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1.
Understanding how people think and how people organise knowledge are always major concerns for educational researchers. Hence, educators have developed various ways of representing learners' ‘cognitive structures‘. This article provides a review of the use of five methods of representing cognitive structures - free word association, controlled word association, tree construction, concept map and flow map. Through comparing the types of analyses that are generated from these cognitive structure representation methods, this paper discusses the applications, as well as the limitations, among these methods.  相似文献   

2.
As part of the Mobile Radiofrequency Phone Exposed Users' Study (MoRPhEUS), a cross‐sectional epidemiological study examined cognitive function in secondary school students. We recruited 317, 7th grade students (144 boys, 173 girls, median age 13 years) from 20 schools around Melbourne, Australia. Participants completed an exposure questionnaire based on the Interphone study, a computerised cognitive test battery, and the Stroop colour‐word test. The principal exposure metric was the total number of reported mobile phone voice calls per week. Linear regression models were fitted to cognitive test response times and accuracies. Age, gender, ethnicity, socio‐economic status and handedness were fitted as covariates and standard errors were adjusted for clustering by school. The accuracy of working memory was poorer, reaction time for a simple learning task shorter, associative learning response time shorter and accuracy poorer in children reporting more mobile phone voice calls. There were no significant relationships between exposure and signal detection, movement monitoring or estimation. The completion time for Stroop word naming tasks was longer for those reporting more mobile phone voice calls. The findings were similar for total short message service (SMS, also known as text) messages per week, suggesting these cognitive changes were unlikely due to radiofrequency (RF) exposure. Overall, mobile phone use was associated with faster and less accurate responding to higher level cognitive tasks. These behaviours may have been learned through frequent use of a mobile phone. Bioelectromagnetics 30:678–686, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

3.
李雅轩  张飞雄  胡英考  蔡民华  赵昕 《遗传》2010,32(8):864-868
概念图是表征和揭示知识结构中意义联系的图表。在遗传学教学中, 选择性地使用概念图有助于教师进行课程内容的组织与复习, 检测学生的学习成果; 概念图的应用可以提升学生的认知水平, 帮助学生建立系统完整的知识体系。文章对概念图在遗传学教学中的探索与应用进行了概述。  相似文献   

4.
Reading disability exhibited defects in different cognitive domains, including word reading fluency, word reading accuracy, phonological awareness, rapid automatized naming and morphological awareness. To identify the genetic basis of Chinese reading disability, we conducted a genome-wide association study (GWAS) of the cognitive traits related to Chinese reading disability in 2284 unrelated Chinese children. Among the traits analyzed in the present GWAS, we detected one genome-wide significant association (p < 5 × 10−8) on word reading fluency for one SNP on 4p16.2, within EVC genes (rs6446395, p = 7.33 × 10−10). Rs6446395 also showed significant association with Chinese character reading accuracy (p = 2.95 × 10−4), phonological awareness (p = 7.11 × 10−3) and rapid automatized naming (p = 4.71 × 10−3), implying multiple effects of this variant. The eQTL data showed that rs6446395 affected EVC expression in the cerebellum. Gene-based analyses identified a gene (PRDM10) to be associated with word reading fluency at the genome-wide level. Our study discovered a new candidate susceptibility variant for reading ability and provided new insights into the genetics of developmental dyslexia in Chinese children.  相似文献   

