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961.
Effects of anorectic drugs on food intake under progressive-ratio and free-access conditions in rats 下载免费PDF全文
The effects of two anorectic drugs, dexfenfluramine and phentermine, on food intake under different food-access conditions were examined. Experiment 1 compared the effects of these drugs on food intake under a progressive-ratio (PR) schedule and free-access conditions. Dexfenfluramine decreased food intake under both conditions, but the doses required to decrease intake under free-access conditions were higher than those required to reduce intake under the PR condition. Intermediate doses of phentermine sometimes increased breaking points, and higher doses decreased them. Phentermine decreased food intake at the same doses under both access conditions. Thus the potency of dexfenfluramine, but not phentermine, to decrease food-maintained behavior depended upon the food-access condition. Experiment 2 used a novel mixed progressive-ratio schedule of food delivery to study the duration of drug effects. Sessions consisted of five components separated by 3-hr timeouts. The ratio requirement reset at the beginning of each component and a new breaking point was obtained. Both dexfenfluramine and phentermine dose-dependently decreased breaking points early in the session. In some rats, compensatory increases in breaking point were observed. That is, breaking points later in the session increased over control levels, resulting in no change in the total number of food pellets earned for the session compared to control. The present findings suggest that the effects of some anorectic drugs depend upon the access conditions for food; increasing the effort to obtain food may enhance their ability to decrease food-maintained behavior. 相似文献
962.
The authors examined the extent to which performance on interpersonal cognitive problem-solving (ICPS) tasks is affected by whether the goals within the dilemmas to be addressed are sex typed. Fifty children, aged 7-8 years old, were tested for the core ICPS skills of Alternative Solutions Thinking (AST) and Consequential Thinking (CT) on a series of 8 social problem-solving tasks, 4 having goals characteristically more attractive to boys and 4 with goals more attractive to girls. A 2 x 2 MANOVA was used to compare the performances of boys and girls on each set of sex-typed tasks with the 3 dependent variables of liking for the tasks, number of alternative solutions suggested, and the number of consequences anticipated. As expected, liking for the tasks was higher if the activities were characteristically associated with the participant's own gender (p < .001), although the different tasks did not produce any significant gender differences in the numbers of AST or CT suggestions they prompted. Gender differences in children's peer relationships were considered, and the implications of these results for the format of ICPS interventions are noted. 相似文献
963.
Disrupting feedback processing interferes with rule-based but not information-integration category learning 总被引:4,自引:0,他引:4
The effect of a sequentially presented memory scanning task on rule-based and information-integration category learning was investigated. On each trial in the short feedback-processing time condition, memory scanning immediately followed categorization. On each trial in the long feedback-processing time condition, categorization was followed by a 2.5-sec delay and then memory scanning. In the control condition, no memory scanning was required. Rule-based category learning was significantly worse in the short feedback-processing time condition than in the long feedback-processing time condition or control condition, whereas information-integration category learning was equivalent across conditions. In the rule-based condition, a smaller proportion of observers learned the task in the short feedback-processing time condition, and those who learned took longer to reach the performance criterion than did those in the long feedback-processing time or control condition. No differences were observed in the information integration task. These results provide support for a multiple-systems approach to category learning and argue against the validity of single-system approaches. 相似文献
964.
College students generated autobiographical memories from distinct emotional categories that varied in valence (positive vs. negative) and intensity (high vs. low). They then rated various perceptual, cognitive, and emotional properties for each memory. The distribution of these emotional memories favored a vector model over a circumplex model. For memories of all specific emotions, intensity accounted for significantly more variance in autobiographical memory characteristics than did valence or age of the memory. In two additional experiments, we examined multiple memories of emotions of high intensity and positive or negative valence and of positive valence and high or low intensity. Intensity was a more consistent predictor of autobiographical memory properties than was valence or the age of the memory in these experiments as well. The general effects of emotion on autobiographical memory properties are due primarily to intensity differences in emotional experience, not to benefits or detriments associated with a specific valence. 相似文献
965.
