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971.
R A Bauman T G Raslear S R Hursh D Shurtleff L Simmons 《Journal of the experimental analysis of behavior》1996,65(2):401-422
Three experiments were conducted to study the effect of an imperfect substitute for food on demand for food in a closed economy. In Experiments 1 and 2, rats pressed a lever for their entire daily food ration, and a fixed ratio of presses was required for each food pellet. In both experiments, the fixed ratio was held constant during a daily session but was increased between sessions. The fixed ratio was increased over a series of daily sessions once in the absence of concurrently available sucrose and again when sucrose pellets were freely available. For both series, increases in the fixed ratio reduced food intake, but body weight was reduced only in the no-sucrose condition. In the sucrose condition, body weight and total caloric intake (sucrose plus food) were relatively unaffected by increases in the fixed ratio. At all fixed ratios, food intake was proportionally reduced by the intake of sucrose. In Experiment 3, monkeys obtained food or saccharin by pressing keys; the fixed ratio of presses per food pellet was increased once when tap water was each monkey's only source of fluid, again when each monkey's water was sweetened with saccharin, and a third time when each monkey had concurrent access to the saccharin solution and plain water. Increases in the fixed ratio, but not the intake of the saccharin solution, reduced each monkey's food intake. Because neither rats' sucrose nor monkeys' saccharin intakes affected the slope of the respective demand curves for food, monkeys and rats increased their daily output of presses and thereby defended their daily intake of those complementary elements of food. However, sucrose reduced rats' food intake. The relative constancy of body weight and total caloric intake in the sucrose condition is consistent with the possibility that rats tended to regulate caloric intake. 相似文献
972.
The purpose of this study was to learn more about the role of religious beliefs and practices in bereavement. Subjects were 312 adults each bereaved approximately one year. They were interviewed at the rate of about 50 per year over a 6 year period. Conclusions include: a) The opportunity to say goodbye to the deceased was significantly related to positive coping and outlook; (b) 47% of our subjects reported contact with the deceased following the death but such contact was not related to coping or outlook; c) grieving people are much more likely to turn to women than men for help; d) 77% said their religious beliefs were of considerable help in their grief. 相似文献
973.
974.
David A. Abwender Kimberly S. Trinidad Kathy R. Jones Peter G. Como Enid Hymes Roger Kurlan 《Brain and language》1998,62(3):455-464
Developmental stuttering (DS) may be related to the extrapyramidal motor system and shares many clinical similarities with Tourette's syndrome (TS), which is widely believed to be associated with extrapyramidal dysfunction. Twenty-two stutterers were examined for neuropsychiatric features commonly seen in TS, including tics, obsessive-compulsive behaviors (OCB), and attention deficit disorders. Eleven stutterers displayed motor tics, and symptoms of OCB were observed at rates similar to those seen in persons with TS. Few stutterers demonstrated significant attentional deficits. Findings are consistent with models suggesting extrapyramidal involvement in DS and raise the possibility that DS and TS are pathogenetically related. 相似文献
975.
Gregory M. Herek J. Roy Gillis Eric K. Glunt Jeffrey Lewis David Welton John P. Capitanio 《American journal of community psychology》1998,26(5):705-743
The importance of using culturally sensitive educational materials in HIV-related interventions with racial and ethnic minority groups is widely recognized. However, little empirical research has been conducted to assess the relative effectiveness of different techniques for creating culturally sensitive AIDS educational videos. Two field experiments with three samples of African American adults (N = 174, 173, and 143) were conducted to assess how source characteristics (race of communicator), message characteristics (multicultural message vs. culturally specific message), and audience characteristics (racial distrust and AIDS-related distrust) influence proximate (perceptions of the message's credibility and attractiveness) and distal (AIDS-related attitudes, beliefs, and behavioral intentions) output variables for AIDS educational videos. In Study 1, an AIDS video with a culturally specific message was rated as more credible, more attractive, and of higher quality than was a video with a multicultural message. The multicultural message was rated less favorably when delivered by a White announcer than when the announcer was Black. In Study 2, the same pattern was replicated with a second community sample and a campus-based sample. Study 2 also indicated that a multicultural message might be more effective if delivered in a culturally specific context, namely, after audience members watch a culturally specific video. Minimal changes were observed in distal outcome variables. It is argued that influencing proximate output variables is necessary, though not sufficient, for effecting long-term change in AIDS-related attitudes, beliefs, and behaviors. 相似文献
976.