5.
Variation in cognitive performance, which strongly predicts functional outcome in schizophrenia (SZ), has been associated with multiple immune‐relevant genetic loci. These loci include complement component 4 (C4A), structural variation at which was recently associated with SZ risk and synaptic pruning during neurodevelopment and cognitive function. Here, we test whether this genetic association with cognition and SZ risk is specific to C4A, or extends more broadly to genes related to the complement system. Using a gene‐set with an identified role in “complement” function (excluding C4A), we used MAGMA to test if this gene‐set was enriched for genes associated with human intelligence and SZ risk, using genome‐wide association summary statistics (IQ; N = 269 867, SZ; N = 105 318). We followed up this gene‐set analysis with a complement gene‐set polygenic score (PGS) regression analysis in an independent data set of patients with psychotic disorders and healthy participants with cognitive and genomic data (N = 1000). Enrichment analysis suggested that genes within the complement pathway were significantly enriched for genes associated with IQ, but not SZ. In a gene‐based analysis of 90 genes, SERPING1 was the most enriched gene for the phenotype of IQ. In a PGS regression analysis, we found that a complement pathway PGS associated with IQ genome‐wide association studies statistics also predicted variation in IQ in our independent sample. This association (observed across both patients and controls) remained significant after controlling for the relationship between C4A and cognition. These results suggest a robust association between the complement system and cognitive function, extending beyond structural variation at C4A.  相似文献   

6.
Postural control in quiet stance although simple still requires some cognitive resources; dual cognitive tasks influence further postural control. The present study examines whether or not dyslexic teenagers experience postural instability when performing a Stroop dual task for which their performances are known to be poor. Fifteen dyslexics and twelve non-dyslexics (14 to 17 years old) were recruited from the same school. They were asked to perform three tasks: (1) fixate a target, (2) perform an interference Stroop test (naming the colour or the word rather than reading the word), (3) performing flexibility Stroop task: the subject performed the interference task as in (2) except when the word was in a box, in which case he had to read the word. Postural performances were measured with a force platform. The results showed a main task effect on the variance of speed of body sway only: such variance was higher in the flexibility task than for the other two tasks. No group effect was found for any of the parameters of posture (surface, mediolateral and anteroposterior sway, variance of speed). Further wavelet analysis in the time-frequency domain revealed an increase in the spectral power of the medium frequency range believed to be related to cerebellum control; an accompanying increase in the cancellation time of the high frequency band related to reflexive loops occurred for non-dyslexics only. These effects occurred for the flexibility task and could be due to its high cognitive difficulty. Dyslexics displayed shorter cancellation time for the medium frequency band for all tasks, suggesting less efficient cerebellar control, perhaps of eye fixation and attention influencing body sway. We conclude that there is no evidence for a primary posture deficit in 15 year old teenagers who come from the general population and who were recruited in schools.  相似文献   

7.
In this study female students in different phases of the menstrual cycle made a test of word association. The results were represented and compared in a pathfinder-network. This special network is a model of knowledge representation in which words are portrayed as nodes, and links between nodes represent associations. This method (pathfinder), developed by Schvaneveldt (1990), generates associative networks from individual's ratings of similarity of word pairs. 51 women had to judge 45 words of the three categories sexual, romantic and neutral in similarity. These networks were compared regarding probability of contraception, partnership and level of testosterone. The number and weights of links differed between women with high and low probability of contraception. The level of testosterone had a large influence on the density of associations, especially in sexual contents.  相似文献   

8.
The cognitive analysis of adult language disorders continues to draw heavily on linguistic theory, but increasingly it reflects the influence of connectionist, spreading activation models of cognition. In the area of spoken word production, ‘localist’ connectionist models represent a natural evolution from the psycholingistic theories of earlier decades. By contrast, the parallel distributed processing framework forces more radical rethinking of aphasic impairments. This paper exemplifies these multiple influences in contemporary cognitive aphasiology. Topics include (i) what aphasia reveals about semantic-phonological interaction in lexical access; (ii) controversies surrounding the interpretation of semantic errors and (iii) a computational account of the relationship between naming and word repetition in aphasia. Several of these topics have been addressed using case series methods, including computational simulation of the individual, quantitative error patterns of diverse groups of patients and analysis of brain lesions that correlate with error rates and patterns. Efforts to map the lesion correlates of nonword errors in naming and repetition highlight the involvement of sensorimotor areas in the brain and suggest the need to better integrate models of word production with models of speech and action.  相似文献   

