Exocentric pointing in three-dimensional space

A study is reported of an exocentric pointing task in all three dimensions, in near space, with only two visible luminous objects--a pointer and a target. The task of the subject was to aim a pointer at a target. The results clearly show that visual space is not isotropic, since every set direction appeared to consist of two independent components--one in the projection onto a frontoparallel plane (tilt), the other in depth (slant). The tilt component shows a general trend across subjects, an oblique effect, and can be judged monocularly. The slant component is symmetrical in the mid-sagittal plane, requires the use of binocular information, and shows considerable differences between subjects. These differences seem to depend on the amount of binocular information used by each subject. There was a remarkably high level of consistency in the exocentric pointing, despite the absence of environmental cues. The within-subject consistency in the settings of the pointer corresponds to a consistency of about 1 min of arc in disparity of its tip, even though the pointer and target are separated by more than 5 deg.     

The Identity Status Approach: In Need of Fundamental Revision and Qualitative Change

This article is a response to the commentaries of Waterman (this issue) and Berzonsky and Adams (this issue) on my review of the identity status field (van Hoof, this issue). The commentaries illustrate that the identity status researchers attribute different meanings to the identity statuses and identity status research; while Waterman finds it difficult to recognize the field in my review, Berzonsky and Adams agree with several of my conclusions. The two commentaries represent two pillars on which the status approach rests. The difference between the review and the commentaries is that the first includes both pillars, whereas each commentary consists primarily of a selective presentation of assumptions and data. This response focuses on two main points of the commentaries: (a) are the statuses sufficiently validated? and (b) to what extent are they suitable for testing developmental identity hypotheses? Using specific examples I show that the line of reasoning in the commentaries and the data proposed in support of these arguments in fact often support the conclusions of my review, for I demonstrate that the statuses are insufficiently validated and that the statuses are unsuitable for measuring identity development. These conclusions call for a fundamental revision of the identity status approach and a qualitative change in identity theory and research. Finally, the alternative approaches presented by Berzonsky and Adams are evaluated with respect to their contribution to an indispensable qualitative change in the identity status field.     

Relative mislocalization of briefly presented stimuli in the retinal periphery

We studied the ability to localize flashed stimuli, using a relative judgment task. When observers are asked to localize the peripheral position of a probe with respect to the midposition of a spatially extended comparison stimulus, they tend to judge the probe as being more toward the periphery than is the midposition of the comparison stimulus. We report seven experiments in which this novel phenomenon was explored. They reveal that the mislocalization occurs only when the probe and the comparison stimulus are presented in succession, independent of whether the probe or the comparison stimulus comes first (Experiment 1). The size of the mislocalization is dependent on the stimulus onset asynchrony (Experiment 2) and on the eccentricity of presentation (Experiment 3). In addition, the illusion also occurs in an absolute judgment task, which links mislocalization with the general tendency to judge peripherally presented stimuli as being more foveal than they actually are (Experiment 4). The last three experiments reveal that relative mislocalization is affected by the amount of spatial extension of the comparison stimulus (Experiment 5) and by its structure (Experiments 6 and 7). This pattern of results allows us to evaluate possible explanations of the illusion and to relate it to comparable tendencies observed in eye movement behavior. It is concluded that the system in charge of the guidance of saccadic eye movements is also the system that provides the metric in perceived visual space.     

