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991.
Noise exclusion in spatial attention   总被引:5,自引:0,他引:5  
Precue validity affects the performance of perceptual tasks. These spatial attention effects have been variously attributed to facilitation of processing, capacity allocation, or noise reduction. We used a new attention-plus-external (stimulus)-noise paradigm and model to identify the mechanisms of attention in cue-validity paradigms. A new phenomenon is reported: a large effect of location cue validity in an orientation identification task that specifically occurs when the stimulus is embedded in external (environmental or stimulus) noise. This result identifies the mechanism of the effect as external-noise exclusion, distinguished from stimulus enhancement that manifests itself only in noiseless stimulus environments.  相似文献   
992.
In order to investigate if HPA functioning is altered with age, the present study was conducted. Fifteen healthy elderly men (60-76 years; mean age 66.5 +/- 1.48 yrs.) and 12 younger adults (20-29 years; mean age 25.6 +/- 0.77 yrs.) collected salivary free cortisol profiles after awakening for basal HPA activity. Then, all subjects were exposed to the "Trier Social Stress Test" (TSST). This psychosocial stress protocol consists of a free speech and a mental arithmetic task of 13 minutes duration performed in front of an audience. Beside the assessment of endocrine and cardiovascular responses to the stressful task ratings of depression, mood and perceived stressfulness were obtained. Results show that younger and elderly men had similar morning cortisol profiles after awakening with both groups showing the expected rise after awakening (P=0.004). The TSST induced significant increases in ACTH, total plasma cortisol, saliva free cortisol, and heart rates (all P<0.0001). Regardless of age, both age groups showed comparable endocrine response patterns when confronted with the stressor. However, cardiovascular responses were significantly higher in younger men compared to elderly men (P=0.03). Catecholamine data revealed significant norepinephrine and epinephrine increases due to the stressor (both P<0.0001) with a trend toward elevated norepinephrine levels in elderly men (P=0.058). In sum, the investigated basal and response parameters of HPA functioning neither support the idea of a reduced resilience in healthy aged humans nor do they appear to strengthen assumptions derived from the so called "glucocorticoid cascade hypothesis".  相似文献   
993.
The historical development of the concept of catatonia in affective disorders and contemporary papers on this topic are reviewed. In addition, data from a current study on the frequency of catatonia in mixed mania are reported. Differences between catatonic and noncatatonic patients with mixed mania are presented and their relevance to clinical practice is discussed.  相似文献   
994.
The objective of this study was to examine the association among the duration of COPD, degree of hypoxemia, and neurological abnormalities including cognitive functioning. Fifty-four patients with severe COPD and 24 age- and sex-matched controls, were included in the study. All patients and controls were administered pulmonary function tests, standardized Mini-mental State Examination (MMSE), Blessed Dementia Scale (BDS), Physical Self-maintenance Scale (PSMS), Modified Activities of Daily Living scale (MADL), Instrumental Activities of Daily Living scale (IADL), Cornell Scale for Depression in Dementia (CSDD), Global Deterioration Scale (GDS) and Clinical Dementia Rating (CDR). In addition, detailed physical and neurological examinations were performed. Sixty-four percent of patients with COPD showed abnormalities in MMSE, predominantly in recent memory, construction, attention, language, and orientation domains. Functional abnormalities were correlated with cognitive abnormalities. Although COPD patients did not show significant depression compared to controls, 77.7%. of the patients showed subjective and objective cognitive disturbance and 72.2% of the patients were classified as questionable or mild dementia. In conclusion, patients with COPD show significant cognitive and functional impairments that cannot be explained just by coincidence or by depression.  相似文献   
995.
In most studies on animal learning, individual animals are tested separately in a specific learning environment and with a limited number of trials per day. An alternative approach is to test animals in a familiar environment in their social group. In this study, the authors--applying a fully automated learning device--investigated voluntary, self-controlled visual shape discrimination learning of group-housed dwarf goats (Capra hircus). The majority of the tested goats showed successful shape discrimination, which indicates the adaptive value of an effective learning strategy. However, in each group, a few individual goats developed behavioral strategies different from shape discrimination to get reward. Relocation impairs memory retrieval (probably by attention shifting) only temporarily for previously learnt shapes. The results demonstrate the usefulness of a self-controlled learning paradigm to assess learning abilities of social species in their normal social settings. This may be especially relevant for captive animals to improve their welfare.  相似文献   
996.
