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871.
Category training can induce category effects, whereby color discrimination of stimuli spanning a newly learned category boundary is enhanced relative to equivalently spaced stimuli from within the newly learned category (e.g., categorical perception). However, the underlying mechanisms of these acquired category effects are not fully understood. In the current study, Event-Related Potentials (ERPs) were recorded during a visual oddball task where standard and deviant colored stimuli from the same or different novel categories were presented. ERPs were recorded for a test group who were trained on these novel categories, and for an untrained control group. Category effects were only found for the test group on the trained region of color space, and only occurred during post-perceptual stages of processing. These findings provide new evidence for the involvement of cognitive mechanisms in acquired category effects and suggest that category effects of this kind can exist independent of early perceptual processes.  相似文献   
872.
Lothian Birth Cohorts, 1936 and 1921 were used to study the longitudinal comparability of Five-Factor Model (McCrae & John, 1992) personality traits from ages 69 to 72 years and from ages 81 to 87 years, and cross-cohort comparability between ages 69 and 81 years. Personality was measured using the 50-item International Personality Item Pool (Goldberg, 1999). Satisfactory measurement invariance was established across time and cohorts. High rank-order stability was observed in both cohorts. Almost no mean-level change was observed in the younger cohort, whereas Extraversion, Agreeableness, Conscientiousness, and Intellect declined significantly in the older cohort. The older cohort scored higher on Agreeableness and Conscientiousness. In these cohorts, individual differences in personality traits continued to be stable even in very old age, mean-level changes accelerated.  相似文献   
873.
The Fear of Positive Evaluation Scale (FPES; J. W. Weeks, R. G. Heimberg, & T. L. Rodebaugh, 2008) was designed to assess fear of positive evaluation, a proposed cognitive component of social anxiety. Although previous findings on the psychometric properties of the FPES have been highly encouraging, only 1 previous study has examined the psychometric profile of the FPES in a sample of patients with social anxiety disorder (T. A. Fergus et al., 2009). The primary purpose of the present study was to conduct a large multisite examination of the psychometric profile of the FPES among patients with a principal diagnosis of social anxiety disorder (n = 226; generalized subtype = 97.8%). Responses of nonanxious control participants (n = 42) were also examined. The factorial validity, internal consistency, test-retest reliability, construct validity, and treatment sensitivity of the FPES were strongly supported by our findings. Furthermore, an FPES cutoff score was identified for distinguishing levels of fear of positive evaluation characteristic of patients with social anxiety disorder from those characteristic of the control group. Results provide additional support for the psychometric properties of the FPES in clinical samples.  相似文献   
874.
mRNA translation, or protein synthesis, is a major component of the transformation of the genetic code into any cellular activity. This complicated, multistep process is divided into three phases: initiation, elongation, and termination. Initiation is the step at which the ribosome is recruited to the mRNA, and is regarded as the major rate-limiting step in translation, while elongation consists of the elongation of the polypeptide chain; both steps are frequent targets for regulation, which is defined as a change in the rate of translation of an mRNA per unit time. In the normal brain, control of translation is a key mechanism for regulation of memory and synaptic plasticity consolidation, i.e., the off-line processing of acquired information. These regulation processes may differ between different brain structures or neuronal populations. Moreover, dysregulation of translation leads to pathological brain function such as memory impairment. Both normal and abnormal function of the translation machinery is believed to lead to translational up-regulation or down-regulation of a subset of mRNAs. However, the identification of these newly synthesized proteins and determination of the rates of protein synthesis or degradation taking place in different neuronal types and compartments at different time points in the brain demand new proteomic methods and system biology approaches. Here, we discuss in detail the relationship between translation regulation and memory or synaptic plasticity consolidation while focusing on a model of cortical-dependent taste learning task and hippocampal-dependent plasticity. In addition, we describe a novel systems biology perspective to better describe consolidation.  相似文献   
875.
876.
Depressed individuals who ruminate have difficulties learning from punishment and suppressing task-irrelevant information. The C957T polymorphism of the DRD2 gene, which affects functioning of D2 dopamine receptors (DRD2) that are expressed predominantly in the indirect pathway of the basal ganglia, has been found to influence suppression and punishment learning. Given these associations, we examined in the present study whether depressive rumination is related to the C957T polymorphism in 317 clinically depressed individuals and 317 never-depressed control individuals. A 2 × 2 (diagnostic group ×C957T polymorphism) analysis of variance conducted on depressive rumination scores yielded a significant interaction of group and C957T: Individuals with two 957C alleles reported higher levels of depressive rumination than did individuals with one or two 957T alleles if they were depressed, but not if they were healthy. The present findings suggest that the dopaminergic system and DRD2 are related to the frequency of maladaptive rumination in depressed individuals. Thus, DRD2 may be an important target for the pharmacological treatment of depressive rumination.  相似文献   
877.
Accumulating evidence supports the premise that fear of evaluation in general is important in social anxiety, including fear of positive evaluation (FPE) as well as fear of negative evaluation (FNE). This study tested various hypotheses pertaining to a novel, expanded conceptualization of social anxiety involving these two distinct fears: the bivalent fear of evaluation (BFOE) model. Responses from a large undergraduate sample (N = 585) were examined. In addition, responses from a subsample of participants qualifying for a probable diagnosis of social anxiety disorder (SAD; n = 133) were examined, via mediational analyses, for potential mechanisms underlying FPE within highly socially anxious individuals. FPE exhibited a unique and significantly stronger relationship with concerns of social reprisal due to making positive impressions than did FNE. FPE related uniquely and negatively to trait positive affect/automatic thoughts, whereas FNE, FPE, and social anxiety all related uniquely and positively to trait negative affect/automatic thoughts. FPE, FNE, and social anxiety all related uniquely and positively to disqualification of positive social outcomes (DPSO). However, FPE related most strongly to DPSO attributions at the level of the self, and these attributions mediated the relationship between FPE and negative automatic thoughts in an analog clinical sample. Concerns of social reprisal due to making positive impressions on others mediated the relationship between FPE and DPSO attributions to others in an analog clinical sample. The obtained findings replicate and extend support for the BFOE model of social anxiety. Implications for the theoretical conceptualization and treatment of SAD are discussed.  相似文献   
878.
879.
Math relies on mastery and integration of a wide range of simpler numerical processes and concepts. Recent work has identified several numerical competencies that predict variation in math ability. We examined the unique relations between eight basic numerical skills and early arithmetic ability in a large sample (= 1391) of children across grades 1–6. In grades 1–2, children's ability to judge the relative magnitude of numerical symbols was most predictive of early arithmetic skills. The unique contribution of children's ability to assess ordinality in numerical symbols steadily increased across grades, overtaking all other predictors by grade 6. We found no evidence that children's ability to judge the relative magnitude of approximate, nonsymbolic numbers was uniquely predictive of arithmetic ability at any grade. Overall, symbolic number processing was more predictive of arithmetic ability than nonsymbolic number processing, though the relative importance of symbolic number ability appears to shift from cardinal to ordinal processing.  相似文献   
880.
The Knowledge Argument of Frank Jackson has not persuaded physicalists, but their replies have not dispelled the intuition that someone raised in a black and white environment gains genuinely new knowledge when she sees colors for the first time. In what follows, we propose an explanation of this particular kind of knowledge gain that displays it as genuinely new, but orthogonal to both physicalism and phenomenology. We argue that Mary’s case is an instance of a common phenomenon in which something new is learned as the result of exploiting representational resources that were not previously exploited, and that this results in gaining genuinely new information.  相似文献   
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