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961.
In daily activities, humans must attend and respond to a range of important items and inhibit and not respond to unimportant distractions. Our current understanding of these processes is largely based on perceptually simple stimuli. This study investigates the interaction of conceptual-semantic categorization and inhibitory processing using Event Related Potentials (ERPs). Participants completed three Go–NoGo tasks that increased systematically in the degree of conceptual-semantic information necessary to respond correctly (from single items to categories of objects and animals). Findings indicate that the N2 response reflects inhibitory processing but does not change significantly with task difficulty. The P3 NoGo amplitude, on the other hand, is attenuated by task difficulty. Further, the latency of the peak of the P3 NoGo response elicited by the most difficult task is significantly later than are the peaks detected during performance of the other two tasks. Thus, the level of complexity of conceptual-semantic representations influences inhibitory processing in a systematic way. This inhibition paradigm may be a key for investigating inhibitory dysfunction in patient populations.  相似文献   
962.
Shared decision making between patients and providers is becoming increasingly common, particularly when there is no clear preferred course of action. As a result, decision aids are being adopted with growing frequency and have been applied to many medical decision-making issues. One such issue where there is uncertainty is breast cancer risk management among BRCA1/BRCA2 carriers. We present the development of a CD-ROM decision aid to facilitate risk management decision making in this population. Our decision aid was developed with the intention of providing it through a randomized clinical trial. The CD-ROM is a multimedia, interactive intervention which provides information about breast cancer, risks associated with BRCA1 and BRCA2 mutations, risk management options for hereditary breast cancer, and a breast cancer risk management decision aid. The goal of this CD-ROM, offered as an adjunctive intervention, is to reduce decisional conflict and psychological distress and improve comprehension of risk information, decisional satisfaction, medical adherence, and quality of life for this population of women at increased risk for breast cancer.  相似文献   
963.
Alpha-2 adrenoceptors (alpha(2)-ARs) are critically involved in regulating neurotransmitter release from sympathetic nerves and neurons and play an important role in the regulation of awareness, arousal and vigilance. In our recent study, dexmedetomidine, a full alpha(2)-AR agonist, produced antiaggressive effects in the social conflict test in mice at doses that were twice smaller than those producing sedation. The aim of this study was to ascertain antiaggressive effect of a novel drug naphthylmedetomidine, with a more selective alpha(2)-AR activity. Behavioral effects of naphthylmedetomidine (150-1200 microg/kg i.p.) were studied in the activity cage and in the social conflict tests in mice. Naphthylmedetomidine dose dependently decreased aggressive behavior during social conflict in aggressive mice with significant reduction already at the lowest doses tested (150 microg/kg), whereas locomotion and social investigation were significantly decreased only after four times bigger dose of naphthylmedetomidine (600 microg/kg) in aggressive mice. Naphthylmedetomidine had no effect on aggression in nonaggressive mice. Naphthylmedetomidine reduced locomotion in the activity cage significantly only at the highest doses tested (600 and 1200 microg/kg), and this effect was only partially reversed by administration of high doses of an alpha-2 antagonist atipamezole (3 and 10 mg/kg). In nonaggressive mice, the difference between the dose reducing dominant social behavior (social investigation) and locomotion (150 and 300 microg/kg, respectively) was smaller than in aggressive mice. In conclusion, naphthylmedetomidine showed a very strong and selective antiaggressive effect in aggressive mice, which was devoid of locomotion-inhibiting/sedative effect. This study suggests that naphthylmedetomidine may have clinical potential as antiaggressive drug.  相似文献   
964.
N2pc与空间选择性注意密切相关, 反映了一种对当前任务相关刺激的注意分配过程。N2pc自我特性的研究主要涉及理论解释、测量方法、源定位以及影响因素等方面, 而其实验范式主要有视觉搜索和视觉短时记忆搜索两种范式。以N2pc为指标的研究主要分为与视觉空间注意相关的基础性研究和应用性扩展研究。今后N2pc的研究应该在不断深入细化自身特性研究、做好基础性研究的同时, 更多的向应用性扩展研究拓展。  相似文献   
965.
本研究探讨了利他和利己动机驱动下的欺骗行为在行为和神经机制上的差异,及不同强度利他动机之间的差异。行为结果发现,个体在利己动机下相比于利他动机下会更多地撒谎,且在高利他与低利他动机下的撒谎程度显著正相关。ERP结果发现,在利己动机下,有机会撒谎比无机会撒谎条件诱发了更大的N2和更小的P3波幅;而在高低利他动机下,两种条件的波幅差异不显著。结合行为和ERP结果,得出这样的结论:基于利他动机与基于利己动机的欺骗行为存在本质不同,而基于不同水平利他动机的欺骗行为之间只存在量的差异。  相似文献   
966.