9.
Khrennikov AY 《Bio Systems》2007,90(3):656-675
We try to perform geometrization of cognitive science and psychology by representing information states of cognitive systems by points of mental space given by a hierarchic m-adic tree. Associations are represented by balls and ideas by collections of balls. We consider dynamics of ideas based on lifting of dynamics of mental points. We apply our dynamical model for modeling of flows of unconscious and conscious information in the human brain. In a series of models, Models 1–3, we consider cognitive systems with increasing complexity of psychological behavior determined by structure of flows of associations and ideas.  相似文献   

10.
The level of population structure and the extent of linkage disequilibrium (LD) can have large impacts on the power, resolution, and design of genome-wide association studies (GWAS) in plants. Until recently, the topics of LD and population structure have not been explored in oat due to the lack of a high-throughput, high-density marker system. The objectives of this research were to survey the level of population structure and the extent of LD in oat germplasm and determine their implications for GWAS. In total, 1,205 lines and 402 diversity array technology (DArT) markers were used to explore population structure. Principal component analysis and model-based cluster analysis of these data indicated that, for the lines used in this study, relatively weak population structure exists. To explore LD decay, map distances of 2,225 linked DArT marker pairs were compared with LD (estimated as r 2). Results showed that LD between linked markers decayed rapidly to r 2 = 0.2 for marker pairs with a map distance of 1.0 centi-Morgan (cM). For GWAS, we suggest a minimum of one marker every cM, but higher densities of markers should increase marker-QTL association and therefore detection power. Additionally, it was found that LD was relatively consistent across the majority of germplasm clusters. These findings suggest that GWAS in oat can include germplasm with diverse origins and backgrounds. The results from this research demonstrate the feasibility of GWAS and related analyses in oat.  相似文献   

11.
This paper is concerned with a branch of computational biology related to protein prediction and analysis of secondary structure of proteins. Although traditional methods use a simple amino acid composition to predict the secondary structure content, hydrophobicity has been recently found to improve the results in this and several related prediction tasks. To this end, we propose and analyze advantages of two new hydrophobicity index-based scales that incorporate information about long-range interactions along the protein sequence and contrast them with currently used raw hydrophobic index values. We also compare three leading hydrophobicity indices, i.e., Eisenberg's, Fauchere-Pliska's, and Cid's, using the proposed scales. The analysis is performed using fuzzy cognitive maps that quantify the strength of relation between the hydrophobicity scales/indices and the protein content values. A set of empirical tests that involve generation of fuzzy cognitive map models for a set of 200 low homology proteins have been performed. The results show that the secondary structure content along the protein sequence is characterized by about 2.5 times stronger relation with the two proposed hydrophobicity scales when compared with the currently used raw index values. The new scales exhibit stronger relation irrespective of the applied hydrobhobicity indices. Analysis of different scales shows superiority of the Eisenberg's hydrophobicity index, when used with the new scales. In contrast, the Fauchere-Pliska's index is found to perform better when compared with the two other indices when using raw hydrophobic index values that disregard the long-range interactions.  相似文献   

12.

Background

Research has shown that students have a variety of ideas about natural selection that may be context dependent. Prior analyses of student responses to open-ended evolution items have demonstrated that students apply more core ideas about natural selection when asked about animals, but respond with the same number of naive ideas for plant and animal items. Other research has shown that changing an item to ask about trait loss or gain shifted the types of naive ideas applied by students in their responses. In this paper, we take up both of these findings to determine if differences exist in the types of ideas students apply to similar items with either a plant or an animal in the item stem.

Results

In order to understand if students applied different ideas to plants or animals in distractor-driven multiple-choice questions, we analyzed high school biology students’ responses to matched-item pairs. Dichotomous scoring revealed that students chose the correct response more often for the animal items as compared to the plant items. Chi squared analyses revealed significant differences in the distribution of student responses to matched items. For example, more students chose responses that defined animal fitness as related to their strength and plants’ fitness related to its longevity.

