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121.
Recent research has indicated that the pro-inflammatory cytokines, particularly interleukin-1beta (IL-1beta), can affect learning and memory. We injected male Sprague-Dawley rats with IL-1beta (1.0, 3.0, or 6.0 microg/kg, i.p.) or saline vehicle, 24h before a single 4-h session of leverpress escape/avoidance conditioning. No effect of IL-1beta at any dose was observed in the number of escape responses across the 4-h session. However, subjects treated with the two lower doses (1.0 and 3.0 microg/kg) of IL-1beta performed more avoidance responses during the final hour of the 4-h session than the other two groups. Subjects treated with the highest dose of IL-1beta (6.0 microg/kg) did not differ from controls. Results are discussed in terms of the possible mechanisms behind the IL-1beta-induced enhancement of learning, as well as the observed dose-response relationship.  相似文献   
122.
Exposure to electrical current via industrial or residential accidents or lightning strikes is a serious and growing concern in today's medical community. The sequelae that result are referred to as electrical injury (EI) or lightning injury (LI). The relevant principles in electricity are reviewed with particular attention given to their damaging capabilities on the body. Specific neuropsychological, psychiatric, and neurological signs and symptoms as well as objective measures of psychological and neuropsychological functioning and brain imaging in victims of EI and LI, are reviewed from past research. Important issues relevant to researchers in the field are discussed. Finally, the role that neuropsychology might play in this area is outlined.  相似文献   
123.
Studies of language impairments in patients with Alzheimer's disease have often assumed that impairments in linguistic working memory underlie comprehension deficits. Assessment of this hypothesis has been hindered both by vagueness of key terms such as "working memory" and by limitations of available working memory tasks, in that many such tasks either seem to have little relationship to language comprehension or are too confusing or difficult for Alzheimer's patients. Four experiments investigated the usefulness of digit ordering, a new task assessing linguistic working memory and/or language processing skill, in normal adults and patients with probable Alzheimer's disease. The digit ordering task was shown to be strongly correlated with the degree of dementia in Alzheimer's patients. The task correlated with measures of language processing on which patients and normal controls performed differently. The results are interpreted as indicating that linguistic representations, linguistic processing, and linguistic working memory are intertwined, such that a deficit of one (e.g., working memory) cannot be said to "cause" a deficit in the other. The implications of this approach are explored in terms of task demands in comprehension and memory measures, and interpretation of previous results in the literature.  相似文献   
124.
In considering the influences of microsystems on adolescent substance use, familial and peer contexts have received the most extensive attention in the research literature. School and neighborhood settings, however, are other developmental contexts that may exert specific influences on adolescent substance use. In many instances, school settings are organized to provide educational services to students who share similar educational abilities and behavioral repertoires. The resulting segregation of students into these settings may result in different school norms for substance use. Similarly, neighborhood resources, including models for substance use and drug sales involvement, may play an important role in adolescent substance use. We briefly review literature examining contextual influences on adolescent substance use, and present results from two preliminary studies examining the contribution of school and neighborhood context to adolescent substance use. In the first investigation, we examine the impact of familial, peer, and school contexts on adolescent substance use. Respondents were 283 students (ages 13 to 18) from regular and special education classrooms in six schools. Although peer and parental contexts were important predictors of substance use, school norms for drug use accounted for variance in adolescent use beyond that explained by peer and parental norms. Data from a second study of 114 adolescents (mean age = 15) examines neighborhood contributions to adolescent substance use. In this sample, neighborhood indices did not contribute to our understanding of adolescent substance use. Implications for prevention are presented.  相似文献   
125.
The aim of this study was to determine whether word stem completion for novel associations between cue and target words was mediated by automatic unconscious memory processes or effortful memory processes under conscious control. This was done by applying full and divided attention conditions at test to stem completion, cued recall, and recognition, and by administering a questionnaire that probed the memory strategies used by subjects during the completion test. Divided attention had no effect on stem completion performance, but did reduce associative cued recall. Recognition performance was weakened overall by divided attention, but the associative effect was similar under both attention conditions. This suggested that novel associative word stem completion was mediated by automatic retrieval processes. However, the results of the questionnaire indicated that only subjects who attempted to remember the words from the study phase during the completion task showed any novel associative effect. It is concluded that novel association word stem completion and cued recall share automatic retrieval processes, which nevertheless give rise to the experience of remembering.  相似文献   
126.
