Le développement des opérations concrètes chez les Esquimaux canadiens1

Le développement des opérations concrètes est étudié dans l'optique piagé-tienne chez des enfants esquimaux canadiens âgés de 6 à 14 ans. Les résultats sont comparés à ceux d'une étude similaire chez des enfants aborigènes australiens et européens. Les stades et leur ordre hiérarchique se retrouvent de façon identique dans toutes les populations comparées, alors que le rythme de développement est affecté par des variables socio-culturelles. Chez les enfants esquimaux, les courbes de développement dans le domaine des conservations apparaissent asymptotiques, une plus ou moins large partie de l'échantillon n'atteignant pas le stade des opérations concrètes, alors que, dans le domaine des relations et des classes, et surtout dans le domaine spatial, il y a simple décalage de rythme par rapport aux enfants européens, ou développement chronologiquement semblable. Une partie des résultats est discutée en fonction de la distinction entre compétence et performance.     

A procedure for implanting chronic indwelling intraarterial catheters in nonhuman primates

A procedure for catheterizing the external iliac artery in nonhuman primates is described. This preparation can be used both for collecting blood samples and for infusing drugs. The preparation is well suited to long-term studies. Our experience indicates that, with appropriate maintenance, these catheters may remain patent for intervals of approximately 12 months.     

Career development theory

Super's theory of vocational development, initially formulated in the 1950s, has led to a number of important research programmes, focusing particularly on the concept of vocational maturity. The major findings of these studies are surveyed in this paper. They suggest that vocational maturity is a development characteristic which increases with age, is multidimensional in nature, develops at different rates in different individuals, and can help in the pre-diction of occupational satisfaction, occupational success, and career success.     

Flashbulb memories and the underlying mechanisms of their formation: Toward an emotional-integrative model

Flashbulb memories (FBMs) are detailed recollections of the context in which people first heard about important events. The present study investigates three models of the formation and maintenance of FBM. Two models have previously been proposed in the literature (Brown & Kulik, 1977; Conway et al., 1994). A third model of FBM that integrates theories of FBM and recent developments in the field of emotions is proposed. The present study compares these three competing models by investigating the FBMs that Belgian citizens developed upon learning of the unexpected death of their king Baudouin. Structural equation modeling revealed that, as compared to the two previously proposed models, the third model, which takes into account emotional processes, better explains FBM.     

The effects of plane rotation on the recognition of brief masked pictures of familiar objects

Two experiments examined the effects of plane rotation on the recognition of briefly displayed pictures of familiar objects, using a picture—word verification task. Mirroring the results of earlier picture naming studies (Jolicoeur, 1985; Jolicoeur & Milliken, 1989), plane rotation away from a canonical upright orientation reduced the efficiency of recognition, although in contrast to the results from picture naming studies, the rotation effects were not reduced with experience with the stimuli. However, the rotation effects were influenced by the visual similarity of the distractor objects to the picture of the object presented, with greater orientation sensitivity being observed when visually similar distractors were presented. We suggest that subjects use orientation-sensitive representations to recognize objects in both the present unspeeded verification and in the earlier speeded naming tests of picture identification.     

Inductive reasoning in psychometrics: A philosophical corrective

A brief historical overview of inductive logic is presented, and the logic of enumerative induction is discussed in its two generalized forms: rule-derivative and event-predictive. The psychometric tradition and experimental studies in induction are briefly recapitulated to indicate that they have not included event-predictive induction, that probabilities have not been prevalently included in rule-generative induction, and that the linguistic medium might be utilized more fully in the inductive area. An experimental test model designed in order to address these considerations is discussed. This test model of event-predictive induction in the linguistic medium was administered to a large sample of college graduates. Statistical characteristics of the tests and items were very satisfactory when compared to operational subtests. The theoretical significance of the study for future psychometric and experimental investigations in induction is discussed.     

An investigation of the influence of student behavior on teacher behavior

The relationship between student behavior change and teacher reactions to the change was investigated. One fifth-grade teacher served as the subject and two students in her class were employed as teacher change agents. In a multiple baseline design, the students' disruptive behavior (the independent variable) was modified without the teacher's knowledge. The teacher's reactions toward the students (the dependent variable) was monitored on several dimensions including: teacher behavior, teacher attitude toward students, and the quality of teacher verbal statements. Results indicated that student behavior change influenced the teacher's behavior. Implications are that students possess potent reinforcing properties for teachers and that students should be trained to be effective students.