• Title/Summary/Keyword: cognitive mechanisms

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The Effects of Past Success on Performance: The Mediating Role of Self-Efficacy, Burnout, and Engagement (과거성공이 성과에 미치는 영향 : 자아효능감, 소진, 몰입의 매개역할을 중심으로)

  • Im, Chang-Hee
    • Management & Information Systems Review
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    • v.29 no.1
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    • pp.49-78
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    • 2010
  • Traditionally, self-efficacy, burnout and engagement are defined as work related states of mind, and formally speaking, students are not employees. But, we assume that from a psychological perspective, student core activities can be considered work. Therefore, based on SCT(social cognitive theory), we examine the mediating role of self-efficacy in the prediction of student burnout and engagement, and also the mediation of burnout and engagement between self-efficacy and performance(GPA). There is no research to date wether there would be mediating role of these variables between past success and performance. These effects were analysed in the context of mediating role of the variables in a university in a sample of 438 students. This study utilized a convenience sample drawn from various major scholar area. Results of structural equation modeling analyses were consist with a full mediation model in which academic past success predicts self-efficacy, which in turn, predicts student burnout and engagement. Also our proposed model showed that burnout and engagement are partial or full mediating variables between self-efficacy and performance. Our study's findings provide evidence that engagement fully accounted for the relationship between self-efficacy and performance, and burnout partially explained the relationships. These findings aligns with the general theorizing supported by JD-R model and SCT(social cognitive theory). More specifically, it builds on the JD-R literature as it tests one of the proposed mechanisms in the relationship between job resources and work engagement. Implications of study are discussed, together with limitations and suggestions for future research.

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The Processing of Causative and Passive Verbs in Korean (한국어의 사.피동문 처리에 관한 연구:실어증 환자의 처리 양상을 바탕으로)

  • 문영선;김동휘;남기춘
    • Proceedings of the Korean Society for Cognitive Science Conference
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    • 2000.05a
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    • pp.267-272
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    • 2000
  • 본 연구에서는 한국어의 사·피동문을 실어증 환자가 처리하는 양상에 대하여 살펴보았다. 한국어의 사·피동문은 용언에 파생접사가 붙어 이루어지는 경우와 '-게 하다'나 '-어 지다'와 같이 구문 변형으로 하여, 실어증 환자에게 실험을 하였다. 실험에 참여한 환자는 명칭성 실어증 환자, 이해성 실어증 환자, 표현성 실어증 환자, 전반성 실어증 환자로 구성되어 있다. 본 실험에서는 단어 채워 넣기 과제(word completion task)를 사용하였다. 명칭성 실어증 환자의 경우 피동에서는 처리 오류를 보이는 반면, 사동에는 아무런 문제도 보이지 않았다. 표현성 실어증 환자의 경우, <피동-비변형>에서 오류를 많이 보였다. 이를 통해 한국어의 사·피동은 영어와 달리 통사상의 문제가 아니라는 결론을 내릴 수 있다. 즉 이미 사·피동 접사에 의해 파생된 단어가 어휘부에 저장되어 있고, 각 단어의 논항 정보에 따라 문장이 생성되는 것이다. 표현성 실어증 환자가 피동의 비변형에서 지배적인 오류를 보이는 것은 피동의 비변형이 타동사로서 변형인 피동형에 비해 하나의 논항을 더 취하기 때문이다. 이해성 실어증 환자의 경우 사·피동 생성에 별 어려움을 보이지 않았다. 이는 이해성 실어증 환자가 개별 어휘의 논항 정보에 손실을 적게 입고 있음을 시사하는 결과이다. 본 연구에서는 서로 다른 유형을 보이는 환자들을 대상으로 한국어의 사·피동의 처리양상을 대조한 결과, 첫재 사·피동은 서로 다른 통사, 의미상의 처리 양상을 보이고 있고, 둘째 파생접사가 결합된 형태로 어휘부에 저장되어 있는 개별 사·피동사에 의해 형성되는 것임을 확인하였다.d CO2 quantity causes flame temperature to fall since at high strain retes diluent effect is prevailing and at low strain rates the products inhibits chain branching. It is also found that the contribution of NO production by N2O and NO2 mechanisms are negligible and that thermal mechanism is concentrate on only the reaction zone. As strain rate and CO2 quantity increase, NO production is remarkably augmented.our 10%를 대용한 것이 무첨가한 것보다 많이 단단해졌음을 알 수 있었다. 혼합중의 반죽의 조사형 전자현미경 관찰로 amarans flour로 대체한 gluten이 단단해졌음을 알수 있었다. 유화제 stearly 칼슘, 혹은 hemicellulase를 amarans 10% 대체한 밀가루에 첨가하면 확연히 비용적을 증대시킬 수 있다는 사실을 알 수 있었다. quinoa는 명아주과 Chenopodium에 속하고 페루, 볼리비아 등의 고산지에서 재배 되어지는 것을 시료로 사용하였다. quinoa 분말은 중량의 5-20%을 quinoa를 대체하고 더욱이 분말중량에 대하여 0-200ppm의 lipase를 lipid(밀가루의 2-3배)에 대하여 품질개량제로서 이용했다.