This exploratory study uses qualitative methods to focus on the largely unexamined role of the grandfather and to examine men's experiences as grandfathers. We gathered information through both surveys and individual interviews to explore men's feelings and attitudes toward the grandfather role. Of the 51 grandfathers that completed a survey, 20 participated in interviews. Our examination of the data collected reveals the life lessons men teach their grandchildren. The grandfathers in this study expressed strong desires for purposeful involvement in their grandchildren's lives and indicated desires for transferring values to grandchildren and teaching interpersonal relationships. Through this involvement, they educate through life experiences and serve as mentors for their grandchildren. We suggest that this mentoring role makes a positive contribution to the lives of grandchildren and to the identity of grandfathers.  相似文献   
127.
Belief revision theory concerns methods for reformulating an agent's epistemic state when the agent's beliefs are refuted by new information. The usual guiding principle in the design of such methods is to preserve as much of the agent's epistemic state as possible when the state is revised. Learning theoretic research focuses, instead, on a learning method's reliability or ability to converge to true, informative beliefs over a wide range of possible environments. This paper bridges the two perspectives by assessing the reliability of several proposed belief revision operators. Stringent conceptions of minimal change are shown to occasion a limitation called inductive amnesia: they can predict the future only if they cannot remember the past. Avoidance of inductive amnesia can therefore function as a plausible and hitherto unrecognized constraint on the design of belief revision operators.  相似文献   
128.
This study used interpretative phenomenological analysis (IPA) to explore the lived experiences of five individuals diagnosed with obsessive-compulsive disorder (OCD) who underwent a group cognitive behavioral therapy (CBT) intervention program to address their symptoms. Two master themes were identified: experiences and processes of change and reflections on change. For all participants, the degree of group cohesion or connectedness they established with group members emerged as highly important in facilitating therapeutic progress. A number of technical elements of cognitive behavioral therapy (CBT) were also notable therapeutic factors, including questioning/rationalizing maladaptive interpretations about intrusions. However, the commonality of non-specific group processes as key features for subsequent therapeutic change prompts the need for further research in dynamics within CBT group interventions for OCD.  相似文献   
129.
Posttraumatic stress disorder (PTSD) and substance use disorder (SUD) commonly co-occur. Emerging research suggests that both distress tolerance and impulsivity may underlie this comorbidity. However, to our knowledge no studies have examined whether these 2 constructs predict outcome in PTSD-SUD treatment. The current study investigated whether pretreatment distress tolerance and impulsivity predicted posttreatment PTSD and cravings severity in a sample of 70 Veterans receiving concurrent treatment for PTSD and SUD in a residential day treatment program. Veterans completed measures of symptom severity before and after treatment. Results demonstrated that pretreatment distress tolerance predicted posttreatment PTSD severity while controlling for pretreatment PTSD. By contrast, pretreatment impulsivity was not predictive of posttreatment PTSD while controlling for pretreatment values. Neither distress tolerance nor impulsivity predicted posttreatment cravings severity. The findings support the notion that distress tolerance may help to explain the co-occurrence of PTSD and SUD and suggest that targeting this construct in PTSD-SUD treatment may be important for successful outcomes.  相似文献   
130.
This study examines perceived stress and its relationship to depressive symptoms, life changes and functional capacity in a large sample of individuals who are positive for the Huntington disease (HD) gene expansion but not yet diagnosed. Participants were classified by estimated proximity to HD diagnosis (far, mid, near) and compared with a non-gene-expanded comparison group. Persons in the mid group had the highest stress scores. A significant interaction between age and time since HD genetic testing was also found. Secondary analyses using data from a different data collection point and including a diagnosed group showed the highest stress scores in the diagnosed group. Possible explanations and implications are discussed.  相似文献   
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