OBJECTIVES: To determine the extent to which transition planning and community service would predict lower levels of recidivism among mentally ill juvenile offenders. DESIGN: Review of legal, medical and social service records including examination of 3-month period following community release. PARTICIPANTS: Juvenile offenders incarcerated for 6 months or more (N = 44) transitioning to community. MEASURES: Child and Adolescent Functional Assessment Scale (CAFAS), sum of different documented pre- and post-release discharge planning contacts, documented community service contacts. OUTCOMES: Re-offense during the first year post-release. RESULTS: Documented community service contacts in the 3 months following discharge were rare for mental health (20.5%), substance abuse (38.6%), financial assistance (29.5%), and school placement (34.1%). The average number of different pre-release and post-release discharge planning contacts was also low, M(SD)=1.86(1.68) and M(SD)= 2.34(1.71) respectively. Post-release discharge planning and the receipt of financial assistance and mental health services were all associated with lower levels of reoffending. CONCLUSIONS: Community transition planning, including the coordination and provision of community services, is an essential component of community reintegration for juvenile offenders and is associated with lower rates of recidivism during the first year post-discharge. 相似文献
966.
Many gay, lesbian, and bisexual adults report a period of childhood sexual questioning--an uneasy questioning of their heterosexuality brought on by same-sex attractions and motivating same-sex sexual exploration. This article evaluates hypotheses about the correlates, causes, and consequences of childhood sexual questioning. Participants were 182 children in the 4th through 8th grades. Compared with children more confident in their heterosexuality, sexual-questioning children reported more impaired self-concepts, fewer same-sex-typed attributes (but not more cross-sex-typed attributes), a greater sense of feeling different from same-sex others, and lesser satisfaction with their gender assignment. Short-term longitudinal analyses indicated that sexual questioning is more likely a determinant than a consequence of these correlated variables. However, influences of sexual questioning on these outcomes were small. 相似文献
967.
Wolfe DA Wekerle C Scott K Straatman AL Grasley C 《Journal of abnormal psychology》2004,113(3):406-415
Three mediators of the relationship between childhood maltreatment and dating violence perpetration during midadolescence (i.e., trauma-related symptoms, attitudes justifying dating violence, and empathy and self-efficacy in dating relationships) were tested over 1 year with a sample of students from 10 high schools (N = 1,317). Trauma-related symptoms had a significant cross-time effect on predicting incidents of dating violence for both boys and girls. Attitudes and empathy and self-efficacy did not predict dating violence over time, although they were correlated with such behavior at both time points. Child maltreatment is a distal risk factor for adolescent dating violence, and trauma-related symptoms act as a significant mediator of this relationship. The importance of longitudinal methodology that separates correlates from predictors is discussed. 相似文献
968.
Difficulties in comprehending causal relations among children with ADHD: the role of cognitive engagement 总被引:5,自引:0,他引:5
Pugzles Lorch E Eastham D Milich R Lemberger CC Polley Sanchez R Welsh R van den Broek P 《Journal of abnormal psychology》2004,113(1):56-63
The present study examined whether time spent in long looks (i.e., >or=15 s), an index of cognitive engagement, would account for differences between children with attention deficit hyperactivity disorder (ADHD) and comparison children in understanding causal relations. Children viewed two televised stories, once in the presence of toys and once in their absence. Dependent variables were visual attention and questions tapping factual information and causal relations. Comparison children answered significantly more causal relations questions than did the children with ADHD, but only in the toys-present condition. Four lines of evidence revealed that the difficulties children with ADHD had in answering causal relations questions in the toys-present condition could be linked specifically to this group's decreased time spent in long looks. 相似文献
969.
Cole DA 《Journal of abnormal psychology》2004,113(1):3-9
This article introduces a special section on the use of taxometrics to examine the categorical versus the dimensional structure of various forms of psychopathology. Paving the way into the special section, this introduction briefly describes 3 taxometric methods--mean above minus below a sliding cut (MAMBAC), maximum covariation (MAXCOV), and maximum eigenvalue (MAXEIG)--and discusses possible threats to statistical conclusion validity that often emerge when such techniques are applied in psychopathology research. 相似文献
970.
Schmitt DP Alcalay L Allik J Angleitner A Ault L Austers I Bennett KL Bianchi G Boholst F Borg Cunen MA Braeckman J Brainerd EG Caral LG Caron G Casullo MM Cunningham M Daibo I De Backer C De Souza E Diaz-Loving R Diniz G Durkin K Echegaray M Eremsoy E Euler HA Falzon R Fisher ML Foley D Fry DP Fry S Ghayur MA Golden DL Grammer K Grimaldi L Halberstadt J Haque S Herrera D Hertel J Hoffmann H Hooper D Hradilekova Z Hudek-Kene-evi J Jaafar J Jankauskaite M Kabangu-Stahel H Kardum I Khoury B 《Journal of personality and social psychology》2004,86(4):560-584