Information entropy and the variability of space-time movement error

The authors investigated the effects of movement time and movement distance on the information entropy and variability of spatial and temporal error in a discrete aiming movement. In Experiment 1, the authors held movement distance (100 mm) constant and manipulated 11 movement times (300-800 ms) of 8 participants. In Experiment 2, the authors tested 6 movement distances at 2 given movement times (15-60 mm at 300 ms; 40-240 mm at 800 ms) in 8 participants. The variability and entropy for spatial error increased with average movement velocity, whereas the variability and entropy for temporal error decreased as a function of average movement velocity. The common variance between variable error and entropy averaged about 84% and 72% for spatial and temporal errors, respectively, suggesting that the probabilistic approach of entropy reveals features that are not present in the standard deviation index of variability. The findings provide further evidence that information entropy may be a useful single-index representation of variability in the movement speed-accuracy relation.     

Color makes a difference: two-dimensional object naming in literate and illiterate subjects

Previous work has shown that illiterate subjects are better at naming two-dimensional representations of real objects when presented as colored photos as compared to black and white drawings. This raises the question if color or textural details selectively improve object recognition and naming in illiterate compared to literate subjects. In this study, we investigated whether the surface texture and/or color of objects is used to access stored object knowledge in illiterate subjects. A group of illiterate subjects and a matched literate control group were compared on an immediate object naming task with four conditions: color and black and white (i.e., grey-scaled) photos, as well as color and black and white (i.e., grey-scaled) drawings of common everyday objects. The results show that illiterate subjects perform significantly better when the stimuli are colored and this effect is independent of the photographic detail. In addition, there were significant differences between the literacy groups in the black and white condition for both drawings and photos. These results suggest that color object information contributes to object recognition. This effect was particularly prominent in the illiterate group.     

Longitudinal expressions of infant's prehension as a function of object properties

This longitudinal study examined the prehensile development of infants (9-37 weeks) under different task constraints (object shape, size and texture). At 9 weeks of age, the infants did not reach or make contact with the objects, but all 10 infants showed goal directed prehensile movement by about 17 weeks. As they continued to age the infants further differentiated an adaptive prehensile grip configuration to the object constraints. The pattern of longitudinal findings provides further evidence that: (1) the constraints of object properties play an important role in channeling the expressions of infant's prehensile functioning and (2) the classic observation by Halverson [Halverson, H. M. (1931). An experimental study of prehension in infants by means of systematic cinema records. Genetic Psychology Monographs, 10, 107-283] of an apparent order to the development of the fundamental prehensile sequence is task dependent.     

Caring for the stories that come to us: work narratives and their sacred promise

People often lack opportunity and place to reflect upon and share the sacred moments that occur in their work. Thus, these experiences are marginalized and neglected. Yet, they embody the soul of one's vocation. Drawing upon material from narrative family therapy, this article suggests that attending to and remembering these core but marginalized experiences is an activity for pastoral care. Narratives integrate spirituality and work. The article discusses the structure of narrative, its life cycle, and living in a universe composed of many stories. It explains a storytelling ritual that creates a safe place among the listeners who can then receive the narrative's sacredness. Two extended examples of sacred work narratives are given. A task for pastoral care is to construct hospitable places, sanctuaries, to hear the voice of these marginalized stories.     

Cone contributions to colour constancy

Colour constancy refers to the stable perception of object colour under changing illumination conditions. This problem has been reformulated as relational colour constancy, or the ability of the observer to discriminate between material changes and changes in illumination. It has been suggested that local cone excitation ratios play a prominent role in achieving such constancy. Here we show that perceptual colour constancy measured by achromatic adjustments is to a large part complete after 25 ms. This speaks against a prominent role for receptor adaptation, which takes significantly longer. We also found no difference in colour constancy between colour changes that were compatible with a change of illuminant, and between colour changes where local cone ratios were uncorrelated between the two illuminants. Our results show that constant cone ratios are not necessary for colour constancy.     

Perinatal infection, fetal inflammatory response, white matter damage, and cognitive limitations in children born preterm

Only sparse information is available about a possible association between antenatal infection outside the brain and subsequent cognitive limitations among preterm infants. Based on published studies, we provide a theoretical schema that links them via the fetal inflammatory response and neonatal white matter damage. We conclude that the relationship between antenatal infection and cognitive limitations deserves much further attention by researchers interested in the prevention of this undesirable outcome of prematurity.     

Moral identity and the expanding circle of moral regard toward out-groups

This article examines moral identity and reactions to out-groups during intergroup conflict Four studies suggest that a highly self-important moral identity is associated with an expansive circle of moral regard toward out-group members (Study 1) and more favorable attitudes toward relief efforts to aid out-group members (Study 2). Study 3 examines moral identity and national identity influences on the provision of financial assistance to out-groups. Study 4 investigates the relationship between moral identity and (a) the willingness to harm innocent out-group members not involved in the conflict and (b) moral judgments of revenge and forgiveness toward out-group members directly responsible for transgressions against the in-group. Results are discussed in terms of self-regulatory mechanisms that mitigate in-group favoritism and out-group hostility.     

Educational level, socioeconomic status and aphasia research: a comment on Connor et al. (2001)--effect of socioeconomic status on aphasia severity and recovery

Is there a relation between socioeconomic factors and aphasia severity and recovery? describe correlations between the educational level and socioeconomic status of aphasic subjects with aphasia severity and subsequent recovery. As stated in the introduction by, studies of the influence of educational level and literacy (or illiteracy) on aphasia severity have yielded conflicting results, while no significant link between socioeconomic status and aphasia severity and recovery has been established. In this brief note, we will comment on their findings and conclusions, beginning first with a brief review of literacy and aphasia research, and complexities encountered in these fields of investigation. This serves as a general background to our specific comments on, which will be focusing on methodological issues and the importance of taking normative values in consideration when subjects with different socio-cultural or socio-economic backgrounds are assessed.     

Task goals and change in dynamical degrees of freedom with motor learning

In this article, the authors examined the hypothesis that the direction of the change (increase or decrease) in the dynamical degrees of freedom (dimension) regulated as a function of motor learning is task-dependent. Adult participants learned 1 of 2 isometric force-production tasks (Experiment 1: constant force output; Experiment 2: sinusoidal force output) over 5 days of practice and a 6th day with augmented information withdrawal. The results showed that over practice, the task goal induced either an increase (Experiment 1) or a decrease (Experiment 2) in the dimension of force output as performance error was reduced. These findings support the proposition that the observed increase or decrease in dimension with learning is dependent on both the intrinsic dynamics of the system and the short-term change required to realize the task goal.