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Attention-induced expansion in visual space (주의에 의한 시각 공간 확장)

  • 유명현;박정선;정찬섭
    • Korean Journal of Cognitive Science
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    • v.10 no.3
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    • pp.51-66
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    • 1999
  • Selective attention induces perceptual distortions. ranging from repulsion of objects located near the attended area(Suzuki & Cavanagh. 1997) to magnification of the u unattended objects (Tsal & Shalev. 1996). Two hypothetical mechanisms have been p postulated: a shift of receptive fields' positions away from the locus of attention(receptive-field-recruitment hypothesis) or the enlargement of perceived space around the a attended location(space-enlargement hypothesis). The present study distinguished between these hypotheses by investigating the spatial and temporal properties of attention-induced d distortions. Perceptual judgements on vernier alignment. line tilt. line length were used to measure attention-induced changes in perception. Attention was induced exogenously(by blinking a specific set of dots around the test stimuli} or endogenously(by instructing the subject to selectively attend the dots). After inducing attention. the test stimuli were briefly flashed. A staircase method was used to measure the attentional effect. A vertical line was perceived as repelled from the locus of attention. and a line segment appeared longer when attention was given to its vicinity. The effects decreased as the distance between the locus of attention or the time between the onset of attention and the stimulus presentation increased. The results imply that the space-enlargement hypothesis provides a better explanation for the attention-induced changes in perception than the receptive-field-recruitment hypothesis.

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Ginseng improves cognitive deficit via the RAGE/NF-κB pathway in advanced glycation end product-induced rats

  • Tan, Xiaobin;Gu, Junfei;Zhao, Bingjie;Wang, Shuyuan;Yuan, Jiarui;Wang, Chunfei;Chen, Juan;Liu, Jiping;Feng, Liang;Jia, Xiaobin
    • Journal of Ginseng Research
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    • v.39 no.2
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    • pp.116-124
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    • 2015
  • Background: Ginseng, the root of Panax ginseng (PG), is used widely as a herbal medicine to prevent and treat various diseases. Panax ginseng has pharmacological effects on neurodegenerative diseases such as Alzheimer's disease (AD). The present study evaluated the neuroprotective effects of PG and its possible neuroprotective mechanisms in advanced glycation end product (AGE)-induced AD in a rat model. Methods: Advanced glycation end products were injected bilaterally into the CA3 region of the rats' brains. The Morris water maze test and step-down type passive avoidance test were performed to evaluate their memory and cognitive abilities. The oxidation indexes in the hippocampus were detected. Immunohistochemistry was conducted to visualize the receptors for advanced glycation end products (RAGEs) and nuclear factor-kappa-light-chain-enhancer of activated B cell (NF-${\kappa}B$). Results: Behavioral results showed that PG (1 g/kg, 0.5 g/kg, and 0.25 g/kg) significantly shortened the escape latency, remarkably increased the number of crossing times, significantly decreased the number of errors, and prolonged the latency in rats with AGE-induced AD. Panax ginseng also significantly reduced the malondialdehyde level, increased the glutathione content, and increased superoxide dismutase activity in the hippocampus. Panax ginseng significantly decreased the expression of RAGE and NF-${\kappa}B$. The blockade of anti-RAGE antibody could significantly reduce AGE-induced impairments and regulate these expressions. Conclusion: Our results demonstrated that PG significantly inhibits AGE-induced memory impairment and attenuates Alzheimer-like pathophysiological changes. These neuroprotective effects of PG may be associated with the RAGE/NF-${\kappa}B$ pathway. Our results provided the experimental basis for applying PG in preventing and treating AD.

