Shape-from-shading depends on visual, gravitational, and body-orientation cues

The perception of shading-defined form results from an interaction between shading cues and the frames of reference within which those cues are interpreted. In the absence of a clear source of illumination, the definition of 'up' becomes critical to deducing the perceived shape from a particular pattern of shading. In our experiments, twelve subjects adjusted the orientation of a planar disc painted with a linear luminance gradient from one side to the other, until the disc appeared maximally convex-that is, until the luminance gradient induced the maximum perception of a three-dimensional shape. The vision, gravity, and body-orientation cues were altered relative to each other. Visual cues were manipulated by the York Tilted Room facility, and body cues were altered by simply lying on one side. The orientation of the disc that appeared maximally convex varied in a systematic fashion with these manipulations. We present a model in which the direction of perceptual 'up' is determined from the sum of three weighted vectors corresponding to the vision, gravity, and body-orientation cues. The model predicts the perceived direction of 'up', contributes to our understanding of how shape-from-shading is deduced, and also predicts the confidence with which the 'up' direction is perceived.     

Weathering the storm: children's long-term recall of Hurricane Andrew

Children who experienced a highly stressful natural disaster, Hurricane Andrew, were interviewed within a few months of the event, when they were 3-4 years old, and again 6 years later, when they were 9-10 years old. Children were grouped into low, moderate, or high stress groups depending on the severity of the experienced storm. All children were able to recall this event in vivid detail 6 years later. In fact, children reported over twice as many propositions at the second interview as at the first. At the initial interview, children in the high stress group reported less information than children in the moderate stress group, but 6 years later, children in all three stress groups reported similar amounts of information. However children in the high stress group needed more questions and prompts than children in the other stress groups. Yet children in the high stress group also reported more consistent information between the two interviews, especially about the storm, than children in the other stress groups. Implications for children's developing memory of stressful events are discussed.     

Parent-adolescent relations and adolescent functioning: self-esteem, substance abuse, and delinquency

The present study examined parental support and monitoring as they relate to adolescent outcomes. It was hypothesized that support and monitoring would be associated with higher self-esteem and less risky behavior during adolescence. The diverse sample included 16,749 adolescents assessed as part of the National Educational Longitudinal Study. Both high parental support and parental monitoring were related to greater self-esteem and lower risk behaviors. The findings partially confirm, as well as extend, propositions in attachment theory.     

Longitudinal effects of lean production on employee outcomes and the mediating role of work characteristics

The author discusses results from a 3 year quasi-experimental field study (N = 368), which suggest negative effects on employee outcomes after the implementation of 3 lean production practices: lean teams, assembly lines, and workflow formalization. Employees in all lean production groups were negatively affected, but those in assembly lines fared the worst, with reduced organizational commitment and role breadth self-efficacy and increased job depression. A nonequivalent control group had no negative changes in outcomes. Mediational analyses showed that the negative effects of lean production were at least partly attributable to declines in perceived work characteristics (job autonomy, skill utilization, and participation in decision making). The study also shows the longitudinal effects of these work characteristics on psychological outcomes. Implications for lean production, work design, and employee well-being are discussed.     

The origins of height fear: an evaluation of neoconditioning explanations

The present research sought to establish a reliable and valid instrument for assessing the relevance of neoconditioning factors (e.g. latent inhibition, UCS inflation/revaluation, prior fear levels, prior expectancies of harm, fear and pain levels experienced during supposed learning events), in the development of human fear. Fifty-four undergraduate height-fearful students completed the new origins instrument (OQ-II), while 54 matched controls completed a modified version (OQM-II) that examined their prior experiences with heights. In general, few differences between groups were found. Height-fearful and control subjects did not differ on trait anxiety, the frequency of negative encounters with heights, the age at which these events had occurred, prior fear levels, prior expectancies of harm, or reports of UCS inflation/revaluation procedures. However, in a finding directly opposite to that expected from a conditioning account, the mean fear and pain scores reported by subjects who had experienced direct conditioning events were significantly higher in the non-fearful group than in the height-fearful group. These findings are discussed in terms of associative and non-associative models of fear.     

Psychosocial outcomes of urban African American adolescents born to teenage mothers

This is a study of psychosocial outcomes of adolescents born to teenage mothers. Adolescents' problem behaviors, psychological well-being, social support, school variables, and sexual behaviors are compared across three groups—those born to mothers 17 or younger, mothers 18–19 years old, and mothers 20 or older. Analyses from two samples of African American adolescents from Maryland (n = 205) and Michigan (n = 570) are reported. The results from both samples indicate that mother's age at birth is unrelated to adolescents' psychosocial outcomes. These two studies add to the limited number of analyses that examine adolescent outcomes for children of teen mothers. The results suggest that efforts to understand social structural determinants of healthy and problematic adolescent development may be more informative than examining the effects of mother's age. They also suggest that teen pregnancy prevention programs may be more effective if they are part of a larger prevention strategy that incorporates social structural change efforts and not only a focus on individual level change.     

Social and environmental factors influence the suppression of pup-directed aggression and development of paternal behavior in captive meadow voles (Microtus pennsylvanicus)

During summer, female meadow voles (Microtus pennsylvanicus) maintain territories and males do not engage in paternal care. As day length shortens, territories dissolve and males nest with females and young. Because paternal behavior has never been studied in free-living meadow voles during colder months or in the laboratory under short photoperiods, the authors examined whether males housed in short day (SD) lengths exhibited more frequent or better quality paternal behavior than males housed in long day (LD) lengths. Sexually and parentally inexperienced (naive) SD males exhibited proportionally more and qualitatively better paternal care than naive LD males. SD males were more responsive than LD males to classic social cues associated with prepartum aggression inhibition and paternal onset. SD sires also displayed qualitatively better paternal behavior than LD sires. These data suggest that meadow vole paternal state is regulated by specific social and environmental cues that may contain reliable information about ecological conditions that favor paternal care.