Active regulation of altitude as a function of optical texture

Institute of Aviation, University of Illinois, Urbana, Illinois Two empirical studies are reported that examine active regulation of altitude as a function of the type of ground texture. Three ground textures were examined: lines perpendicular to the direction of motion, lines parallel to the direction of motion, and the combination (i.e., square or checkerboard texture). Although subjects only controlled altitude, disturbances were: introduced on three axes: vertical, lateral, and fore-aft. The re8ults show a clear advantage for texture parallel to the direction of motion. However, in considering these results in the context of previous research on altitude control, the argument is made that there is no compelling evidence that suggests either parallel (splay) or perpendicular (density) texture is privileged with regard to altitude control. Rather, the most effective display for altitude control will be the one t-hat best isolates the optical activity associated with changing altitude from the optical activity arising from other sources of disturbance (such as forward locomotion). Such a display will make it easier for the observer to distinguish and respond specifically to the disturbances of altitude.     

Active regulation of altitude as a function of optical texture.

Two empirical studies are reported that examine active regulation of altitude as a function of the type of ground texture. Three ground textures were examined: lines perpendicular to the direction of motion, lines parallel to the direction of motion, and the combination (i.e., square or checkerboard texture). Although subjects only controlled altitude, disturbances were introduced on three axes: vertical, lateral, and fore-aft. The results show a clear advantage for texture parallel to the direction of motion. However, in considering these results in the context of previous research on altitude control, the argument is made that there is no compelling evidence that suggests either parallel (splay) or perpendicular (density) texture is privileged with regard to altitude control. Rather, the most effective display for altitude control will be the one that best isolates the optical activity associated with changing altitude from the optical activity arising from other sources of disturbance (such as forward locomotion). Such a display will make it easier for the observer to distinguish and respond specifically to the disturbances of altitude.     

On a neglected variable in theories of pictorial perception: Truncation of the visual field

Theoretical analyses of pictorial perception have concentrated on the consequences of conflicting flatness and depth information in pictures, but have failed to consider the perceptual effects of the truncation of the visual field attendant on any pictorial display. The importance of this variable both for methods of testing pictorial information and for theory building was demonstrated. Under four different viewing conditions, adults were asked to scale the size and distance of five isoceles triangles at five different distances. The four conditions were unobstructed static monocular view, peephole view, view through a rectangular frame, and view of all the stimuli photographed in a slide. The slopes of the peephole, truncation, and slide conditions’ scaling functions were all significantly smaller than the slope of the untruncated Monocular condition, and the Y-intercepts were all greater. A decrease in over-constancy in the size functions indicated a similar effect for all three truncated conditions. Results are interpreted as supporting the hypothesis that truncation of the visual field, both in pictures and in peephole views of the real world, causes a frontal shift in the localization of the visible field, with a resultant compression of perceived size and distance.     

Symbol-string sensitivity and children's reading

In this study of primary school children, a novel 'symbol-string' task is used to assess sensitivity to the position of briefly presented non-alphabetic but letter-like symbols. The results demonstrate that sensitivity in the symbol-string task explains a unique proportion of the variability in children's contextual reading accuracy. Moreover, developmental dyslexic readers show reduced sensitivity in this task, compared to chronological age controls. The results suggest that limitations set by visuo-spatial processes and/or attentional iconic memory resources may constrain children's reading accuracy.     

Artifice and virtue in the<Emphasis Type="Italic">Xunzi</Emphasis>

Xunzi was chronologically the third of the three great Confucian thinkers of China’s classical period, after Confucius and Mencius. Having produced the most comprehensive philosophical system of that period, he occupies a place in the development of Chinese philosophy comparable to that of Aristotle in the Western philosophical tradition. This essay reveals how Xunzi’s understanding of virtue and moral development dovetailed with his positions on ritual propriety, the attunement of names, the relation betweenli (patterns) andlei (categories), and his view ofdao (the way) in general. I have argued for a “constructivist” understanding of each of these aspects of Xunzi’s philosophy in some detail elsewhere (see Hagen 2000, 2001, 2002, 2003), and so here I will just briefly review a few key points before addressing their relation to moral development.     

