Determinants of stability in the perception of subjective contour

The present study constituted an initial experimental effort to examine the fragmentation characteristics of subjective contours within the photopic and upper 5cotopic ranges of illumination. Four stimulus factors known to influence the visibility of subjective contours—target luminance, inducing area size and contrast, and contour orientation—were examined. Results indicated that subjective contours are indeed unstable perceptual phenomena. On the average, fragmentation or fading occurred after only 15 sec of observation, and some farm of stimulus outage was present for 28% of the viewing time of each stimulus. Fragmentation latency was significantly shorter and total time in fragmentation longer for diamond than for square contours, and total time in fragmentation varied inversely with inducing-area size. Fragmentation tendedto occur in whole units rather than in isolated elements, a result reminiscent of the fading of real Contours under impoverished viewing conditions.     

Stereoscopic perception with brief exposures

In this report we describe the results of an experiment in which we demonstrated that a powerful and compelling stereoscopic experience is elicited with very brief (< 1 msec) stimulus durations. The observers were highly successful in recognizing briefly flashed, stereoscopic, random-dot surfaces in the absence of monocular contours. The results are shown to be closely related to the range of depths for any stimulus form; however, the recognition thresholds were nonmonotonic as a function of disparity. Previous investigators have disagreed about the existence of a temporal threshold for stereopsis. We believe that prior findings suggesting that stereopsis cannot occur at short exposure durations are probably due to inadequate control of fixation disparity. Therefore, there is poor dichoptic image registration when a stereoscopic stimulus is presented. The present results also raise difficulties for any theory of stereopsis that requires eye movements.     

A Description of the Continuum of Eating Disorders: Implications for Intervention and Research

Many authors have proposed the notion of an eating disorder continuum to aid in the understanding of similarities and differences among various types of eating disturbances and disorders. The purpose of this article is to present an eating disorders continuum and to describe groups on the continuum by highlighting differences among the groups on behavioral, cognitive-attitudinal, and self-esteem issues. The relationship of the continuum to the developmental course of eating disorders is discussed. Prevention, early intervention, and treatment programs for various groups on the continuum are presented. Recommendations for future research on the continuum of eating disorders are provided.     

Attributions about spouse abuse: It matters who the batterers and victims are

The present study examined college students' (86% white) reactions to scenarios of three types of domestic violence situations. Subjects read a brief newspaper report of a battering incident and afterwards rated the situation and participants on a variety of scales. The scenario described either a (1) husband battering his wife, (2) wife battering her husband, or (3) gay male battering his lover. In addition, there was or was not an apparent verbal provocation by the victim. Results showed the harshest evaluation of a batterer who was not provoked. A greater responsibility was placed on the victim in the battered husband scenario, which generally was taken less seriously than the battered wife case. Results suggest the need to examine a diversity of battering situations and variables in order to fully understand attributions made about such situations.     

Improving the quality of careers guidance: Towards an understanding of the development of personal models

The process by which careers officers develop personal models of guidance through the interaction of theoretical knowledge with their experiences of training and practice is examined. Semi-structured interviews were conducted with 11 careers officers. Questions were asked about the training and development of careers officers in the practice of careers guidance and counselling with young people. The responses are considered in relation to theories of careers choice, careers counselling and guidance, models of counselling, and the supervisory role in the development of individual practice. Some recommendations are made for improvements to training and supervision for careers guidance.     

Parental Attributions of the Causes of Their Children's Behavior

We investigated causal attributions parents made regarding their children's best and worst behavior while the children were taking methylphenidate (MPH) for Attention-Deficit Hyperactivity Disorder (ADHD). Twenty-six parents were surveyed each week for six weeks using the Parent Attribution Scale-Revised. This scale measures parents' attributions of the causes for their children's behavior when taking MPH to treat symptoms of ADHD. When attributing causes for best behavior, the parents rated their children's effort most often followed by their own effort and the positive medication effects. When attributing causes for worst behavior, the parents rated their children's lack of effort most often followed by inadequate medication effects and their own lack of effort. Our study suggests that parents rate effort most often when making attributions for their children's best and worst behavior. When making attributions for best behavior only, parents saw no difference between their own efforts and the effects of medication. When making attributions for worst behavior only, parents were more likely to blame their children's lack of effort and the ineffectiveness of medication more often than their own lack of effort.     

Models and theories II: Issues and applications

This paper is the second of a two‐part series on models and theories, the first of which appeared in International Studies in the Philosophy of Science, Vol. 11, No. 2, 1997. It further explores some of themes of the first paper and examines applications, including: the relations between “similarity” and “isomorphism”, and between “model” and “interpretation”, and the notion of structural explanation.     

Safe and Unsafe Sexual Intentions and Behavior: The Effects of Norms and Attitudes1

A study of 85 heterosexual men, 85 heterosexual women, and 82 homosexual men was undertaken to examine the variables that influence intentions to engage in different sexual practices and actual sexual behavior. On the basis of Fishbein and Ajzen's (1975) theory of reasoned action, it was predicted that the strength of intentions would be related to whether behavior was in accord with intentions. Consistent with expectations, the strength of intention to engage in six different sexual practices (e. g., vaginal intercourse, anal intercourse, oral sex) and the three strategies that modify the risk of HIV transmission (sex with an exclusive partner, sex wearing a condom, and looking for a new partner) predicted actual behavior. Second, it was proposed that attitudes toward one's sexual practices and norms would be related to intentions to engage in safe sex. To reflect differential levels in the safety of behavioral intentions, five safety intention groups were formed: (a) nonpenetrative sex, (b) penetrative sex in an exclusive relationship with a condom, (c) penetrative sex in an exclusive relationship without a condom, (d) penetrative sex in a nonexclusive relationship with a condom, and (e) penetrative sex in a nonexclusive relationship without a condom. Norms, rather than attitudes, distinguished the five safety intention groups. the groups intending to engage in safe sex (nonpenetrative sex or penetrative sex with a condom) perceived lower levels of social approval for their sexual practices than the noncondom groups. Additional analyses showed that past behavior had a stabilizing effect on the intention-behavior relationship, but only for the nonpenetrative and noncondom safety intention groups.