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181.
Linguistic background has been identified as important in the perception of pitch, particularly between tonal versus nontonal languages. In addition, a link between native language and the perception of musical pitch has also been established. This pilot study examined the perception of pitch between listeners from tonal and nontonal linguistic cultures where two different styles of music originate. Listeners were 10 individuals born in China who ranged in age from 25 to 37 years and had spent on the average 30 mo. in the USA and 10 individuals, born on the Indian subcontinent, who ranged in age from 22 to 31 years, and had spent an average of 13 mo. in the USA. Listeners from both groups participated in two conditions. One condition involved listening to a selection of music characteristic of the individual's culture (China, pentatonic scale; Indian subcontinent, microtones), and one condition involved no music. All listeners within each condition participated in two voice pitch-matching tasks. One task involved matching the lowest and highest pitch of tape-recorded voices to a note on an electronic keyboard. Another task involved matching the voice pitch of tape-recorded orally read words to a note on the keyboard. There were no differences between the two linguistic groups. Methodological limitations preclude generalization but provide the basis for further research.  相似文献   
182.
Some patients with prosopagnosia may have an apperceptive basis to their recognition defect. Perceptual abnormalities have been reported in single cases or small series, but the causal link of such deficits to prosopagnosia is unclear. Our goal was to identify candidate perceptual processes that might contribute to prosopagnosia, by subjecting several prosopagnosic patients to a battery of functions that may be necessary for accurate facial perception. We tested seven prosopagnosic patients. Three had unilateral right occipitotemporal lesions, two had bilateral posterior occipitotemporal lesions, and one had right anterior-to-occipital temporal damage along with a small left temporal lesion. These lesions all included the fusiform face area, in contrast to one patient with bilateral anterior temporal lesions. Most patients had impaired performance on face-matching tests and difficulty with subcategory judgments for non-face objects. The most consistent deficits in patients with lesions involving the fusiform face area were impaired perception of spatial relations in dot patterns and reduced contrast sensitivity in the 4 to 8 cycles deg(-1) range. Patients with bilateral lesions were impaired in saturation discrimination. Luminance discrimination was normal in all but two patients, and spatial resolution was uniformly spared. Curvature and line-orientation discrimination were impaired in only one patient, who also had the most difficulty with more basic-level object recognition. We conclude that deficits in luminance, spatial resolution, curvature, line orientation, and contrast at low spatial frequencies are unlikely to contribute to apperceptive prosopagnosia. More relevant may be contrast sensitivity at higher spatial frequencies and the analysis of object spatial structure. Deficits in these functions may impair perception of subtle variations in object shape, and may be one mechanism by which the recognition defect in prosopagnosia can extend to other classes of object subcategorization.  相似文献   
183.
The nucleus accumbens (NAcc) has been shown to play a role in motor and spatial learning. Protein kinase C (PKC) has been implicated in the mechanisms of initiation and maintenance of long-term potentiation that is thought to be involved in the storage of long-term memory. In the present study, the importance of de novo synthesis of PKC-gamma within the NAcc in the acquisition and retention of spatial discrimination learning was assessed using an antisense knockdown approach. Separate groups of Long-Evans rats were exposed to acute microinfusions (6microg/microl) of PKC-gamma antisense oligodeoxynucleotide (AS-ODN), control oligodeoxynucleotide (C-ODN) or vehicle into the NAcc at 24 and 3h before each training session. Behavioral findings showed that the blockade of NAcc-PKC-gamma translation caused impairments in the early phase of learning and retention of spatial information. Biochemical experiments showed that PKC-gamma expression was reduced and Ca(2+)/phospholipid-dependent protein kinase C (PKC) activity was blocked significantly in the AS-ODN-treated rats in comparison with control rats. The present findings suggest that NAcc-PKC-gamma plays a role during the early acquisition of spatial learning. Also, retention test results suggest that NAcc-PKC-gamma may be working as an intermediate factor involved in the onset of molecular mechanisms necessary for spatial memory consolidation within the NAcc.  相似文献   
184.