The many faces of the Still-Face Paradigm: A review and meta-analysis

The Still-Face Paradigm (SFP) designed by Tronick, Als, Adamson, Wise, and Brazelton (Tronick, E., Als, H., Adamson, L., Wise, S., & Brazelton, T. B. (1978). Infants response to entrapment between contradictory messages in face-to-face interaction. Journal of the American Academy of Child and Adolescent Psychiatry, 17, 1–13) has been used for many different purposes in over 80 empirical studies. In the current paper, the nature and correlates of infant behavior in the SFP were examined in a systematic narrative review and a series of meta-analyses. The results of the meta-analyses confirmed the classic still-face effect of reduced positive affect and gaze, and increased negative affect, as well as a partial carry-over effect into the reunion episode consisting of lower positive and higher negative affect compared to baseline. The still-face effect is very robust as it was found regardless of most sample variations such as infant gender and risk status, and regardless of most procedural variations, such as the length of the SFP episodes and the use of intervals between episodes. The few moderator effects that were found in the meta-analyses tended to put findings from the narrative review in a new perspective. Additional meta-analyses confirmed the narrative review in finding that higher maternal sensitivity predicted more infant positive affect during the still-face. Infants’ higher positive affect and lower negative affect during the still-face were predictive of secure attachment at age 1 year. The meta-analytic results for maternal depression were equivocal. Implications for future research include a need for studies testing the role of the adults’ identity (parent versus stranger, mother versus father) to elucidate the relationship-specificity of the still-face effect. Also, the role of maternal sensitivity and temperament as potential moderators of the still-face effect need to be examined further. On a procedural level, the effects of the timing of the still-face and of the duration of the reunion on infant responses deserve future research attention.     

Sex differences in the association of math achievement with visual-spatial and verbal working memory: Does the type of math test matter?

Previous research on sex differences in mathematical achievement shows mixed findings, which have been argued to depend on types of math tests used and the type of solution strategies (i.e., verbal versus visual-spatial) these tests evoke. The current study evaluated sex differences in (a) performance (development) on two types of math tests in primary schools and (b) the predictive value of verbal and visual-spatial working memory on math achievement. Children (N = 3175) from grades 2 through five participated. Visual-spatial and verbal working memory were assessed using online computerized tasks. Math performance was assessed five times during two school years using a speeded arithmetic test (math fluency) and a word problem test (math problem solving). Results from Multilevel Multigroup Latent Growth Modeling, showed that sex differences in level and growth of math performance were mixed and very small. Sex differences in the predictive value of verbal and visual-spatial working memory for math performance suggested that boys seemed to rely more on verbal strategies than girls. Explanations focus on cognitive and emotional factors and how these may interact to possibly amplify sex differences as children grow older.     

Preferred tempo in the learning of a gross cyclical action

Seventy-five subjects, randomly assigned to one of five training conditions, were required to learn to make large-amplitude, high-tempo, fluent movements on a so-called ski-simulator over a period of four days. Subjects trained under different tempo conditions. In four of the conditions the tempo was prescribed (“preferred”, high, low, or increasing), augmented feedback being provided to enable subjects to stay on “target”. “Preferred” tempo was based on the weight of the subject and was derived from a regression equation based on previous empirical research. In a fifth condition, subjects trained on “discovery learning” principles, i.e. without the tempo being prescribed. The results obtained on the three parameters (amplitude, frequency, and fluency) during the daily test sessions (in which the tempo was not prescribed) formed the data for the analyses.

A learning effect was apparent on all three parameters over the four-day training period. Subjects who trained under the high or the low prescribed tempos, however, were shown to produce significantly smaller amplitude movements than subjects who trained under the other three conditions. Training under the low-tempo condition was also shown to have disadvantageous effects on the parameters tempo and fluency. It was concluded that, for these kinds of action, training at a high or a low tempo—and particularly the latter—has undesirable effects. Such disadvantageous effects, however, were shown to be avoidable if training is begun with the “preferred” tempo of the subject and increased successively by 7% over days.     

Work, Competences and Learning Scenarios for the Future

Il arrive que les occasions d'apprentissage et d'acquisition des compétences et des aptitudes soient tiées aux opportunités professionnelles et ainsi, indirectement, au développement de l'économie. L auteur illustre, avec cinq scénarios, comment l'apprentissage peut être conditionné par des choix macro-économiques et macro-sociaux.
Opportunities for learning and the acquisition of competences or skills happen to be linked to work opportunities and thence indirectly to the development of the economy. The author sketches five scenarios indicating how learning may be conditioned by macroeconomic and macro-social choices.