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871.
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   
872.
S Gutstein 《Family process》1987,26(4):475-491
Concern for adolescents who act in dangerous, life-threatening ways has heightened dramatically in recent years. Many of these adolescents appear to come from nuclear families isolated from their kinship systems. Without the mediating effects of kin, the adolescent transition can become a major crisis. Kinship systems remain cohesive when members can reconcile their beliefs about essential aspects of family functioning with the demands for adaptation during major life transitions. Reconciliation is lost when members believe that kin can no longer be trusted to insure their well-being. Kinship fragmentation ensues as family members leave the field or are excluded. Isolated nuclear families then rapidly lose the resilience to respond to life transitions without resorting to extreme, maladaptive solutions. The Systemic Crisis Intervention Program (SCIP) uses the opportunity of the crisis precipitated by the adolescent's life-threatening behavior to alter family myths that have led to network fragmentation. Crisis teams mobilize and meet with kin in four-hour gatherings to foster reconciliation and kinship system reintegration.  相似文献   
873.
Chronic Illness and the Life Cycle:A Conceptual Framework   总被引:2,自引:0,他引:2  
This article provides a conceptual framework for thinking about the system created at the interface of chronic illness with the family life cycle. First, a psychosocial typology and time phases of illness schema is described as a necessary, preliminary step to create a common language that bridges the worlds of illness, individual, and family development. This schema organizes similarities and differences between diseases in a manner useful to psychosocial-developmental rather than biomedical inquiry. Then, drawing on several major life-cycle theories in the literature, key concepts (periods of transition, life-structure building and maintaining, centripetality, and centrifugality) are used in a complementary fashion to link these three lines of development. Equipped with these psychosocial languages, consideration is given to transgenerational aspects of illness, loss, and crisis, and the interwoven threads of illness, family, and individual development. Clinical vignettes are provided to highlight this conceptual framework.  相似文献   
874.
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   
875.
This study examined the effects of academic stress upon components of Type A behavior and cardiovascular reactivity. In a longitudinal design, heart rate and blood pressure responses to the Type A Structured Interview (SI) and additional laboratory challenges were measured in medical students at three points during an academic semester. Sessions 1 and 3 were scheduled during vacation periods; Session 2 took place during an intensive examination week. Results indicated that three “stylistic” components of Pattern A derived from the SI—loud and explosive speech, short response latency, and potential for hostility—increased significantly during the exam period. Similar increases achieved marginal significance for another stylistic component, rapid and accelerated speech. By contrast, global Type A assessments did not increase with academic demands. Cardiovascular reactivity was significantly but only moderately stable across the three sessions, showing less consistency than has been reported in previous research. In addition, there was little evidence in this study that cardiovascular reactivity was potentiated by academic stress or by Type A behavior. These results demonstrate the influence of naturalistic environmental factors on overt behavioral components that have recently been suggested as coronary risk factors. Therefore, it is advisable for future experimental and epidemiological research to examine the social and environmental context in which these behaviors occur.  相似文献   
876.
The evolution of a therapy group for hospitalized Vietnam veterans with post-traumatic stress disorder (PTSD) and related symptomatology is described. The literature on group treatment for this population is briefly reviewed and discussed in relation to an inpatient psychiatry setting. The prevailing conditions at the time of group inception are recalled along with the initial goals of the therapeutic intervention. Problems encountered are also discussed, along with the changes made in response to these identified difficulties. The results of three and one-half years of experience with this group are described in detail.The authors would like to thank Cynthia Sturm, Ph.D. for her helpful editorial assistance.  相似文献   
877.
We evaluated the effects of aversive taste treatment of thumb sucking on untreated trichotillomania (habitual hair pulling) in two children who chronically pulled their hair and sucked their thumbs. A combination of withdrawal and nonconcurrent multiple baseline designs showed that, concomitant with the successful treatment of thumb sucking, hair pulling was also eliminated. The results suggest an efficient method for changing behaviors that are difficult to treat directly.  相似文献   
878.
879.
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   
880.
A program using behavioral practice, assertiveness training, and social and contrived reinforcers was developed to establish and maintain automobile safety belt use by young children. Sixteen children (ages 4.8 to 7 years) who never used their safety belts during a 5-day preexperimental observation period were randomly assigned to two groups of eight each. A multiple baseline design across groups was used to evaluate the effectiveness of the training program. During the 8-day baseline period for Group 1, no children used their safety belts when unobtrusively observed while being driven from school. During the 26-day intervention period, the children were buckled up on 96% of the observations. Follow-up probes conducted 2–3 months after program discontinuance found safety belt use to range from 86% to 100%. For Group 2, the 14-day baseline safety belt use averaged 6% and increased to a mean of 81% during the 20-day training and maintenance program. Follow-up probes 2–3 months later found safety belt use to occur during 75% to 96% of the observations. Parent questionnaires indicated the generalizability and social validity of the program.  相似文献   
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