An action perspective on motor development

Motor development has all too often been considered as a set of milestones with little significance for the psychology of the child. Nothing could be more wrong. From an action perspective, motor development is at the heart of development and reflects all its different aspects, including perception, planning and motivation. Recent converging evidence demonstrates that, from birth onwards, children are agents who act on the world. Even in the newborn child, their movements are never just reflexes. On the contrary, they are purposeful goal-directed actions that foresee events in the world. Thus, motor development is not just a question of gaining control over muscles; equally important are questions such as why a particular movement is made, how the movements are planned, and how they anticipate what is going to happen next.     

Hypermnesia: A further examination of age differences between young and older adults

Previous studies that examined age differences in hypermnesia reported inconsistent results. The present experiment investigated whether the different study materials in these studies were responsible for the inconsistency. In particular, the present experiment examined whether the use of a video, as opposed to words and pictures, would eliminate previously reported age differences in hypermnesia. Fifteen college students and 15 older adults viewed a 3‐minute video clip followed by two free‐recall tests. The results indicated that older adults, as a whole, did not show hypermnesia. However, when older adults were divided into low and high memory groups based on test 1 performance, the high memory group showed hypermnesia whereas the low memory group did not show hypermnesia. The older adults in the low memory group were significantly older than the older adults in the high memory group – indicating that hypermnesia is inversely related to age in older adults. Reminiscence did not show an age‐related difference in either the low or high memory group whereas inter‐test forgetting did show an age difference in the low memory group. As expected, older adults showed greater inter‐test forgetting than young adults in the low memory group. Findings from the present experiment suggest that video produces a pattern of results that is similar to the patterns obtained when words and pictures are used as study material. Thus, it appears that the nature of study material is not the source of inconsistency across the previous studies.     

Infants’ ability to track and reach for temporarily occluded objects

Six‐month‐old infants were presented with a moving object that temporarily became invisible. The object moved on a horizontal path and was made invisible for either 400, 800 or 1,200 ms before being within reach. Two kinds of events were used to make the object invisible: blackout of the room lights and occlusion behind a screen. First, infants saw 6 trials of the fully visible motion, then 12 trials of a temporarily invisible motion and finally 6 trials of the fully visible motion again. Each infant was presented with only one of the 6 experimental conditions. The results show that reaching is much more severely affected by a period of temporary non‐visibility than tracking. The effects of the two modes of non‐visibility were rather different. In general, blackout deteriorated tracking and made the gaze lag at reappearance. It inhibited reaching but this effect attenuated with experience. Longer periods of blackout deteriorated tracking and reaching more. Compared to blackout, occlusion had both a facilitating and an inhibiting effect on infants’ actions. Tracking had less tendency to lag but reaching showed more severe inhibition. The results are discussed in terms of graded representations. Furthermore, it is argued that an occluder facilitates tracking by providing information of where the moving object becomes visible again and it inhibits reaching by interfering with the representation of the object behind the occluder.     

Unidimensionality of Abbreviated Proactive Personality Scales across Cultures

Vu la pertinence de la personnalité proactive et du comportement proactif pour l’efficacité des individus, des équipes et des organisations dans un environnement de plus en plus multiculturel, cette étude a examiné l’unidimensionnalité des formes abrégées de l’Echelle de Personnalité Proactive (PPS) de Bateman & Crant (1993) sur des données ni américaines, ni britanniques. L’unidimensionnalité des PPS à 10, 6, 5 et 4 items a été mise à l’épreuve grâce à une analyse factorielle et à une analyse de fidélité interne sur des échantillons indépendants provenant de trois pays: la Belgique (N= 822), la Finlande (N= 100) et l’Espagne (N= 100). Les résultats montrent que les versions de 4 et 5 items ne présentent aucune fidélité interne en Belgique, en Finlande et en Espagne, tandis que les deux autres formes abrégées sont satisfaisantes. L’analyse factorielle confirme qu’un modèle à facteur unique est une solution quasi optimale pour la PPS à 10 items. La PPS à 6 items mesure la personnalité proactive avec une fidélité interne cohérente à partir d’un facteur unique. Le score total sur l’échelle a été calculé par l’addition des scores sur les 6 items. On a obtenu sur un autre échantillon belge (N= 499) une corrélation des plus satisfaisantes (r= .92) entre la PPS de 6 items et la version originelle de 17 items. Given the relevance of proactive personality and proactive behavior for effectiveness of individuals, teams, and organisations in an increasingly multicultural context, this study investigated the unidimensionality of abbreviated forms of the Proactive Personality Scale (PPS; Bateman & Crant, 1993 ) beyond American and British data. The unidimensionality of the 10‐item, the 6‐item, the 5‐item, and the 4‐item PPS was tested through internal reliability analysis and factor analysis across independent samples in three countries (Belgium, N= 822; Finland, N= 100; Spain, N= 100). The results showed that the 5‐item and the 4‐item versions were not internally reliable in Belgium, Finland, and Spain, while the two other abbreviated forms of the PPS were. Factor analysis showed that a one‐factor solution for the 10‐item PPS was a sub‐optimal solution. The 6‐item PPS, however, measured the proactive personality in an internally consistent manner and through a single factor. The total score on the scale was calculated by adding up scores on the six items. In a separate Belgian sample (N= 499), correlations of the 6‐item PPS with the original 17‐item PPS proved satisfactory with r= .92.     

