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971.
972.
Laboratory rats were rewarded for face-washing, rearing, or scratching by being given the opportunity to press retractable levers for food reward. Yoked control animals received the same number of lever presentations and food rewards, but did not have to face-wash, rear, or scratch to obtain the levers. The experimental animals showed increases in number of bouts of reinforced target behavior above control levels, and the total amount of time spent face-washing increased when a 1.5-sec criterion for reinforced bout length was introduced. The activities in this experiment were made to serve a discriminative as well as an instrumental function, since the cue to tell the rat which lever to press for reward when the levers were presented was the activity that the rat had engaged in to obtain lever presentation. In two separate experiments high levels of discrimination between behaviors were obtained. Discrimination was worse following scratching than after other actions, and scratching also showed relatively poor instrumental conditioning. The relationship between Pavlovian and instrumental conditioning processes in this situation is discussed. 相似文献
973.
A mailed survey was conducted to determine differential stereotypes concerning Men, Women, and Successful Managers. A moderately high degree of similarity was found between stereotypes of Men and Managers, but none between Men and Women nor Women and Managers for male respondents. Female respondents perceived a moderately high similarity between Men and Managers and a slight degree of similarity between Women and both Men and Managers. 相似文献
974.
To determine whether manual incoordination is caused by attention deficit or not, we used an accuracy drawing task as a primary task in dual-task and resistance-to-distraction studies, and examined if thus measured attention could differentiate inattention (IA) and combined (CO) subtypes of ADHD. The secondary tasks and distractions failed to lower the primary task performance in IA, CO and control groups. We also compared the impairment scores of the accuracy drawing tasks from the Movement Assessment Battery for Children [Henderson, S. E., & Sugden, D. A. (1992). Movement assessment battery for children. London: Psychological Corporation.] between the groups with attention deficit hyperactivity disorder (ADHD) and/or developmental coordination disorder-inaccurate drawing type (DCD-ID). There were no group differences in the impairment score between the control and the ADHD groups, and between ADHD and ADHD plus DCD-ID groups. We concluded that inaccurate drawing is not caused by attention deficit, but that it is a manifestation of a motor deficit as a separate entity from attention deficit. 相似文献
975.
Prenatal paternal depression 总被引:2,自引:0,他引:2
Field T Diego M Hernandez-Reif M Figueiredo B Deeds O Contogeorgos J Ascencio A 《Infant behavior & development》2006,29(4):579-583
Prenatal depressive symptoms, anxiety, anger and daily hassles were investigated in 156 depressed and non-depressed pregnant women and their depressed and non-depressed partners (fathers-to-be). Depressed versus non-depressed fathers had higher depression, anxiety and daily hassles scores. Although the pregnant women in general had lower anxiety, anger and daily hassles scores than the men, the scores on the measures for depressed fathers and depressed mothers did not differ. Paternal depression appeared to have less effect than maternal depression on their partners’ scores. However, the similarity between the scores of depressed mothers and depressed fathers highlights the importance of screening for depression in fathers-to-be as well as mothers-to-be during pregnancy. 相似文献
976.
It has been suggested that some of the addictive potential of psychostimulant drugs of abuse such as amphetamine may result from their ability to enhance memory for drug-related experiences through actions on memory consolidation. This experiment examined whether amphetamine can specifically enhance consolidation of memory for a Pavlovian association between a neutral conditioned stimulus (CS-a light) and a rewarding unconditioned stimulus (US-food), as Pavlovian conditioning of this sort plays a major role in drug addiction. Male Long-Evans rats were given six training sessions consisting of 8 CS presentations followed by delivery of the food into a recessed food cup. After the 1st, 3rd, and 5th session, rats received subcutaneous injections of amphetamine (1.0 or 2.0 mg/kg) or saline vehicle immediately following training. Conditioned responding was assessed using the percentage of time rats spent in the food cup during the CS relative to a pre-CS baseline period. Both amphetamine-treated groups showed significantly more selective conditioned responding than saline controls. In a control experiment, there were no differences among groups given saline, 1.0 or 2.0 mg/kg amphetamine 2 h post-training, suggesting that immediate post-training amphetamine enhanced performance specifically through actions on memory consolidation rather than through non-mnemonic processes. This procedure modeled Pavlovian learning involved in drug addiction, in which the emotional valence of a drug reward is transferred to neutral drug-predictive stimuli such as drug paraphernalia. These data suggest that amphetamine may contribute to its addictive potential through actions specifically on memory consolidation. 相似文献
977.
