Changes in step variability of new walkers with typical development and with Down syndrome

Models of human gait are based on adult locomotion. C. E. Bauby and A. D. Kuo (2000) proposed that adults rely on passive mechanisms at the spinal level to control motion in the anteroposterior direction and rely on direct monitoring of postural control in the lateral direction. The authors' purpose in this study was to determine if that model applies to control at the onset of walking in typically developing toddlers (n = 9) and in toddlers with Down syndrome (n = 6). Their longitudinal data suggested that toddlers control gait in a distinctly different manner than adults do. An adult pattern of control emerges with experience. In addition, the effect of experience on the emergence of that pattern is magnified by task-specific early intervention. The present data support the emergence and discovery of efficient patterns of control in this fundamental human behavior.     

The structure of language abilities at 4 years: a twin study

Normal language development was studied in 310 pairs of 4-year-old twins born in the United Kingdom in 1994. Twins were assessed individually in their homes on a diverse battery of language and nonverbal measures. Rotated factor analyses indicated the presence of a general Language factor (L) as well as a general Nonverbal (NV) factor. Moderate genetic influence was found for both L and NV abilities. Bivariate genetic analysis estimated a genetic correlation of .63 between L and NV abilities, implying that over half of the genetic influence on L overlaps with genetic influence on NV. These results suggest that at age 4, genetic influences on individual differences in language overlap substantially with genetic influences on individual differences in other cognitive abilities, although perhaps less so than later in development.     

Perception of objects that are translating and rotating

The motion of objects that are both translating and rotating can be decomposed into an infinite number of translational and rotational combinations. How, then, do such stimuli routinely elicit specific percepts and behavioral responses that are usually appropriate? A possible answer is that motion percepts are fully determined by the probability distributions of all the possible correspondences and differences in the stimulus sequence. To test the merits of this conceptual framework, we investigated the perceived motion elicited by a line that is both translating and rotating behind an aperture. When stimuli are presented such that a particular sequence of appearance and disappearance occurs at the aperture boundary, subjects report that the line is rotating only; furthermore, the perceived centers of rotation appear to describe a cycloidal trajectory, even when one aperture shape is replaced by another. These and other perceptual effects elicited by translating and rotating stimuli are all accurately predicted by the probability distribution of the possible sources of the physical movements, supporting the conclusion that motion perception is indeed generated by a wholly probabilistic strategy.     

Couples in crisis: Using self report instruments in marriage counseling

Self report inventories are often overlooked as a means of assessment in counseling with couples. A rationale for using self report instruments in working with couples is provided. Case studies are given to illustrate how one such instrument, ENRICH, can be used in developing a treatment strategy, making decisions about referrals, checking treatment progress, and following up on newlyweds.     

Schopenhauer on the ethics of suicide

The concept of death is of special importance in Schopenhauer's metaphysics of appearance and Will. Death for Schopenhauer is the aim and purpose of life, that toward which life is directed, and the denial of the individual will to life. Despite his profound pessimism, Schopenhauer vehemently rejects suicide as an unworthy affirmation of the will to life by those who seek to escape rather than seek nondiscursive knowledge of Will in suffering. The only manner of self-destruction Schopenhauer finds philosophically acceptable is the ascetic saint's death by starvation. Here the individual will to life is so completely mastered as to refuse even the most basic desire for nourishment, and thereby passes into nonexistence in complete renunciation of the individual will. Schopenhauer's attitude toward suicide nevertheless embodies an inconsistency. If, as Schopenhauer believes, the aim of life is death, and death is an unreal aspect of the world as appearance, then there appears to be no justification why the philosopher should not rush headlong into it - not to affirm the will to life in an abject effort to avoid suffering, but in order to fulfill life's purpose by ending it for distinctly philosophical reasons immediately upon arriving at an understanding of the appearance-reality distinction.     

Pathways to violence in the children of mothers who were depressed postpartum

The impact of postnatal depression on a child's risk for violent behavior was evaluated in an urban British community sample (N=122 families). Mothers were interviewed during pregnancy, at 3 months postpartum, and when the child was 1, 4, and 11 years of age. Mothers, teachers, and children reported on violent symptoms at age 11. Structural equation modeling revealed that the child's violence was predicted by the mother's postnatal depression even when her depression during pregnancy, her later history of depression, and family characteristics were taken into account. Violence was associated with symptoms of attention-deficit/hyperactivity disorder and problems with anger management. Children were most violent if mothers had been depressed at 3 months and at least once thereafter.