Altered emotional and motivational processing in the transgenic rat model for Huntington's disease

Huntington disease (HD) is caused by an expansion of CAG repeat in the Huntingtin gene. Patients demonstrate a triad of motor, cognitive and psychiatric symptoms. A transgenic rat model (tgHD rats) carrying 51 CAG repeats demonstrate progressive striatal degeneration and polyglutamine aggregates in limbic structures. In this model, emotional function has only been investigated through anxiety studies. Our aim was to extend knowledge on emotional and motivational function in symptomatic tgHD rats. We subjected tgHD and wild-type rats to behavioral protocols testing motor, emotional, and motivational abilities. From 11 to 15 months of age, animals were tested in emotional perception of sucrose using taste reactivity, acquisition, extinction, and re-acquisition of discriminative Pavlovian fear conditioning as well as reactivity to changes in reinforcement values in a runway Pavlovian approach task. Motor tests detected the symptomatic status of tgHD animals from 11 months of age. In comparison to wild types, transgenic animals exhibited emotional blunting of hedonic perception for intermediate sucrose concentration. Moreover, we found emotional alterations with better learning and re-acquisition of discriminative fear conditioning due to a higher level of conditioned fear to aversive stimuli, and hyper-reactivity to a negative hedonic shift in reinforcement value interpreted in term of greater frustration. Neuropathological assessment in the same animals showed a selective shrinkage of the central nucleus of the amygdala. Our results showing emotional blunting and hypersensitivity to negative emotional situations in symptomatic tgHD animals extend the face validity of this model regarding neuropsychiatric symptoms as seen in manifest HD patients, and suggest that some of these symptoms may be related to amygdala dysfunction.     

On Identifying Plausibility and Deliberative Public Policy

The identification of plausible epistemic approaches in science as well as the social problem definitions with which scientists implicitly work is essential for the quality of a deliberative public policy. While responding to the Nanofutures project, I will reflect on the essential elements of such a policy.     

“You Shouldn’t Look at Us Strangely”: An Exploratory Study on Personal Perspectives on Quality of Life of Adolescents with Emotional and Behavioral Disorders in Residential Youth Care

Applied Research in Quality of Life - Adolescents with Emotional and Behavioral Disorders (EBD) have complex needs and experience challenges in various developmental areas and life domains. The...     

Development of the infant's ability to retrieve food through a slit

The main purpose of the present study is to explore infants' ability to comprehend task manipulation, and whether they can feed themselves with a spoon when food has to be retrieved through a slit in a lid placed over a plate. To access the food, the infant has to align the bowl of the spoon with the slit. The orientation of the slit is manipulated, and certain orientations require more elaborate modifications of the feeding action than others. The infants are observed at monthly intervals, from 12 to 17 months of age. The presence of the lid affects the behaviour of the infants at all ages. Some behaviours become more immature. The infants grasp the spoon with more primitive grasp configurations, they grasp the spoon less consistently at the top of the handle, and they orient the spoon less consistently, with its bowl facing upwards. These differences decrease with age. The infants also make attempts to adjust to the constraints of the task, mainly by inclining the spoon more vertically, and rotating the hand in such a way as to align the spoon with the orientation of the slit. These adjustments improve with age. Copyright © 2002 John Wiley & Sons, Ltd.     

Effects of subclinical depression and aging on generative reasoning about linear orders: same or different processing limitations?

The performance of older adults and depressed people on linear order reasoning is hypothesized to be best explained by different theoretical models. Whereas depressed younger adults are found to be impaired in generative inference making, older adults are well capable of making such inferences but exhibit problems with working memory (Experiments 1 and 2). Restriction of the available study time impairs reasoning by nondepressed control participants and. as such, proves to be a good model of older adults' but not depressed participants' limitations (Experiment 3). These results are replicated comparing depressed and older participants with a control group in the same study, providing increased power and linking the results to additional control measures of processing speed and working memory (Experiment 4).