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981.
Across three experiments, participants made speeded elevation discrimination responses to vibrotactile targets presented to the thumb (held in a lower position) or the index finger (upper position) of either hand, while simultaneously trying to ignore visual distractors presented independently from either the same or a different elevation. Performance on the vibrotactile elevation discrimination task was slower and less accurate when the visual distractor was incongruent with the elevation of the vibrotactile target (e.g., a lower light during the presentation of an upper vibrotactile target to the index finger) than when they were congruent, showing that people cannot completely ignore vision when selectively attending to vibrotactile information. We investigated the attentional, temporal, and spatial modulation of these cross-modal congruency effects by manipulating the direction of endogenous tactile spatial attention, the stimulus onset asynchrony between target and distractor, and the spatial separation between the vibrotactile target, any visual distractors, and the participant’s two hands within and across hemifields. Our results provide new insights into the spatiotemporal modulation of crossmodal congruency effects and highlight the utility of this paradigm for investigating the contributions of visual, tactile, and proprioceptive inputs to the multisensory representation of peripersonal space.  相似文献   
982.
定言命令作为人的意志的最高原则,首先预设人具有认识、情感以及欲求这三种能力;其次预设低级欲求能力和高级欲求能力的区分。从低级欲求能力出发,人按照以偏好为基础的准则行动,从高级欲求能力出发,定言命令对这些准则进行检验,要求这些准则具有普遍的立法形式。敬重感标志着高级欲求能力的存在,广义的道德感有识别道德情境和直接驱动性的作用。人追求自身的幸福和自由,希望不受他人的阻碍,在道德法则的范围内,做想做的任何事情。然而,特定的激情和情欲会导致人丧失自我,这种丧失是在实践上最大的恶。由此,作者论证:自我拥有是康德实践哲学中最核心的概念,尽管康德在其生前公开出版的著作中尚未明确地提到这个概念。  相似文献   
983.
Physical activity impacts functional recovery following stroke in humans, however its effects in experimental animals submitted to chronic cerebral hypoperfusion have not been investigated. The aim of this study was to evaluate the therapeutic potential of exercise, as assessed by cognitive activity in the Morris water maze and the brain oxidative status, through measurement of macromolecules damage, TBARS levels and total cellular thiols, as well as antioxidant enzymes in hippocampus, striatum and cerebral cortex. Adult male Wistar rats were submitted to the modified permanent bilateral occlusion of the common carotid arteries (2VO) method, with right common carotid artery being first occluded, and tested 3 months after the ischemic event. The effects of three different exercise protocols were examined: pre-ischemia, post-ischemia and pre+post-ischemia. Physical exercise consisted of sessions of 20-min, 3 times per week during 12 weeks (moderate intensity). Rats were submitted to cognitive assessment, in both reference and working spatial memory and after the last testing session were sacrificed to have oxidative stress parameters determined. Hypoperfusion caused a significant cognitive deficit in both spatial water maze tasks and this effect was reversed in rats receiving exercise protocol post and pre+post the ischemic event. Moreover, forced regular treadmill exercise regulated oxidative damage and antioxidant enzyme activity in the hippocampus. These results suggest that physical exercise protects against cognitive and biochemical impairments caused by chronic cerebral hypoperfusion.  相似文献   
984.
Several parameters related to the timing, grip force and load force involved in a precision grasping task were studied in patients with Parkinson's disease (PD) at different moments of medication and healthy controls, using a sensorized anthropomorphic device which was totally adapted to the human hand. The aim of this work was to carry out an accurate study of the reach-load-grip-hold-place-release subtasks to identify any physical motor impairment, its relation to medication and Parkinsonian strategies. Twenty seven patients in ON and OFF-like medication moments, and twenty seven age-matched controls took part in the experiment, which consisted of using the index finger and the thumb to perform a precision motor task involving different experimental objects. Visual cues were used as distracting elements. Results showed several motor parameters impaired in OFF-like medication moment but attenuated in ON state, suggesting a medication effect on the performance of the task.  相似文献   
985.