Brosco JP Seider MI Dunn AC 《Mental retardation and developmental disabilities research reviews》2006,12(4):262-269
Universal newborn screening programs for metabolic disorders are typically described as a triumph of medicine and public policy in the US over the last 50 years. Advances in science and technology, including the Human Genome Project, offer the opportunity to expand universal newborn screening programs to include many additional metabolic and genetic conditions. Although the benefits of such screening programs appear to outweigh their costs, some critics have claimed that historical examples of inadvertent harm ensuing from false-positive screening results and subsequent inappropriate medical treatment should make us wary of expanding universal newborn screening. In this essay, we report the results of a review of the published literature to assess whether the extension of screening from at risk populations to all newborns led to substantial morbidity and mortality from misguided medical treatment. We provide a historical overview of universal newborn screening programs in the United States, and then focus on six early NBS programs: congenital hypothyroidism, phenylketonuria, congenital adrenal hyperplasia, galactosemia, sickle cell disease, and maple syrup urine disease. Our comprehensive search of published sources did not reveal a widespread problem of harm ensuing from medical treatment of children with false positive screening test results. 相似文献
978.
Psychological resilience after disaster: New York City in the aftermath of the September 11th terrorist attack 总被引:2,自引:0,他引:2
Research on adult reactions to potentially traumatic events has focused almost exclusively on posttraumatic stress disorder (PTSD). Although there has been relatively little research on the absence of trauma symptoms, the available evidence suggests that resilience following such events may be more prevalent than previously believed. This study examined the prevalence of resilience, defined as having either no PTSD symptoms or one symptom, among a large (n= 2,752) probability sample of New York area residents during the 6 months following the September 11th terrorist attack. Although many respondents met criteria for PTSD, particularly when exposure was high, resilience was observed in 65.1% of the sample. Resilience was less prevalent among more highly exposed individuals, but the frequency of resilience never fell below one third even among the exposure groups with the most dramatic elevations in PTSD. 相似文献
979.
The purpose was to test the applicability of the Scale of Athlete Satisfaction for Greek swimmers and to assess sex and sport-related differences for swimers' mean satisfaction. The sample of 351 Greek swimmers comprised 186 males and 165 females competing in five categories of the National Swimming Championhip in Greece. Their mean age was 16 yr. (SD=2; range 13 to 28 years). A confirmatory factor analysis supported the factorial validity of the scale. Analysis indicated that sex, weekly practice schedule, and sport experience differentiated facets of satisfaction among these swimmers. This scale is reliable and valid for measuring athletes' satisfaction with individual sports. 相似文献
980.
Reynolds SK Lindenboim N Comtois KA Murray A Linehan MM 《Suicide & life-threatening behavior》2006,36(1):19-34
The purpose of this study was to examine patterns of self-reported suicidality and distress during research assessments in a sample of 63 women meeting criteria for borderline personality disorder and current and chronic suicidality. The risk management protocol we used during the two-year study period (University of Washington Risk Assessment Protocol; UWRAP) is described. Results indicated that changes in suicidality following assessments were small and relatively infrequent, and were just as likely to reflect decreases in suicidality as increases (17.5% versus 16.4% of sessions, respectively). Further, longitudinal analyses indicated that changes in suicidality became increasingly rare over the course of the 2-year study. Ratings of distress were more changeable than suicidality, underscoring the need for separate measurement of these constructs when assessing risk. With the aid of the UWRAP, our assessors judged 15 participants as high-risk status in 28 assessment sessions (3.7% of all sessions). In comparison to the rest of the sample, these individuals were of significantly greater clinical severity as measured by the HRSD 17-item, GAF scores, number and severity of previous suicide attempts, and number of previous psychiatric hospitalizations. Low-intensity risk intervention strategies (e.g., validating participant's feelings) were typically sufficient to reduce risk in these participants. Overall, our findings indicate that research with highly suicidal individuals can be done safely with the use of well-trained assessors and an appropriate crisis management protocol. 相似文献