Design of Adaptive Security Framework based on Carousel for Cognitive Radio Network (인지무선네트워크를 위한 회전자 기반 적응형 보안프레임워크 설계)

  • Kim, Hyunsung
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.5
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    • pp.165-172
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    • 2013
  • Convergence is increasingly prevalent in the IT world which generally refers to the combination of two or more different technologies in a single device. Especially, the spectrum scarcity is becoming a big issue because there are exponential growth of broadcasting and communication systems in the spectrum demand. Cognitive radio (CR) is a convergence technology that is envisaged to solve the problems in wireless networks resulting from the limited available spectrum and the inefficiency in the spectrum usage by exploiting the existing wireless spectrum opportunistically. However, the very process of convergence is likely to expose significant security issues due to the merging of what have been separate services and technologies and also as a result of the introduction of new technologies. The main purpose of this research is focused on devising an adaptive security framework based on carousel for CR networks as a distinct telecommunication convergence application, which are still at the stage of being developed and standardized with the lack of security concerns. The framework uses a secure credential, named as carousel, initialized with the location related information from objects position, which is used to design security mechanisms for supporting privacy and various securities based on it. The proposed adaptive security framework could be used as a security building block for the CR network standards and various convergence applications.

A Study on the Brain Scientific Mechanism of Drawing Education - Focusing on the Animated Drawing (드로잉 교육의 뇌과학적 기제 연구 - 애니메이션 드로잉을 중심으로)

  • Park, Sung Won
    • Cartoon and Animation Studies
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    • s.36
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    • pp.217-236
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    • 2014
  • This study is a literature analytical process for studying the drawing teaching methods considering the professional characteristics of animation and a principle analytical process for studying the perspective that when teaching methods that consider the function, learning and creative mechanisms of the brain are applied, the animation drawing ability will be effectively increased. In recent years, as an alternative discussion on the educational method of each field, study results applied with brain-based learning principles are being presented. This is not only being applied and implemented for art and drawing education but as overall educational alternatives. On the other hand, animation drawing requires artistic literacy and at the same time requires comprehensive teaching methods that can train the structural knowledge, cognitive sensation and communication method but such professional teaching methods are insufficient. Therefore, the principle of effective education is seen through the brain mechanism and the principle of demonstrating the creativity and learning by the brain is analyzed. In addition, through the fundamental relationship on the picture drawing and the function of the brain, the relationship of the drawing and the brain is identified. As a result, not only for the left brain that observes the cognitive information which can draw the structure and shapes but the right brain which is directly related to the drawing should be developed, but in order to express the creativity, teaching methods that can understand the mechanism of comprehensive brain where physical and psychological factors are expressed should be also developed. It is because the animation drawing education is teaching the methods for demonstrating the characteristics of artistic creativity required for the drawing ability. This process will not only be a foundation for identifying the difference against the previous animation drawing teaching methods, and the brain-based principles will be selected as the core strategic definition for designing the strategy and methodological model of future education.

Elementary and Secondary School Teachers' Polar Literacy (초·중등학교 교사들의 극지 소양)

  • Chung, Sueim;Choi, Haneul;Kim, Minjee;Shin, Donghee
    • Journal of the Korean earth science society
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    • v.42 no.6
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    • pp.734-751
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    • 2021
  • The purpose of this study is to prepare basic data to reflect polar literacy education in the school curriculum. The perception about the polar regions, teaching experience, and polar-related cognitive and affective characteristics of teachers were investigated. The survey was conducted among 56 elementary, middle, and high school teachers from schools from 10 major cities and surrounding regions, based on their perceptions of the polar region, current teaching status, polar knowledge, and beliefs and attitudes toward polar region and climate change. Results showed that although teachers' polar information efficacy was low, they positively evaluated the status of educators in resolving polar and climate change problems, and prioritized global citizenship values over practical purposes. The experience of teaching polar region and climate change issues at schools varied across subjects and non-subjects, but showed a passive aspect in teaching development, such as wanting to be provided with consolidated learning materials. On the cognitive aspect, teachers revealed an ambiguous understanding of the mechanisms and processes by which polar change and climate influence each other. On the affective aspect, most teachers showed strong beliefs and attitudes for polar-related issues beyond the school level, but their behavior choices were relatively lower. Based on the results, we propose the following as recommendations: providing opportunities and materials to promote polar knowledge, discovering educational materials in various contexts to form values and attitudes, developing educational materials from polar research materials, identifying misconceptions about polar knowledge among students and teachers, strengthening elementary school teachers' polar literacy, and cultivating positive attitudes and values toward polar issues.