Age-related differences in acquisition of perceptual-motor skills: working memory as a mediator

Aging is associated with reduced performance on information processing speed, memory, and executive functions tasks. Although older adults are also less apt in acquiring new perceptual-motor skills, it is unclear whether and how skill acquisition difficulties are associated with age-related general cognitive differences. We addressed this question by examining structural relations among measures of cognitive resources (working memory) and indices of perceptual-motor skill acquisition (pursuit rotor and mirror tracing) in 96 healthy adults aged 19-80 years of age. Three competing structural models were tested: a single (common) factor model, a dual correlated factors model, and a hierarchical dual-factor model. The third model provided the best fit to the data, indicating age differences in simple perceptual-motor skill are partially mediated by more complex abilities.     

A threat-detection advantage in those with autism spectrum disorders

Identifying threatening expressions is a significant social perceptual skill. Individuals with autism spectrum disorders (ASD) are impaired in social interaction, show deficits in face and emotion processing, show amygdala abnormalities and display a disadvantage in the perception of social threat. According to the anger superiority hypothesis, angry faces capture attention faster than happy faces in individuals with a history of typical development [Hansen, C. H., & Hansen, R. D. (1988). Finding the face in the crowd: An anger superiority effect. Journal of Personality and Social Psychology, 54(6), 917–924]. We tested threat detection abilities in ASD using a facial visual search paradigm. Participants were asked to detect an angry or happy face image in an array of distracter faces. A threat-detection advantage was apparent in both groups: participants showed faster and more accurate detection of threatening over friendly faces. Participants with ASD showed similar reaction time, but decreased overall accuracy compared to controls. This provides evidence for less robust, but intact or learned implicit processing of basic emotions in ASD.     

Integrating the criminal justice system into mental health service delivery: the worcester diversion experience

The substantial number of persons with mental illness encountered in many sectors of the criminal justice system has spurred actors from various agencies within that system to take actions aimed at reducing the growth of this population. These actions have included the development of specialty police units, jail diversion programs, and other mechanisms for channeling persons with mental illness out of the criminal justice system and into mental health treatment. The courts, too, have become involved in this effort with the recent development of the "mental health court," the latest of the "specialty" or "problem solving courts." These courts have not been without their critics, however, nor are they the only feasible approach to court-based diversion. This paper identifies and explores a range of options for structuring the relationship between criminal courts and local mental health systems. Beginning with a discussion of the rationale motivating the development of mental health courts, two alternatives to this specialty court model are discussed. One involves judges dealing with defendants having mental illness and substance abuse on a case-by-case basis. The other takes advantages of linkages that may already exist between most courts and the mental health providers who conduct their forensic assessments, expanding the role of these providers to serve as boundary spanners between courts and the components of local mental health systems. Regardless of the model adopted, however, appropriate linkages must exist between the courts and relevant providers. A case study is provided that demonstrates how the status of a locale's linkages can be evaluated and how the information derived from such evaluation can be used to improve the linkages between police, courts, and health and human services agencies.     

A Teacher-Consultation Approach to Social Skills Training for Pre-Kindergarten Children: Treatment Model and Short-Term Outcome Effects

This study evaluated the post-treatment outcome effects of a classroom-based social skills program for pre-kindergarten children, using a teacher-consultation model. The pre-K RECAP (Reaching Educators, Children, and Parents) program is a semi-structured, cognitive-behavioral skills training program that provides teachers with in-classroom consultation on program implementation and classroom-wide behavior management. Data on children's social skills and behavior problems were collected from parents and teachers at pre- and post-treatment, for 149 children aged 4–5 years (of whom 56% were girls). Significant treatment effects were found for teacher but not parent reports, with treatment group children improving significantly more than comparison group children in their teacher-rated social skills and internalizing and externalizing problems. These results provide some preliminary support for the efficacy of the program on children's social skills and behavior problems, and for a teacher-consultation model for training teachers to implement school-based mental health programs.