脑可塑性指人脑会因为环境刺激、认知需求和行为经验而产生功能或结构改变。近10年来的单双语者对比和语言训练研究结果表明, 不论儿童、青年或老年人, 第二语言学习和使用都能改变其脑运行模式并带来相应结构变化, 包括灰质(GM)体积和白质(WM)密度增加, 且长期持续的双语经验还能形成认知优势, 帮助抵制由老化导致的负面认知影响。基于脑可塑性概念及其研究证据, 从双语经验与语言训练两方面, 对比分析了长期和短期第二语言学习引起脑功能或结构变化及其内在机制, 并对未来相关研究进行了展望。  相似文献   
967.
968.
Guided by a process model of parenting and the integrative model, this study examined sources of emotional support (i.e., partner, maternal, paternal) as related to stress and satisfaction resulting from the parenting role in a sample of Mexican‐origin young adult parents who participated in the National Longitudinal Study of Adolescent to Adult Health (Add Health) during Wave IV. Participants were male and female parents (26–35 years of age; 59% female; N = 737) who had children and a partner. Results from structural equation modeling revealed support from mothers as salient; high levels of maternal support were associated with high levels of parenting satisfaction. Tests of indirect effects suggested that parenting satisfaction played an intervening role in the link between maternal support and parenting stress. The pattern of results held across levels of linguistic acculturation but varied by gender. Understanding the mechanisms that predict parenting stress and satisfaction within the Mexican‐origin population may help in the identification of culturally sensitive intervention strategies.  相似文献   
969.
There is growing recognition that caring for a patient with schizophrenia often results in high levels of perceived burden and poorer overall mental health for caregivers. A quantitative cross‐sectional design and standardized instruments were used to collect data from 355 primary caregivers of adults in outpatient care with schizophrenia in China. Structural equation modeling was used to examine the association between caregiver burden and mental health among primary caregivers and whether this association is influenced by personality, coping style, and family functioning, based on a diathesis–stress perspective. Goodness‐of‐fit indices (χ2/df = 1.406, GFI = 0.919, CFI = 0.957, etc.) confirmed that the modified model fit the data well. In line with the diathesis–stress model, and with this study's hypotheses, we found that caregiver burden was significantly related to mental health outcomes directly. The final model showed that personality traits, coping style, and family function influenced the relationship between caregiver burden and mental health. The neuroticism personality traits have a direct effect on caregiver burden and family functioning in this sample. Coping style had a direct effect on the caregiver burden, and family functioning had a direct effect on the caregiver burden. Our final model about primary caregivers can be applied clinically to predict mental health outcomes from caregiver burden.  相似文献   
970.
This study examined the effects of observation‐based supervision Building Outcomes with Observation‐Based Supervision of Therapy (BOOST therapists = 26, families = 105), versus supervision as usual (SAU therapists = 21, families = 59) on (a) youth externalizing behavior problems and (b) the moderating effects of changes in family functioning on youth externalizing behaviors for adolescents receiving Functional Family Therapy (FFT). Exploratory analyses examined the impact of supervision conditions on youth internalizing problems. In 8 community agencies, experienced FFT therapists (= 1.4 years) received either BOOST or SAU supervision in a quasi‐experimental design. Male (59%) or female (41%) adolescents were referred for the treatment of behavior problems (e.g., delinquency, substance use). Clients were Hispanic (62%), African American (19%), Non‐Hispanic White (12%), or Other (7%) ethnic/racial origins. Therapists (female, 77%) were Hispanic 45%, African American (19%), White Non‐Hispanic (30%), or other (4%) ethnic/racial backgrounds. Analyses controlled for the presence or absence of clinically elevated symptoms on outcome variables. Clinical outcomes were measured at baseline, 5 months, and 12 months after treatment initiation. Clients with externalizing behavior above clinical thresholds had significantly greater reductions in problem behaviors in the BOOST versus the SAU conditions. Clients below thresholds did not respond differentially to conditions. Supervisors in BOOST had more experience with the FFT model; as such, the observed results may be a result of supervisor experience. The BOOST supervision was associated with improved outcomes on problem behaviors that were above clinical thresholds. The findings demonstrate the importance of addressing client case mix in implementation studies in natural environments.  相似文献   
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