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991.
Dittmar, Warm, and Dember (1985) suggested that visual parallax may lead to declines in perceptual sensitivity over time in spatial vigilance tasks involving comparative judgments. The present study tested this possibility by restraining subjects' head movements during a 1-hr vigil in which comparative (simultaneous task) or absolute (successive task) judgments of line length were necessary for signal detection. Under free-viewing conditions, perceptual sensitivity declined over time with both types of tasks. Head restraint eliminated the sensitivity decrement in both cases. The results highlight signal quality as a crucial determinant of perceptual decrements in sustained attention.  相似文献   
992.
The FACES instrument, based on Olson's Circumplex Model of family functioning, was administered to 96 adolescent drug-abuse clients and their parents. The majority of these families categorized themselves as "disengaged" (rather than "enmeshed") on the cohesion dimension, and as "rigid" (rather than "chaotic") on the adaptability dimension. These findings were unexpected as they were substantially different from published findings on families with other types of problems. Family therapists, utilizing Olson's Clinical Rating Scale for the Circumplex Model, characterized significantly more of these same families as "enmeshed," rather than "disengaged." Possible explanations for the difference between the therapists' perceptions and the families' self-perceptions are discussed.  相似文献   
993.
In the context of an annual fundraising drive for the American Society, two field experiments were conducted to test the relative effectiveness of suggesting either small or large contributions. In experiment 1, as part of a door-to-door campaign 300 people were randomly assigned to: (a) a standard request for contributions (control); (b) the standard request plus the words, “even a penny will help”; or (c) the standard request plus the words, “a generous contribution would really help.” As hypothesized, asking for a generous contribution significantly decreased the percentage of people who donated and failed to increase the average size of contribution by those who gave. Inconsistent with previous findings, the even-a-penny condition did not increase donating. In the second experiment conceptually similar requests were made in a mail-out campaign: 6,000 requests were made—2,000 suggested relatively small amounts (options beginning at $5); 2,000 suggested large amounts (options beginning at $5); and 2,000 were unspecified with regard to recommended amount (control). As expected, compared to the control condition, asking for small amounts increased the proportion of donors to nondonors without decreasing the average size of contributions, while asking for large amounts decreased the proportion of donors to nondonors without increasing the size of contributions. It is suggested that the findings have important implications for charitable fundraising.  相似文献   
994.
Two groups of six mentally retarded adults were exposed to either a “say/do” correspondence training program or a “do only” reinforcement procedure to evaluate the suggestion of Rogers-Warren and Baer (1976) that reinforcement of the nonverbal target behavior in the absence of the relevant verbal behavior may account for the behavior changes seen in correspondence training. The participants worked in an experimental setting on a variety of manipulatory responses leading to various auditory and visual consequences. Analysis of individual patterns of responding indicated no apparent differences between the groups during training; four individuals in each group appeared to develop generalized correspondence skills. We conclude that the outcome of correspondence training may not necessarily be verbal regulation of behavior as is assumed. Rather, we suggest that the notion of rule-governed behavior can best account for the type of behavior changes seen in correspondence studies.  相似文献   
995.
The development of generalized job initiative was examined with three severely retarded men working in an industrial assembly area of a sheltered workshop. Interventions included discrimination training, role-play training, and self-monitoring. For each participant, training was applied sequentially to three sets of job initiative behaviors. Intensive training was required to establish the first set of job initiative behaviors; however, the second and third sets of job initiative behaviors were learned with only discrimination training. The discussion summarizes the findings and suggests research needed to develop more powerful learning-to-learn paradigms.  相似文献   
996.
The acquired immune deficiency syndrome (AIDS) has rapidly become the most serious medical consequence of injecting illicit drugs. Its potential impact on intravenous (IV) drug use is enormous. Human immunodeficiency virus (HIV, also known as HTLV-III and LAV), the virus that causes AIDS, appears, usually, to lead to lifelong infection. At present there is no effective treatment, and the treatments under development may require lifelong antiviral therapy. Since most of the antibody produced in response to HIV infection does not neutralize the virus, and since there is substantial genetic variation in the virus, it will be difficult to develop a vaccine. Even after vaccines are developed, testing their safety and efficacy will be formidable problems. Until either effective treatment or vaccines are developed, control of the epidemic among IV drug users must be attempted through behavior change/prevention efforts. In this paper we will review the epidemiology of AIDS among IV drug users and characteristics of the IV drug-use subculture relevant to prevention efforts. We will then identify different target groups for these prevention efforts, present available evidence about behavior change in these groups, and then briefly discuss how to prevent transmission of HIV to heterosexual partners who are not themselves IV drug users and to the children of IV drug users.  相似文献   
997.
The present study examined the hypothesis that individuals are more influenced by a drug name than by the side effects associated with that drug when making recommendations regarding regulation. Subjects recommended the amount of regulation that should exist for eight drugs ranging from aspirin to LSD. One third of the subjects were asked to make recommendations based only on the drug name. Another third made recommendations based only on the facts associated with the drugs (i.e., side effects, symptoms). A final third made recommendations based on both facts and the drug name. Results indicated that, when given only the facts, subjects' recommendations deviated greatly from the actual regulation of the drugs but that the facts were ignored if subjects knew the name of the drug. These results suggest that critical information may be ignored when decisions are made about drug regulation. The implications for self-regulated drug use are discussed.  相似文献   
998.
Fourth-, fifth-, and sixth-grade students responded to a questionnaire concerning their experiences with electronic videogames and computers. Teacher ratings of academic achievement, personality characteristics, and behavior patterns were also obtained for each student. These data were used to examine a number of hypotheses concerning potential harmful or beneficial effects of electronic videogames on school-age children, and to provide preliminary evidence concerning the correlates of computer usage by school-age children. Videogame usage showed significant positive correlations with teacher ratings of impulsivity, significant negative correlations with ratings of academic achievement, and little relationship to rated sociability. Videogame use also proved positively related to other social activities and to microcomputer use.  相似文献   
999.
To facilitate the classroom and workshop integration of three autistic clients, we examined the feasibility of teaching them to respond appropriately without the continual presence of specially trained treatment providers. Within a multiple baseline design, a 4-step treatment process was implemented to promote durable responsive performance. Results indicated that the therapist could be removed from the treatment environment and that appropriate behavior could be successfully maintained in community settings with only infrequent and delayed contingencies.  相似文献   
1000.
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