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191.
192.
In this study we investigated the correlation between individual linguistic ability based on performance levels and their engagement of typical and atypical language areas in the brain. Eighteen healthy subjects between 21 and 64 years participated in language ability tests, and subsequent functional MRI scans measuring brain activity in response to a sentence completion and a word fluency task. Performance in both reading and high-level language tests correlated positively with increased right-hemispheric activation in the inferior frontal gyrus (specifically Brodmann area 47), the dorsolateral prefrontal cortex (DLPFC), and the medial temporal gyrus (Brodmann area 21). In contrast, we found a negative correlation between performance and left-hemispheric DLPFC activation.Our findings indicate that the right lateral frontal and right temporal regions positively modulate aspects of language ability.  相似文献   
193.
Growing experimental evidence suggests that temporal events are represented on a mental time line, spatially oriented from left to right. Support for the spatial representation of time comes mostly from studies that have used spatially organized responses. Moreover, many of these studies did not avoid possible confounds attributable to target stimuli that simultaneously convey both spatial and temporal dimensions. Here we show that task-irrelevant, lateralized visuospatial primes affect auditory duration judgments. Responses to short durations were faster when the auditory target was paired with left- than with right-sided primes, whereas responses to long durations were faster when paired with right- than with left-sided primes. Thus, when the representations of physical space and time are concurrently activated, physical space may influence time even when a lateralized, spatially encoded response is not required by the task. The time-space interaction reported here cannot be ascribed to any Spatial-Temporal Association of Response Codes effect. It supports the hypothesis that the representation of time is spatially organized, with short durations represented on the left space and longer ones on the right.  相似文献   
194.
In three experiments rats were given serial preexposure to two flavor stimuli. In Experiment 1, some animals were given exposure to AX followed by the presentation of BX, a forward schedule; the others were given backward preexposure (BX→AX). Conditioning and test trials with the A element showed that salience or effectiveness of A was better protected in the forward than in the backward condition. Experiments 2 and 3 assessed the relevance of this salience modulation mechanism for perceptual learning. In these experiments, generalization of a conditioned aversion from AX to BX was reduced in the forward (but not in the backward) condition only after prolonged exposure, indicating that the establishment of an inhibitory link from B to A is required for successful discrimination. However, generalization to a novel compound stimulus, NX, was reduced in the forward group both after short and long preexposure, suggesting the existence of salience modulation processes that work in parallel with associative inhibition. These results seem to support the existence of a salience modulation mechanism that seems to be beyond the scope of current theories of perceptual learning.  相似文献   
195.
This study aimed to evaluate the type of attentional selection (location- and/or object-based) triggered by two different types of central noninformative cues: eye gaze and arrows. Two rectangular objects were presented in the visual field, and subjects' attention was directed to the end of a rectangle via the observation of noninformative directional arrows or eye gaze. Similar experiments with peripheral cues have shown an object-based effect: faster target identification when the target is presented on the cued object as compared to the uncued object, even when the distance between target and cue was the same. The three reported experiments aimed to compare the location- and object-based attentional orienting observed with arrows and eye gaze, in order to dissociate the orienting mechanisms underlying the two types of orienting cues. Results showed similar cueing effects on the cued versus oppositely cued locations for the two cue types, replicating several studies with nonpredictive gaze and arrow cues. However, a pure object-based effect occurred only when an arrow cue was presented, whereas a pure location-based effect was only found for eye-gaze cues. It is suggested that attention is nonspecifically directed to nearby objects when a noninformative arrow is used as cue, whereas it is selectively directed to a specific cued location when noninformative eye gaze is used. This may be mediated by theory of mind mechanisms.  相似文献   
196.
Inhibition of return (IOR) is modulated by task set and appears later in discrimination tasks than in detection tasks. Several hypotheses have been suggested to account for this difference. We tested three of these hypotheses in two experiments by examining the influence of cue and target level of processing on the onset of IOR. In the first experiment, participants were required to respond to both the cue and target. The pattern of results showed that deeper processing of the cue or target advanced the onset of IOR. In the second experiment, participants were not required to respond to the cue and a reverse pattern of results emerged, which replicated the general findings in cuing tasks. We conclude that in more-demanding tasks, an additional process slows down the processing of a nonpredictive cue in order to enhance the processing of the target.  相似文献   
197.