Adult male Wistar rats with a substantia nigra pars compacta (SNc) lesion induced by intranigral administration of 1 micromol 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were used as a model of early phase Parkinson's disease (PD). This lesion caused a partial depletion of striatal dopamine (DA). The animals were submitted to a spatial working memory version of the water maze task in which they had to find a hidden (submersed) platform using online-maintained information that the platform remains in the same place during four consecutive trials, but that it is moved to another place every training day. Left, but not right SNc-lesioned rats were impaired in finding the platform in the second trial. This result suggests that the left SNc plays a key role in spatial working memory. Control experiments ruled out the possibility that motor impairment, sensory neglect, and/or impairment in the mental representation of the contralateral spatial environment had affected performance of the SNc-lesioned rats.  相似文献   
185.
The lexically based Five-Factor Personality Inventory (FFPI) was correlated with the factors and facets of the Revised NEO Personality Inventory (NEO-PI-R) in Belgian (N = 265), American (N = 116), and Hungarian (N = 320) samples. Results were similar across the three cultures. Analysis of orthogonalized FFPI factors showed that three of them--emotional stability, extraversion, and agreeableness--showed a direct correspondence to their NEO-PI-R counterparts. Autonomy, however, was not clearly related to openness, and facet analysis suggested that it might be interpreted as a dominance factor Better matches to NEO-PI-R conscientiousness and openness could be obtained by using vectors rotated 30 degrees from the FFPI positions. Raw scale scores showed similar results. Researchers should not assume that all measures of the Five-Factor Model are qualitatively similar  相似文献   
186.
187.
A latent-variable study examined whether verbal and visuospatial working memory (WM) capacity measures reflect a primarily domain-general construct by testing 236 participants in 3 span tests each of verbal WM. visuospatial WM, verbal short-term memory (STM), and visuospatial STM. as well as in tests of verbal and spatial reasoning and general fluid intelligence (Gf). Confirmatory' factor analyses and structural equation models indicated that the WM tasks largely reflected a domain-general factor, whereas STM tasks, based on the same stimuli as the WM tasks, were much more domain specific. The WM construct was a strong predictor of Gf and a weaker predictor of domain-specific reasoning, and the reverse was true for the STM construct. The findings support a domain-general view of WM capacity, in which executive-attention processes drive the broad predictive utility of WM span measures, and domain-specific storage and rehearsal processes relate more strongly to domain-specific aspects of complex cognition.  相似文献   
188.
Freyd and Tversky's [Am. J. Psychol. 97 (1984) 109] data suggested that human observers tend to overestimate relatively high levels of symmetry (symmetry effect), and tend to underestimate relatively low levels of symmetry (asymmetry effect). However, on the basis of their holographic approach to visual regularity, van der Helm and Leeuwenberg [Psychol. Rev. 103(3) (1996) 429] predicted that, at any level of symmetry, both symmetry and asymmetry effects may occur as a consequence of correct estimates of symmetry-to-noise ratios. This prediction was tested in two experiments, with tasks and stimuli similar to those in Freyd and Tversky's study. First, subjects had to judge whether a noisy symmetry is more similar to a slightly more symmetrical variant or to a slightly less symmetrical variant. Second, for every pair of stimuli in such a triadic comparison, subjects had to judge which stimulus is the more symmetrical one. The results from both experiments show that the occurrence of (a)symmetry effects indeed depends on symmetry-to-noise ratios.  相似文献   
189.
Finitary quasivarieties are characterized categorically by the existence of colimits and of an abstractly finite, regularly projective regular generator G. Analogously, infinitary quasivarieties are characterized: one drops the assumption that G be abstractly finite. For (finitary) varieties the characterization is similar: the regular generator is assumed to be exactly projective, i.e., hom(G, –) is an exact functor. These results sharpen the classical characterization theorems of Lawvere, Isbell and other authors.Supported by the Czech Grant Agency (Project 201/02/0148).Special issue of Studia Logica: Algebraic Theory of Quasivarieties Presented by M. E. Adams, K. V. Adaricheva, W. Dziobiak, and A. V. Kravchenko  相似文献   
190.
This study used midazolam-induced amnesia to explore the plausibility of the estimates provided by the process dissociation procedure (PDP), which is designed to estimate the contributions of recollection (R) and automatic (A) processes to implicit memory performance. In a double-blind, placebo-controlled, within-subject design with 24 participants, single midazolam doses were administered intravenously, and word stem completion performance was used to calculate PDP estimates. A dissociation was observed such that midazolam decreased R but increased A estimates relative to placebo. Given that a manipulation that induces amnesia would not be expected to facilitate a memory process, these results add to the accumulating body of evidence suggesting that PDP estimates are not always theoretically plausible. Such evidence raises important questions about the use of the PDP.  相似文献   
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