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61.
The ability to make egocentric distance estimates of a single point source of light, seen in darkness and without the cues of changing size and luminance, was investigated in sixteen observers. The attenuation required to maintain constant luminance, when the target was viewed from different distances, was shown to follow the inverse square law providing the angle subtended by the light was less than 20 s arc. Distance changes were also simulated by means of a split mirror which produced vergence cues, or by test lenses to provide accommodation cues. Over the range 0.5 to 9.2 m distance estimates were surprisingly accurate, although there was some overestimation of near and underestimation of far distances. Most observers made good judgements when only convergence cues were varied, whereas no observers made consistently good judgements when only accommodation cues were varied. The difficulties are discussed in terms of the accommodation-convergence link. When distance was simulated by changing convergence and accommodation cues, estimates were not as good as when real distance was changed. Since good estimates were made with brief target exposures, these judgements were not based on subsequent convergence or accommodation changes. It is suggested that the metric or reference against which the apparently absolute judgements were made was the efferent demand signal associated with a 'resting' position of convergence in darkness.  相似文献   
62.
63.
Telehealth research in the field of applied behavior analysis (ABA) has focused on the training and supervision of others to implement various behavior analytic procedures. Current guidelines for practicing telehealth suggest that direct telehealth services may be appropriate for some individuals diagnosed with autism spectrum disorder, but more research is needed. This study evaluated the effects of discrete trial teaching with instructive feedback in a dyad arrangement delivered directly via telehealth to teach tact relations to 6 children diagnosed with autism spectrum disorder. All participants and the experimenter were located in different physical locations. All participants learned their primary and secondary targets, and 5 of the participants acquired the observational primary and secondary targets without direct teaching. Areas of future research and clinical implications are discussed in the context of telehealth service delivery.  相似文献   
64.
This investigation evaluated the degree to which creativity training, idea generation instruction, and creative process impacted idea production, creativeness of solutions, and leadership effectiveness. Three sets of hypotheses were tested with a 114 groups of adults. First, groups whose members had some (i.e., one CPS course) or advanced training (i.e., graduate-level study in creativity or creativity professionals) were significantly more effective at idea generation than groups without training. Furthermore, leaders with some and advanced training were perceived to be significantly more effective than those with no creativity training. With respect to creativeness of solutions, the advanced training groups outperformed all others. The second set of hypotheses focused on the effectiveness of idea generation instruction (i.e., instructions without brainstorming, brainstorming, and brainstorming with criticism). Analysis revealed no significant difference for idea generation instruction relative to idea production or creativeness of solutions. The final set of hypotheses examined the use of a simple process structure for groups without prior creativity training (i.e., distinct phases for idea generation and solution development). Analysis revealed that those meetings that followed a simple process structure out performed groups that did not follow a process for both idea generation and creativeness of solutions. Further results are presented and implications discussed.  相似文献   
65.
Suicide is a reaction to internal and external sources of stress and the impact of life events. In the elderly these situations are prevalent in many who are not suicidal and instead choose life. They represent what may be called rational nonsuicide. They are far more frequent than rational suicide. Nevertheless, considerably more is written about rational suicide than its alternative. The reasons for this phenomenon are reviewed, and suggestions are made for a rational approach to the affirmation of life rather than its rejection, even to the very end.  相似文献   
66.
Drawing on terror management theory (TMT), we discuss the psychological motivations that shape personality at two levels: the characteristically human personality common to us all and the individual differences that distinguish some people from others. TMT posits that the motivation to protect the self against deep-rooted fears about mortality drives people to maintain meaningful, reliable conceptions of reality and positive evaluations of themselves, two broad tendencies that form the foundation of every person’s personality. We review studies showing that mortality reminders increase efforts to bolster cultural sources of meaning and self-esteem in similar ways across individuals and cultures. TMT also posits that individual differences in personality partly reflect the different sources of meaning and self-esteem that people invest in to assuage mortality fears. We review evidence that individual differences predict the degree and direction of people’s defensive responses to mortality reminders. Directions for future research are discussed.  相似文献   
67.
This study explored the association between interpersonal factors and depressive symptoms in first-time mothers over the first two years of parenthood. An interpersonal style characterized by dependency, recollections of rejection in childhood, and current relationship characteristics was assessed in a nonclinical sample of 133 women. The final model explained 52% of the variance in depressive symptoms at 24 months. Controlling for initial symptom levels, interpersonal variables explained 24% of the outcome variance. The findings suggest that two interpersonal attributes, peer rejection in childhood and a dependent interpersonal style, are particularly important to our understanding of depressive symptomatology.  相似文献   
68.
Even though it can be shown that verbal knowledge of results (KR) is redundant with sensory feedback for learning certain motor skills, such findings do not eliminate the possibility that when KR is available it influences underlying learning processes. In order to examine the function of KR more closely, two experiments were designed in which the subjects received conflicting information about their own sensory feedback and the KR presented by the experimenter. In Experiment 1, two erroneous-KR groups, a correct-KR group, and a no-KR group performed 150 practice trials on a simple anticipation timing task and then performed three no-KR retention tests of 30 trials each following intervals of 10 minutes, 1 week, and 1 month. The results supported previous findings that providing correct KR is redundant in anticipation tasks. However, learning was influenced by KR as subjects performed according to the erroneous KR information, thereby ignoring their sensory feedback even after a 1-month interval. In Experiment 2, subjects practised a more complex striking response for the anticipation task for 75 trials and then performed no-KR retention trials either immediately, or 1 day or 1 week later. One of the groups received erroneous KR after 50 practice trials with correct KR. The results confirmed and extended those from Experiment 1, as erroneous KR, even after initial practice with correct KR, influenced retention performance. These results indicate that although KR provides information that is not needed to learn anticipation timing skills, this augmented verbal information is a dominant source of information that influences underlying cognitive processes involved in learning motor skills.  相似文献   
69.
In five experiments, we examined 3‐ to 6‐year‐olds’ understanding that they could gain knowledge indirectly from someone who had seen something they had not. Consistent with previous research, children judged that an informant, who had seen inside a box, knew its contents. Similarly, when an informant marked a picture to indicate her suggestion as to the content of the box, 3‐ to 4‐year‐olds trusted this more frequently when the informant had seen inside the box than when she had not. Going beyond previous research, 3‐ to 4‐year‐olds were also sensitive to informants’ relevant experience when they had to look over a barrier to see the marked picture, or ask for the barrier to be raised. Yet when children had to elicit the informant's suggestion, rather than just consult a suggestion already present, even 4‐ to 5‐year‐olds were no more likely to do so when the informant had seen the box's content than when she had not, and no more likely to trust the well‐informed suggestion than the uninformed one. We conclude that young children who can ask questions may not yet fully understand the process by which they can gain accurate information from someone who has the experience they lack.  相似文献   
70.
This study examines the relationship of life stress, daily hassles, and perceived self-efficacy to adjustment in a community sample of 32 men and 32 women between ages 65 and 75. In a structured interview, negative life change events, daily hassles, self-efficacy, depression, psychosomatic symptoms, and negative well being were assessed. Both negative life events and daily hassles were related to psychological distress and physical symptoms for men, and hassles were associated with psychological distress and physical symptoms for women. An inverse relationship between self-efficacy and maladjustment was also found. Hassles showed the most powerful relationship to distress.  相似文献   
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