Integrative analysis of microRNA-mediated mitochondrial dysfunction in hippocampal neural progenitor cell death in relation with Alzheimer's disease

  • A Reum Han;Tae Kwon Moon;Im Kyeung Kang;Dae Bong Yu;Yechan Kim;Cheolhwan Byon;Sujeong Park;Hae Lin Kim;Kyoung Jin Lee;Heuiran Lee;Ha-Na Woo;Seong Who Kim
    • BMB Reports
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    • v.57 no.6
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    • pp.281-286
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    • 2024
  • Adult hippocampal neurogenesis plays a pivotal role in maintaining cognitive brain function. However, this process diminishes with age, particularly in patients with neurodegenerative disorders. While small, non-coding microRNAs (miRNAs) are crucial for hippocampal neural stem (HCN) cell maintenance, their involvement in neurodegenerative disorders remains unclear. This study aimed to elucidate the mechanisms through which miRNAs regulate HCN cell death and their potential involvement in neurodegenerative disorders. We performed a comprehensive microarray-based analysis to investigate changes in miRNA expression in insulin-deprived HCN cells as an in vitro model for cognitive impairment. miR-150-3p, miR-323-5p, and miR-370-3p, which increased significantly over time following insulin withdrawal, induced pronounced mitochondrial fission and dysfunction, ultimately leading to HCN cell death. These miRNAs collectively targeted the mitochondrial fusion protein OPA1, with miR-150-3p also targeting MFN2. Data-driven analyses of the hippocampi and brains of human subjects revealed significant reductions in OPA1 and MFN2 in patients with Alzheimer's disease (AD). Our results indicate that miR-150-3p, miR-323-5p, and miR-370-3p contribute to deficits in hippocampal neurogenesis by modulating mitochondrial dynamics. Our findings provide novel insight into the intricate connections between miRNA and mitochondrial dynamics, shedding light on their potential involvement in conditions characterized by deficits in hippocampal neurogenesis, such as AD.

Revisiting the Effect of Syllable Transposition in Korean Word Recognition: Disentangling Orthographic and Morphological Influences (한글 단어 재인에서 음절 전위 효과의 재검토: 표기 처리와 형태소 처리의 영향 분석)

  • Sungbong, Bae;Chang H. Lee
    • Korean Journal of Cognitive Science
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    • v.35 no.3
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    • pp.161-185
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    • 2024
  • The letter transposition effect is crucial for understanding whether letter position coding within words is fixed. Despite the recognized importance of syllables in Korean word recognition, studies on syllable transposition effects have been inconsistent, indicating a lack of clarity on its mechanisms. Our study aims to address this by analyzing the syllable transposition effect, with a particular focus on distinguishing the influences of orthographic from morphological processing. This focus is due to Korean syllables serving simultaneously as units of orthography and elements of morphology. Through a masked priming lexical decision task with bisyllabic words, we conducted two experiments. Experiment 1 examined the effect across various word types to assess the impact of word origin, while Experiment 2 directly compared the influences of morphological and semantic processing. Results from both experiments showed a significant syllable transposition effect across all word types, pointing to orthographic processing as the key factor in the effect, rather than morphological or semantic factors. This underscores the flexibility of syllable position coding in the early stages of word processing and emphasizes orthographic processing as the primary influence on the syllable transposition effect.

C-fos mRNA Expression in Rat Hippocampal Neurons by Antidepressant Drugs (배양한 흰쥐 해마신경세포에서 항우울제에 의한 c-fos mRNA의 발현)

  • Park, Eung-Chul;Cho, Yun-Gyoo;Yang, Byung-Hwan;Kim, Kwang-Iel;Yang, Bo-Gee;Chai, Young-Gyu
    • Korean Journal of Biological Psychiatry
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    • v.8 no.1
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    • pp.85-95
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    • 2001
  • This study was designed to examine the effects of two antidepressant drugs on the expression of c-fos mRNA in cultured embryonic rat hippocampal neurons. The drugs used were imipramine and amitriptyline. On the fourth day of culture, hippocampal neurons were treated with variable concentrations of each drug. Competitive RT-PCR(Reverse Transcriptase-PCR) analysis was used to quantify the c-fos mRNA expression induced by each drug. Experimental results showed that acute and direct treatment with imipramine and amitriptyline with relatively low concentrations(imipramine ${\leq}10{\mu}M$, amitriptylne ${\leq}10{\mu}M$) had no inductive effect on the expression of c-fos mRNA in the rat hippocampal neurons. However, after treatment with relatively high concentrations(imipramine ${\geq}100{\mu}M$, amitriptyline ${\geq}100{\mu}M$) c-fos mRNA was not detected. These findings suggest the followings. Firstly, the action mechanisms of these drugs on the hippocampal neurons might not be mediated by c-fos but by other immediate-early genes(IEGs). Secondly, their actions may be mediated indirectly via other areas of the brain. Thirdly, the expression of c-fos might be inhibited by high concentrations of these drugs, or the high concentrations could induce cell death. Finally, though cell death remains to be confirmed, the inhibition of c-fos induction or cell death could play a role in the cognitive impairments known to be adverse effects of some antidepressants. This study is believed to be a first step toward understanding the mechanisms of learning and memory. Further studies are needed to investigate the expression of various IEGs and changes in the hippocampal neurons of rat resulting from chronic treatment with antidepressant drugs.

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