Mothers of problem and nonproblem toddlers rated videotapes of their own and unfamiliar children's behavior. They classified the behaviors as positive, negative, or neutral, and evaluated the intensity of the positive or negative behaviors. Ratings did not differ by problem status; however, all mothers classified their own children's behavior as less negative than did an independent observer. Mothers also evaluated all children's negative behavior as less aversive than did the observer. Finally, mothers mistakenly classified less of their own children's behavior as negative and more as positive when compared to their biases in classifying unfamiliar children's behavior. 相似文献
977.
Michael G. Sawyer David L. Streiner Peter Baghurst 《Journal of abnormal child psychology》1998,26(6):407-414
This study examined the effect of parental distress on mothers' and fathers' reports of children's emotional and behavioral problems. The subjects were the parents of 696 children aged 10 to 11 or 14 to 15 years living in two-parent families in the community. The study utilized an extended version of the model previously employed by Fergusson, Lynskey, and Horwood (1993) to examine the impact of maternal depression on mothers' reports of children's behavior. In the present study, the extended model was used to assess the impact of distress on reports of childhood externalizing and internalizing problems obtained from both mothers and fathers. The results suggested that distress had little influence on mothers' or fathers' reports of childhood behavior problems. It is concluded that in community studies the size of any bias in mothers' and fathers' reports of childhood behavior problems due to parental distress is likely to be very small and of little clinical significance. 相似文献
978.
David Schwartz Kenneth A. Dodge John D. Coie Julie A. Hubbard Antonius H. N. Cillessen Elizabeth A. Lemerise Helen Bateman 《Journal of abnormal child psychology》1998,26(6):431-440
A contrived play group procedure was utilized to examine the behavioral and social-cognitive correlates of reactive aggression, proactive aggression, and victimization via peers. Eleven play groups, each of which consisted of six familiar African-American 8-year-old boys, met for 45-min sessions on five consecutive days. Social-cognitive interviews were conducted following the second and fourth sessions. Play group interactions were videotaped and examined by trained observers. High rates of proactive aggression were associated with positive outcome expectancies for aggression/assertion, frequent displays of assertive social behavior, and low rates of submissive behavior. Reactive aggression was associated with hostile attributional tendencies and frequent victimization by peers. Victimization was associated with submissive behavior, hostile attributional bias, reactive aggression, and negative outcome expectations for aggression/assertion. These results demonstrate that there is a theoretically coherent and empirically distinct set of correlates associated with each of the examined aggression subtypes, and with victimization by peers. 相似文献
979.
Sydney S. Zentall Arlene M. Hall David L. Lee 《Journal of abnormal child psychology》1998,26(5):335-343
Mirrors have been used to focus attention to aspects of the self (e.g., to known strategies, standards). We hypothesized that this could be important for students with hyperactivity/inattention, who typically direct attention outward to external novelty. In this study, we administered a partially solvable word puzzle to 43 middle school students, with and without hyperactivity/inattention, in the presence and absence of a mirror, counterbalanced for condition and form order. Differences between students with hyperactivity/inattention and comparisons in accuracy were found only in the no mirror condition. Furthermore, the beneficial effect of the mirror for children with hyperactivity/inattention was most pronounced for those who looked at the mirror. Findings were interpreted in terms of their potential to remedy the production deficits of these children. 相似文献
980.
Norman T. Feather Margaret A. Norman Anthony Worsley 《Journal of applied social psychology》1998,28(7):639-656
This study investigated relations between values and the attractiveness and choice of food in different contexts for a sample of 464 participants who completed a mail survey distributed in 12 supermarkets in metropolitan Adelaide, South Australia. Participants responded to 5 hypothetical scenarios describing situations, each of which presented 2 alternatives relating to the presentation or consumption of different foods. Participants also completed the Schwartz Value Survey (Schwartz, 1992). Results showed that measures of the attractiveness (or valence) of each alternative and choice of alternative were related to specified value types for some scenarios, depending on context and structural relations among the value types engaged by each alternative. Results also implied that choice of alternative was mediated by the valences. 相似文献