Conclusions

These results suggest that varied context of plants or animals in item stems on diagnostic assessments can provide teachers with a more complete picture of their students’ ideas about natural selection prior to instruction. This is particularly important in assessments used prior to instruction; as teachers will gain greater insight into the variety of ways students think about natural selection across different types of plants and animals.
  相似文献   

13.
To avoid problems related to unknown population substructure, association studies may be conducted in founder populations. In such populations, however, the relatedness among individuals may be considerable. Neglecting such correlations among individuals can lead to seriously spurious associations. Here, we propose a method for case-control association studies of binary traits that is suitable for any set of related individuals, provided that their genealogy is known. Although we focus here on large inbred pedigrees, this method may also be used in outbred populations for case-control studies in which some individuals are relatives. We base inference on a quasi-likelihood score (QLS) function and construct a QLS test for allelic association. This approach can be used even when the pedigree structure is far too complex to use an exact-likelihood calculation. We also present an alternative approach to this test, in which we use the known genealogy to derive a correction factor for the case-control association chi2 test. We perform analytical power calculations for each of the two tests by deriving their respective noncentrality parameters. The QLS test is more powerful than the corrected chi2 test in every situation considered. Indeed, under certain regularity conditions, the QLS test is asymptotically the locally most powerful test in a general class of linear tests that includes the corrected chi2 test. The two methods are used to test for associations between three asthma-associated phenotypes and 48 SNPs in 35 candidate genes in the Hutterites. We report a highly significant novel association (P=2.10-6) between atopy and an amino acid polymorphism in the P-selectin gene, detected with the QLS test and also, but less significantly (P=.0014), with the transmission/disequilibrium test.  相似文献   

14.
《Bio Systems》2008,91(3):656-675
We try to perform geometrization of cognitive science and psychology by representing information states of cognitive systems by points of mental space given by a hierarchic m-adic tree. Associations are represented by balls and ideas by collections of balls. We consider dynamics of ideas based on lifting of dynamics of mental points. We apply our dynamical model for modeling of flows of unconscious and conscious information in the human brain. In a series of models, Models 1–3, we consider cognitive systems with increasing complexity of psychological behavior determined by structure of flows of associations and ideas.  相似文献   

15.
16.
Two experiments were conducted to investigate the automatic processing of emotional facial expressions while performing low or high demand cognitive tasks under unattended conditions. In Experiment 1, 35 subjects performed low (judging the structure of Chinese words) and high (judging the tone of Chinese words) cognitive load tasks while exposed to unattended pictures of fearful, neutral, or happy faces. The results revealed that the reaction time was slower and the performance accuracy was higher while performing the low cognitive load task than while performing the high cognitive load task. Exposure to fearful faces resulted in significantly longer reaction times and lower accuracy than exposure to neutral faces on the low cognitive load task. In Experiment 2, 26 subjects performed the same word judgment tasks and their brain event-related potentials (ERPs) were measured for a period of 800 ms after the onset of the task stimulus. The amplitudes of the early component of ERP around 176 ms (P2) elicited by unattended fearful faces over frontal-central-parietal recording sites was significantly larger than those elicited by unattended neutral faces while performing the word structure judgment task. Together, the findings of the two experiments indicated that unattended fearful faces captured significantly more attention resources than unattended neutral faces on a low cognitive load task, but not on a high cognitive load task. It was concluded that fearful faces could automatically capture attention if residues of attention resources were available under the unattended condition.  相似文献   