Studies on determinants affecting child development are still limited in Greece. The aim of the present study was to describe the socio-demographic characteristics associated with neurodevelopment in infants aged 18 months in the Mother-Child Cohort (Rhea Study) in Crete, Greece. A total of 599 (72.9%) mothers agreed to participate in the neurodevelopment protocol and 612 infants (586 singletons and 26 twins) were assessed by means of the Bayley Scales of Infant and Toddler Development (3rd edition). The present analysis includes 605 infants. Multivariable linear regression models were implemented to examine the associations between the Bayley-III standardised scores and different parental and infant characteristics, also adjusting for quality of assessment. Girls were found to have better neurodevelopmental outcomes in cognitive, receptive and expressive communication, fine motor and social-emotional development. Maternal higher education was positively associated to almost all aspects of infant neurodevelopment assessed. Increasing number of older siblings was negatively associated with cognitive development, communication skills and gross motor development. Our results, also, suggest a positive effect of maternal employment on infants' receptive and expressive communication, and gross motor scores. The results of the present study suggest that in the population on Crete social and environmental factors contributed more to infants' neurodevelopment at 18 months than biological factors.  相似文献   
198.
The Career Adapt-Abilities Scale—Brazilian Form (CAASBrazil) consists of four scales which measure concern, control, curiosity, and confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas. Internal consistency estimates for the subscale and total scores ranged from good to excellent. The factor structure was quite similar to the one computed for combined data from 13 countries. CAASBrazil is similar to the International Form, with the exception of two items that were not included in Brazilian version. Concurrent validity evidence was collected relative to personality factors from the Five-Factor Model of Personality. The relationships between career adaptability and personality factors were as predicted.  相似文献   
199.
Background. Many contributing factors, both domain specific and domain general, influence children's performance in school achievement. Aims. This research aims to verify the importance of kindergarten measures of cognitive abilities and numerical competence in the role of predicting mathematical school achievement at the end of first grade. Sample and Methods. A total of 70 children (38 females and 32 males) took part in the study. We tested the children at the beginning of their last year of kindergarten (time 1) on the following cognitive abilities: IQ, phonology, counting skills, verbal short‐term memory, visuo‐spatial short‐term memory, working memory, and processing speed. Then, we tested the same children at end of their last year of kindergarten (time 2) on a measure of numerical competence and at the end of their first year of primary school (time 3) on a test of math achievement. Results. Path analysis models revealed the direct influence of working memory and processing speed on predicting numerical competence in pre‐schoolers and the influence of processing speed and verbal IQ on predicting math achievement in first graders. Moreover, this study found a direct link between numerical competence and math achievement. Conclusions. Both domain‐specific and domain‐general factors contribute to determining math achievement at the end of first grade.  相似文献   
200.
Background. Longitudinal studies allow us to identify, which specific maths skills are weak in young children, and whether there is a continuing weakness in these areas throughout their school years. Aims. This 2‐year study investigated whether certain socio‐demographic variables affect early mathematical competency in children aged 5–7 years. Sample. A randomly selected sample of 127 students (64 female; 63 male) participated. At the start of the study, the students were approximately 5 years old (M= 5.2; SD= 0.28; range = 4.5–5.8). Method . The students were assessed using the Early Numeracy Test and then allocated to a high (n= 26), middle (n= 76), or low (n= 25) achievers group. The same children were assessed again with the Early Numeracy Test at 6 and 7 years old, respectively. Eight socio‐demographic characteristics were also evaluated: family model, education of the parent(s), job of the parent(s), number of family members, birth order, number of computers at home, frequency of teacher visits, and hours watching television. Results . Early Numeracy Test scores were more consistent for the high‐achievers group than for the low‐achievers group. Approximately 5.5% of low achievers obtained low scores throughout the study. A link between specific socio‐demographic characteristics and early achievement in mathematics was only found for number of computers at home. Conclusions . The level of mathematical ability among students aged 5–7 years remains relatively stable regardless of the initial level of achievement. However, early screening for mathematics learning disabilities could be useful in helping low‐achieving students overcome learning obstacles.  相似文献   
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