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211.
We introduce a Paraconsistent Informational Logic that formalizes the idea of conjectures which are acceptable as to the quality and the variety of the information that they convey with respect to a given theory T, even if they are classically inconsistent with T. The work constitutes an extension of a previously developed Informational Logic for classical frameworks, where a new notion of logical entropy measure H on formulas and on proofs plays a central role.  相似文献   
212.
The present fMRI study of semantic fluency for animal and tool names provides further evidence for category-specific brain activations, and reports task-related changes in effective connectivity among defined cerebral regions. Two partially segregated systems of functional integration were highlighted: the tool condition was associated with an enhancement of connectivity within left hemispheric regions, including the inferior prefrontal and premotor cortex, the inferior parietal lobule and the temporo-occipital junction; the animal condition was associated with greater coupling among left visual associative regions. These category-specific functional differences extend the evidence for anatomical specialization to lexical search tasks, and provide for the first time evidence of category-specific patterns of functional integration in word-retrieval.  相似文献   
213.
214.
Modified motion detectors can be used to monitor locomotor activity and measure endogenous rhythms. Although these devices can help monitor insects in their home cages, the small size of the animals requires a very short wavelength detector. We modified a commercial microwave-based detection device, connected the detector’s output to the digital input of a computer, and validated the device by recording circadian and ultradian rhythms.Periplaneta americana were housed in individual cages, and their activity was monitored at 18°C and subsequently at 28°C in constant darkness. Time series were analyzed by a discrete Fourier transform and a chi-square periodogram. Q10 values and the circadian free-running period confirmed the data reported in the literature, validating the apparatus. Moreover, the spectral analysis and periodogram revealed the presence of ultradian rhythmicity in the range of 1–8 h.  相似文献   
215.
The aim of this study was to compare the prevalence of Personality Disorders assessed by Structured Clinical Interview for Axis-II in 155 inpatients diagnosed with Unipolar Disorder vs inpatients with Bipolar Disorder (39). The most frequent Axis II diagnoses among Unipolar inpatients were Borderline (31.6%), Dependent (25.2%), and Obsessive-Compulsive (14.2%) Personality Disorders. Among Bipolar inpatients, the most prevalent personality disorders were Borderline (41%), Narcissistic (20.5%), Dependent (12.8%), and Histrionic disorders (10.3%). Using chi squared analysis, few differences in distribution emerged between the two groups: Unipolar patients had more recurrent Obsessive-Compulsive Personality Disorder than Bipolar patients (chi(1)2=6.24, p<.005). Comorbid Narcissistic Personality Disorder was significantly more frequent in the Bipolar than in the Unipolar group (chi(1)2=6.34, P<.01). Considering the three clusters (DSM-IV classification), there was a significant difference between the groups, Cluster C (fearful, avoidant) diagnoses being more frequent in the Unipolar than in the Bipolar group (48.4% vs 20.5%, respectively). Cluster B (dramatic, emotionally erratic) diagnoses were found more frequently in patients with Bipolar Disorders (71.8% vs 45.2% in Unipolar patients, chi(2)2=10.1, p<.006). The differences in the distribution and prevalence of Personality Disorders between the two patient groups are discussed.  相似文献   
216.
Action verbal fluency normative data for the elderly   总被引:2,自引:0,他引:2  
An emerging body of literature points to the prominent role of the frontal lobes in the retrieval of verbs, whereas production of common and proper nouns arguably is mediated primarily by posterior and anterior temporal regions, respectively. Although the majority of studies examining the neuroanatomic distinctions between verb and noun retrieval have relied on action naming tasks (naming depicted activities, e.g., running) as indicators of verb retrieval abilities, recent studies have utilized an action (verb) verbal fluency measure, the Action Fluency Test (AFT), to assess verb retrieval. Findings from these studies suggest that action fluency is sensitive to the integrity of fronto-subcortical neural circuitry and that it is a valid measure of executive and language functions. The AFT is an easily administered executive function measure, but no normative data for the AFT or other action fluency tasks has been published. This study was undertaken to provide initial AFT normative data for a sample of 145 healthy elderly subjects. As education is significantly correlated with AFT scores, the normative data are stratified by educational level.  相似文献   
217.
Eighty blindfolded healthy female subjects participated in an active and a passive straight-ahead pointing task to study the estimation of the subjective sagittal middle in the presence or absence of an active haptic exploration. Subjects were to point straight-ahead with their left or right index finger starting from different right- or left-sided locations, while performing either an active movement or with the hand being passively moved by the examiner. Results showed: (i) a significant effect of the hand used only on the active straight-ahead pointing task performance; (ii) a significant effect of the starting position both on the active and passive pointing performance; (iii) a significant correlation between the two protocols only in terms of spatial bias (algebraic error) but not in terms of precision (absolute errors). These results are discussed with regards to normal and neuropsychological studies of the egocentric frame of reference.  相似文献   
218.
Data from a sample of 500 undergraduate students showed that depression scores were more strongly correlated with suicide risk than were mania scores, uggesting that such traits should be routinely screened to evaluate suicide risk.  相似文献   
219.
The aims of this paper are (a) to gather support for the hypothesis that some basic mechanisms of attentional deployment (i.e., its high efficiency in dealing with expected and unexpected inputs) meet the requirements of the inferential system and have possibly evolved to support its functioning, and (b) to show that these orienting mechanisms function in very similar ways in two perceptual tasks and in a symbolic task. The general hypothesis and its predictions are sketched in the Introduction, after a discussion of current findings concerning visual attention and the generalities of the inferential system. In the empirical section, three experiments are presented where participants tracked visual trajectories (Experiments 1 and 3) or arithmetic series (Experiments 2 and 3), responding to the onset of a target event (e.g., to a specific number) and to the repetition of an event (e.g., to a number appearing twice consecutively). Target events could be anticipated when they were embedded in regular series/trajectories; they could be anticipated, with the anticipation later disconfirmed, when a regular series/trajectory was abruptly interrupted before the target event occurred; and they could not be anticipated when the series/trajectory was random. Repeated events could not be anticipated. Results show a very similar pattern of allocation in tracking visual trajectories and arithmetic series: Attention is focused on anticipated events; it is defocused and redistributed when an anticipation is not confirmed by ensuing events; however, performance decreases when dealing with random series/trajectory—that is, in the absence of anticipations. In our view, this is due to the fact that confirmed and disconfirmed anticipations are crucial events for “knowledge revision”—that is, the fine tuning of the inferential system to the environment; attentional mechanisms have developed so as to enhance detection of these events, possibly at all levels of inferential processing.  相似文献   
220.
According to 2-component theories of intelligence, negative cross-sectional age gradients in mechanic (broad Gf) and pragmatic (broad Gc) cognitive components reflect the increasing constraining of the former in the expression and integrity of the latter component. The authors examined this widely held but untested assumption by applying a recently proposed dynamic structural modeling technique, the bivariate dual change score model, to longitudinal data from the Berlin Aging Study (N = 516, age range = 70-103 years). Mechanics and pragmatics were indexed by perceptual speed and knowledge, respectively. As hypothesized, results indicated that changes in knowledge are dominated by perceptual speed and offered strong support for the notion of "mechanization" of pragmatic abilities in old and very old age.  相似文献   
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