17.
This study examined whether menstrual cycle phase was associated with performance on the Primary Mental Abilities Test of Spatial Relations, a test of mental rotation, in undergraduate students (N = 82). As cortisol levels also vary across the menstrual cycle under conditions of stress and influence cognitive performance, saliva samples were obtained before and after the test session to examine whether cortisol levels were related to between- and within-group differences in spatial performance. Men scored higher on the spatial test than all the groups of women, although the difference between men and women in the menstrual phase was not significant. Women in the luteal phase scored lower than the menstrual, follicular, and oral contraceptive user groups of women. There were no sex or menstrual cycle differences in cortisol levels, and no association between cortisol levels and spatial performance. The poorer performance of women in the luteal phase was not related to differences in ratings of perceived stress, perceived success on the test, or mood. Although menstrual cycle phase accounted for a significant proportion of the variance (15%) in performance on the spatial test, this does not explain why men outperformed women regardless of the phase of the cycle. Thus, there are clearly several other variables, sociocultural and physiological, involved in mediating individual differences in spatial performance.  相似文献   

18.
In this paper we present a novel theory of the cognitive and neural processes by which adults learn new spoken words. This proposal builds on neurocomputational accounts of lexical processing and spoken word recognition and complementary learning systems (CLS) models of memory. We review evidence from behavioural studies of word learning that, consistent with the CLS account, show two stages of lexical acquisition: rapid initial familiarization followed by slow lexical consolidation. These stages map broadly onto two systems involved in different aspects of word learning: (i) rapid, initial acquisition supported by medial temporal and hippocampal learning, (ii) slower neocortical learning achieved by offline consolidation of previously acquired information. We review behavioural and neuroscientific evidence consistent with this account, including a meta-analysis of PET and functional Magnetic Resonance Imaging (fMRI) studies that contrast responses to spoken words and pseudowords. From this meta-analysis we derive predictions for the location and direction of cortical response changes following familiarization with pseudowords. This allows us to assess evidence for learning-induced changes that convert pseudoword responses into real word responses. Results provide unique support for the CLS account since hippocampal responses change during initial learning, whereas cortical responses to pseudowords only become word-like if overnight consolidation follows initial learning.  相似文献   

19.
OBJECTIVE: To investigate the contribution of neuroleptic drugs to cognitive decline in dementia. DESIGN: Two year prospective, longitudinal study consisting of interviews every four months, with necropsy follow up. SETTING: Community settings in Oxfordshire. SUBJECTS: 71 subjects with dementia, initially living at home with informant. MAIN OUTCOME MEASURES: Cognitive function (score from expanded minimental state examination); behavioural problems (physical aggression, hallucinations, persecutory ideas, and disturbance of diurnal rhythm); and postmortem neuropathological assessment (cortical Lewy body pathology). RESULTS: The mean (SE) decline in cognitive score in the 16 patients who took neuroleptics was twice that in the patients who did not (20.7 (2.9) v 9.3 (1.3), P = 0.002). An increased rate of decline was also associated with aggression, disturbed diurnal rhythm, and persecutory ideas. However, only use of neuroleptics and severity of persecutory ideas were independently associated with more rapid cognitive decline when all other variables were adjusted for. The start of neuroleptic treatment coincided with more rapid cognitive decline: median rate of decline was 5 (interquartile range 8.5) points per year before treatment and 11 (12) points per year after treatment (P = 0.02). Cortical Lewy body pathology did not account for association between neuroleptic use and more rapid decline. CONCLUSIONS: Neuroleptic drugs that are sometimes used to treat behavioural complications of dementia may worsen already poor cognitive function. Randomised controlled trials are needed to confirm a causal relation.  相似文献   

20.
This article provides an overview of recent research on human planning and problem solving. As an introduction, these two cognitive domains will be described and discussed from the perspective of experimental and cognitive psychology. The following sections will focus on the role of the prefrontal cortex in planning and problem solving and on disorders of these functions in patients with frontal-lobe lesions. Specific emphasis will be placed on the Tower of London task, a well established and widely used neuropsychological test of planning ability. We will present an overview of recent behavioural and neuroimaging studies that have employed the Tower of London task to draw specific conclusions about the likely neural and cognitive basis of planning function. Finally, we turn to a number of new directions and recent studies exploring different aspects of planning and problem solving and their association to related cognitive dimensions.  相似文献   

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