The present study examined the joint development of substance use and externalizing problems in early and middle adolescence. First, it was tested whether the relevant groups found in previous studies i.e., those with an early onset, a late onset, and no onset or low levels of risk behavior could be identified, while using a developmental model of a single, underlying construct of risk behavior. Second, departing from Moffitt's taxonomy of antisocial behavior, it was tested if early, but not late, onset risk behavior is predicted by a problematic risk profile in childhood. Data were used from TRAILS, a population based cohort study, starting at age 11 with two follow-ups at mean ages of 13.6 and 16.3 years. Latent transition analyses demonstrated that, both in early and middle adolescence, a single underlying construct of risk behavior, consisting of two classes (labeled as low and high risk behavior), adequately represented the data. Respondents could be clearly classified into four possible transition patterns from early to middle adolescence, with a transition from high to low being almost non-existent (2.5 %), low to low (39.4 %) and low to high (41.8 %) being the most prevalent, and high to high (16.2 %) substantial. As hypothesized, only the high-high group was characterized by a clear adverse predictor profile in late childhood, while the low-high group was not. This study demonstrates that the development of substance use is correlated with externalizing problems and underscores the theory that etiologies of early and later onset risk behavior are different.  相似文献   
986.
This study examined whether "melodic contour deafness" (insensitivity to the direction of pitch movement) in congenital amusia is associated with specific types of pitch patterns (discrete versus gliding pitches) or stimulus types (speech syllables versus complex tones). Thresholds for identification of pitch direction were obtained using discrete or gliding pitches in the syllable /ma/ or its complex tone analog, from nineteen amusics and nineteen controls, all healthy university students with Mandarin Chinese as their native language. Amusics, unlike controls, had more difficulty recognizing pitch direction in discrete than in gliding pitches, for both speech and non-speech stimuli. Also, amusic thresholds were not significantly affected by stimulus types (speech versus non-speech), whereas controls showed lower thresholds for tones than for speech. These findings help explain why amusics have greater difficulty with discrete musical pitch perception than with speech perception, in which continuously changing pitch movements are prevalent.  相似文献   
987.
The threat of being judged stereotypically (stereotype threat) may impair memory performance in older adults, thereby producing inflated age differences in memory tasks. However, the underlying mechanisms of stereotype threat in older adults or other stigmatized groups remain poorly understood. Here, we offer evidence that stereotype threat consumes working memory resources in older adults. More important, using a process-dissociation procedure, we found, for the first time, that stereotype threat undermines the controlled use of memory and simultaneously intensifies automatic response tendencies. These findings indicate that competing models of stereotype threat are actually compatible and offer further reasons for researchers and practitioners to pay special attention to age-related stereotypes during standardized neuropsychological testing.  相似文献   
988.
We challenge the classic experience/expression dichotomous account of emotions, according to which experiencing and expressing an emotion are two independent processes. By endorsing Dewey's and Mead's accounts of emotions, and capitalizing upon recent empirical findings, we propose that expression is part of the emotional experience. This proposal partly challenges the purely constructivist approach endorsed by the authors of the target article.  相似文献   
989.
Medically unexplained symptoms (MUS) are one of the key features of somatoform disorders. Although MUS are currently treated as both categorical (in terms of the diagnosis of somatoform disorders) and dimensional (in terms of quantitative measures of somatization/somatic symptom reporting), little is known about the empirical latent structure of MUS. Using taxometric analyses, the latent structure of somatic symptom reporting was analyzed with the Patient Health Questionnaire (PHQ)-15 in two student samples (N = 782 and N = 2,577) and a primary care sample (N = 519). We applied three popular taxometric methods: Maximum Eigenvalue (MAXEIG), Mean Above Minus Below a Cut (MAMBAC) and Latent-Mode (L-Mode). Simulation data were created to evaluate the appropriateness of the data for our analyses and to create the comparison curve fit index (CCFI) as an objective outcome measure. The results of all taxometric methods in any of the three data sets were in favor of a dimensional solution (CCFI < .50). Simulated taxonic and dimensional datasets differed substantially and the samples were appropriate for taxometric analysis. Accordingly, the latent structure of somatization/somatic symptom reporting as assessed by the PHQ-15 is dimensional in both primary care and student samples. Implications regarding the practical application as well as models of etiology and pathogenesis of somatic symptom reporting are discussed. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
990.
<正> 尽管长时记忆(LTM)形成要求蛋白质合成等一系列生化步骤方面的证据现在已甚为强烈,但是,一些其它的生理生化过程同样能调节记忆的形成。事实上已提出记忆形成包括若干阶段的图式、并有假设认为特定的记忆中务须考虑到的那些阶级,如Gibbs等人的实验假设(Gibbs与Ng,1977)。研究所得的证据支持上述记忆阶段存在。为记忆形成所必须的蛋白质合成假设激发起大量研究并出现了若干篇近代研究的综述(如Dunn,1980;Rosen—  相似文献   
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