An apparatus for the study of motivation and learning in children

An apparatus is described for use in learning ana motivation research with children. A dual track with cars permits singular or paired presentation of stimuli, presents different types of reinforcing events, counts the occurrence of these events, and automatically prints out latencies and correct or incorrect responses. Although designed primarily for studying the motivational properties of stimulus events, the apparatus is suitable for use in simple and complex learning studies.     

Generalization of relative competence mediating conformity across differing tasks

Subject correctness and group agreement were initially varied for college subjects performing a multiple-choice informational task (Canadian Knowledge Inventory). On a subsequent perceptual task (Raven's Standard Progressive Matrices), the dependent variable of conformity was assessed to examine generalization of relative competence formed on the informational task. It was seen that: (1) Those who perceived themselves to be less competent than the group on the first task exhibited the greatest level of conformity on the second task, thus replicating previous research on perceived relative competence as a determinant of conformity; (2) suspicion reduced conformity.     

Memory for objects in real scenes: The development of recognition and recall

Subjects examined crowded semirealistic layouts of toy objects, or photographs of these layouts, and then tried to identify added, moved or deleted items. The main study, involving 1st-, 3rd, 6th-graders, and adults, showed that although successful recognition of added items was superior to both recall of deleted items and recognition of moved ones, all three scores improved with age. In addition, false reports of “new” items decreased markedly in the older groups. The results argue against the widely held view that recognition memory undergoes little or no developmental improvement. No significant difference between real layouts and photographs appeared either in the main experiment or in replications involving shorter exposure (Experiment 2) or retarded subjects (Experiment 3).     

An information processing theory of aspects of the development of weight seriation in children

Children varying in age from six to 12 years were video-tape recorded while trying to seriate seven blocks according to weight with the aid of a scale. The typical behavior patterns that Piaget first described for the stages of intellectual development on this task were observed. Our protocols are analyzed in terms of stage specific base strategies coupled with a mechanism for translating them into task specific production systems. The actual simulation programs, written as production systems in a specially constructed language, BG, are evaluated in terms of how well they regenerate the protocols.     

TRAINING GENERALIZED RECEPTIVE PREPOSITIONS IN RETARDED CHILDREN1

Three retarded children were trained, using prompting and reinforcement procedures, to respond correctly to three categories of prepositional requests: “put the___ next to the___”, “put the___under the___”, and “put the___on top of the___”. Training sessions were alternated with probe sessions throughout the study. During training, a child was trained to respond to one request (e.g., “put the doll next to the cup”); during probing, the child was tested for generalization of this training to untrained requests. Responses to untrained requests were never prompted nor reinforced. The results showed that, as requests from one category were trained, the children's responses to the untrained requests of that category became increasingly correct. As discriminations among two or more categories were trained, the children's responses to the untrained requests of those categories also became increasingly correct. Thus, the methods employed appear to be successful in training generalized receptive discrimination among prepositional categories and possibly can be utilized in training other generalized receptive language skills.     

Influence of exploration time on haptic and visual matching of complex shape

The time adult Ss were allowed to explore stimuli was varied during intra- and cross-model equivalence matching involving vision and touch. Increasing time to explore either each standard, each comparison, or both standard and comparison from 4 to 16 sec significantly improved haptic intramodel matching. However, cross-modal matching, from either vision to touch or touch to vision, improved significantly only when time to explore each standard was increased. Videotape recordings of Ss’ hand movements revealed use of a greater variety of haptic scanning strategies by Ss in groups where increased exploration time enhanced accuracy. The difference in effects of exploration time on intra- compared to cross-model shape matching was discussed in terms of possible differences in requirements between the two tasks.     

Effects of a timing signal on simple reaction time with a rectangular distribution of foreperiods

It was hypothesized that the time course of preparation during a variable interstimulus interval (ISI) of a simple reaction time (RT) experiment was partly determined by the subjective distribution of conditional probabilities of the executive signal (ES). Sixty subjects performed a simple auditory RT task with various ranges of six ISI durations organized in rectangular frequency distributions. In order to give the subjects information about elapsed time during ISI, a recurring time-marking click, the periodicity of which was varied, was introduced during the ISI in one of the three series of trials each subject performed. A strong decreasing RT--ISI relationship was observed supporting the main hypothesis. However, a clear increase of mean RT over all ISIs combined, was also found. Because these two mixed effects were greatest when the click intervened at the possible times of ES occurrence only, three functions of time-information given by the click are discussed: (a) a reduction of the usual increase of time estimation error with increased ISI; (b) an increase of the subjects knowledge of the ISI range resulting from the discontinuity of the time-marking click which makes easier a discrete time-intervals numbering process; (c) a change of the simple-RT task into a discrimination task.     

Simultaneous linear prediction

Given a set of items (predictors) suppose one wishes to predict another set of items (predictands) in asimultaneous way. Such a situation may occur when the predictands are different measurable aspects of the same phenomenon. Alternatively one might wish to predict the success of an event (say a successfully performed task) which has many correlated or uncorrelated failure modes (say a set of possible mental or physical disabilities each of them by itself precluding the achievement of the said task.) In such a case a unidimensional prediction is of value only if prediction is simultaneous for all possible failure modes. A linear summarization of the predictors is suggested, which is unique and has maximum predictability value for all predictands simultaneously. Other summarizations or scores are found that give maximum explanation of residual measures on the predictands and that are uncorrelated. The set of those simultaneous linear predictions is compared to the set of the individual multiple regression predictions as used, for instance, in the same context by Horst [4] for each predictand given the original predictors. We suggest that this technique can be applied in particular to the summarization of a subset of items when the whole set of items constitutes the set of predictands.This work was initiated at Stanford University under contract 2-1-065 with U. S. Office of Education and was partly revised at the Université de Montréal.I wish to express my gratitude to Professor Herbert Solomon, Stanford University, for his unfailing assistance at all stages of my work.     

Flicker thresholds as determined by a modified conditioned suppression procedure,

Critical flicker fusion frequencies were determined as a function of stimulus intensity for three White Carneaux pigeons using a modified conditioned suppression paradigm as a threshold procedure. Critical frequencies ranged from 6 cps for the lowest intensity of 0.0014 ml to 77 cps for the maximum intensity of 41.86 ml.