997.
In this study, the authors explored whether wisdom-related performance could be enhanced by an instruction referring to the abstract concept of wisdom ("try to give a wise response"). The authors used three levels of activation of the concept of wisdom as well as intelligence-activation and control conditions in a heterogeneous sample of three age groups (N = 318). Results showed no general effect of the wisdom-concept instructions but did show an aptitude (resource) treatment interaction: Participants high in preparedness resources associated with wisdom exhibited some gains, whereas the performance of resource-low participants actually declined after the instruction. Implications and consequences with respect to ways of enhancing the expression of wisdom-related knowledge are discussed.  相似文献   
998.
The purpose of this study was to evaluate Denizli midwives’ self-reported knowledge of genetic diseases and genetic counseling. Data was collected on forms that obtained information about midwives approaches to basic genetics, genetic disorders, and genetic counseling (response rate = 70.1%). The highest response rate of midwives describing themselves as “knowledgeable” about basic genetic information was for mitosis and meiosis with 4.8%, about genetic disorders was for phenylketonuria with 61.1%, and about genetic counseling was for recommending ultrasonography during pregnancy with 98.1%. The source for basic genetics information for 56.4% of participants was in their school level classes. None of the midwives felt that they had sufficient knowledge about genetic counseling or screening and 76.4% would like to attend an educational course. Even though the midwives have recognized their knowledge deficit they occasionally give genetic counseling. As a result of this study a genetics course is planned for midwives so they can actively participate in the prevention and early diagnosis of genetic diseases.  相似文献   
999.
Impairment of hippocampal function precedes frontal and parietal cortex impairment in human Alzheimer's disease (AD). Neurotrophins are critical for behavioral performance and neuronal survival in AD. We used complex and radial mazes to assess spatial orientation and learning in wild-type and B6-Tg(ThylAPP)23Sdz (APP23) animals, a transgenic mouse model of AD. We also assessed brain content of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3). Performance was alike in wild-type and APP23 animals in the radial maze. In contrast, performance in the complex maze was better in wild-type than APP23 animals. Contrary to the wild-type, hippocampal BDNF levels decreased on training in APP23 animals. Hippocampal and frontal cortex NGF levels in APP23 animals correlated with the time to solve the complex maze, but correlated inversely with escape time in wild-type animals. NT-3 levels were alike in wild-type and APP23 animals and were unchanged even after training. Both types of mazes depend on hippocampal integrity to some extent. However, according to the cognitive mapping theory of spatial learning, the complex maze because of the increased complexity of the environment most likely depends more strongly on preserved hippocampal function than the radial maze in the working memory configuration applied here. Greater impairment in complex maze performance than in radial maze performance thus resembles the predominant affliction of the loss of hippocampal function in human AD. NGF and BDNF levels on maze learning are different in wild-type and transgenic animals, indicating that biological markers of AD may be altered on challenge even though equilibrium levels are alike.  相似文献   
1000.
Rüdell K  Myers L  Newman S 《Psychology, health & medicine》2006,11(2):171-81; quiz 781-9
Despite beneficial outcomes of patients' involvement in medical decision processes, it has been claimed that patients are generally not interested in medical decision making (MDM). Whereas current research focuses on actual MDM, this research explored the impact of nationality and perceptual processes of MDM. Preferences for involvement in decision making were examined in a sample of 204 German and 143 British university students. Hierarchical multiple regressions were employed to explore the link between socio-demographic information, individuals' perceived relationship with their GP, Health Locus of Control - Powerful Others, perceptions regarding the frequency and sufficiency of information provision and involvement in MDM, and individuals' preferred level of involvement and information. A significant amount of the variance in individuals preferences for involvement could be explained (Adjusted R2 = .59, p < .001). Independent t-test analyses showed that British and German perceptions of care differed significantly on a variety of different measures. Separate analyses for the German and British group highlighted cross-national differences in care and preferences for involvement. The study suggests that preferences to become involved might depend more on perceptual processes than actual involvement in decision making, and that communication and national health policy could play an important role.  相似文献   
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