inescapable shock on subsequent shuttlebox escape learning. The first experiment demonstrated that shuttle escape deficits dissipate within 48 hr after treatment with inescapable shock. Experiment 2 showed that exposure to inescapable shock suppressed unlearned activity in the shuttlebox and that this activity deficit recovered within 48 hr. Experiment 2A demonstrated that this shuttlebox crossing decrement was at least partly attributable to the inescapability of the shocks. These results suggested that activity factors might partly mediate the shuttle escape learning deficit reported in Experiment 1. Experiment 3 explored the possibility that activity and shuttle escape learning deficits are subserved by the effects of inescapable shock on pain sensitivity. The results supported this notion. It was found that rats were less sensitive to painful stimulation 24 hr after inescapable shock and that this analgesic tendency also dissipated within 48 hr after pretreatment. The implications of these results were discussed.     

Long-term memory in pigeons: I. The role of discrimination problem difficulty assessed by reacquisition measures II. The role of stimulus modality assessed by generalization slope

Pigeons learned either an easy or a difficult line angle discrimination (Experiment 1) or wavelength discrimination (Experiment 2), and then they were given a reacquisition test of retention after delays of 1 min, 1 day, or 1 week. Both percentage of responses to the S+ in the initial 10-trial block and number of blocks to criterion showed a progressive memory loss which was greater for the difficult problem. These results extend recent findings by using a free operant rather than a discrete trial task and by varying problem difficulty by altering the dimensional separation between training stimuli. In Experiment 3, pigeons were given variable interval training with either a wavelength or a line angle stimulus, and then they were tested for generalization in extinction after delays of 1 min, 1 day, and 1 week. With both dimensions, the relative gradients became progressively flatter with increasing delay intervals. This replicates earlier findings and extends them to the line angle dimension. The evidence of substantial forgetting in the first 24 h in all three experiments suggests that operant free-response procedures are more sensitive to forgetting effects than are discrete trial tasks.     

Development of phonetic memory in disabled and normal readers

The development of phonetic codes in memory of 141 pairs of normal and disabled readers from 7.8 to 16.8 years of age was tested with a task adapted from L. S. Mark, D. Shankweiler, I. Y. Liberman, and C. A. Fowler (Memory & Cognition, 1977, 5, 623–629) that measured false-positive errors in recognition memory for foil words which rhymed with words in the memory list versus foil words that did not rhyme. Our younger subjects replicated Mark et al., showing a larger difference between rhyming and nonrhyming false-positive errors for the normal readers. The older disabled readers' phonetic effect was comparable to that of the younger normal readers, suggesting a developmental lag in their use of phonetic coding in memory. Surprisingly, the normal readers' phonetic effect declined with age in the recognition task, but they maintained a significant advantage across age in the auditory WISC-R digit span recall test, and a test of phonological nonword decoding. The normals' decline with age in rhyming confusion may be due to an increase in the precision of their phonetic codes.     

A process model for water jug problems

We develop and evaluate a model for the water jug task in which a subject is required to find a sequence of moves (pouring operations) which produce a specified amount of water in each jug. Experiment 1 was designed to evaluate the meansends, move selection heuristics that are assumed by the model. Experiment 2 tested the model's predictions concerning those aspects of the water jug task that determine problem difficulty.A three stage process model incorporating GPS-like, means-ends heuristics and assumptions concerning the utilization of short- and long-term memory was able to account for differences across problems as well as details of the performance of subjects solving a given problem. We conclude that a GPS-like model that only selects one move at a time (no forward planning of move sequences or setting up of subgoals) can provide a good account of solution behavior in the water jug task.     

Reading rate and retention as a function of the number of propositions in the base structure of sentences

English texts were constructed from propositional bases. One set of 16-word sentences was obtained from semantic bases containing from 4 to 9 propositions. For another set of sentences and paragraphs, number of words and number of propositions covaried. Subjects read the texts at their own rate and recalled them immediately. For the 16-word sentences, subjects needed 1.5 sec additional reading time to process each proposition. For longer texts, this value increased. In another experimental condition reading time was controlled by the experimenter. The analysis of both the text and the recall protocols in terms of number of propositions lent support to the notion that propositions are a basic unit of memory for text. However, evidence was also obtained that while the total number of propositions upon which a text was based proved to be an effective psychological variable, all propositions were not equally difficult to remember: superordinate propositions were recalled better than propositions which were stucturally subordinate.     

Prior exposure to inescapable electric shock in rats affects extinction behavior after the successful acquisition of an escape response

In Expt 1, rats exposed to 64 inescapable electric shocks in a restrainer or merely restrained were later given either 0, 5, 15 or 30 escape/avoidance training trials with a two-way shuttlebox procedure that does not lead to interference with escape acquisition due to prior exposure to inescapable shock. After escape training all rats were given an escape/avoidance extinction procedure in which shock was inescapable. The rats which had received prior exposure to inescapable shock responded less often and with longer latencies in extinction than did the restrained rats. Experiment 2 demonstrated that this effect is caused by the inescapability of the initial shock treatment. These results were explained in terms of (a) associative interference which minimized the effect of shuttlebox escape training for the preshocked subjects, and (b) a stronger tendency to recognize the presence of an inescapable shock situation during extinction for the preshocked subjects. The relationship between these results and previous work demonstrating that exposure to the escape contingency mitigates the effects of inescapable shock exposure was also discussed.