• Korean Journal of Cognitive Science
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• v.33 no.2
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• pp.109-133
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• 2022

Episodic memory consists of a core event and the associated contexts. Although the role of the hippocampus and its neighboring regions in contextual representations during encoding has become increasingly evident, it remains unclear how these regions handle various context-specific information other than spatio-temporal contexts. Using high-resolution functional MRI, we explored the patterns of the medial temporal lobe (MTL) and cortical regions' involvement during the encoding of various types of contextual information (i.e., journalism principle 5W1H): "Who did it?," "Why did it happen?," "What happened?," "When did it happen?," "Where did it happen?," and "How did it happen?" Participants answered six different contextual questions while looking at simple experimental events consisting of two faces with one object on the screen. The MTL was divided to sub-regions by hierarchical clustering from resting-state data. General linear model analyses revealed a stronger activation of MTL sub-regions, the prefrontal lobe (PFC), and the inferior parietal lobule (IPL) during social (Who), behavioral (How), and intentional (Why) contextual processing when compared with spatio-temporal (Where/When) contextual processing. To further investigate the functional networks involved in contextual encoding dissociation, a multivariate pattern analysis was conducted with features selected as the task-based connectivity links between the hippocampal subfields and PFC/IPL. Each social, behavioral, and intentional contextual processing was individually and successfully classified from spatio-temporal contextual processing, respectively. Thus, specific contexts in episodic memory, namely social, behavior, and intention, involve distinct functional connectivity patterns that are distinct from those for spatio-temporal contextual memory.

• The Korean Journal of Food And Nutrition
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• v.27 no.4
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• pp.673-677
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• 2014

HX106N은 용안육, 맥문동, 단삼 및 천마 등의 4가지 식물로 구성된 추출물로서, 선행 연구에서 amyloid ${\beta}$ peptide에 의한 생쥐의 기억력 저하 및 산화 손상을 억제하는 것으로 밝혀졌다. 이 연구에서는 HX106N이 비선택적 무스카린 수용체 길항제로 잘 알려진 스코폴라민(scopolamine)으로 유도한 콜린성 건망증(cholinergic amnesia)에 어떤 영향을 미치는지를 평가하였다. ICR 생쥐에게 스코폴라민(1 mg/kg body weight, i.p.)을 주입하기 1시간 전에 HX106N(100 mg/kg body weight, p.o.)을 투여하였다. 30분 후 수행한 Y-미로 시험(Y-maze test) 및 수동 회피 시험(passive avoidance test)에서 HX106N는 스코폴라민에 의해 감소되는 자발적 변경 행동(spontaneous alternation) 및 지체시간(step-through latency)을 유의미하게 억제하여 건망증을 개선시키는 것으로 나타났다. 또한 HX106N을 투약 1시간 후 생쥐의 해마와 대뇌피질 부위의 아세틸콜린에스테라제(acetylcholinesterase; AChE)의 활성을 측정한 결과 통계적으로 유의미한 정도의 활성 감소가 관찰되었다. 이러한 결과들을 종합할 때 HX106N은 AD에서 관찰되는 콜린성신경전달 장애로 인한 기억력 저하 억제에 사용될 수 있는 가능성을 가진 것으로 판단된다.

• Therapeutic Science for Rehabilitation
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• v.3 no.1
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• pp.67-77
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• 2014

Objective : The purpose of this study was to examine task-oriented training affects on instrumental activity of daily living for elderly with dementia. Methods : The participant is a 75 years old female with dementia. The intervention was performed for 45 minute on 3 times per week over 1 month. Independent variable was task-oriented training and dependent variable were memory(DST), executive function(TMT-A, CDT), changing of IADL(AMPS). Results : The results showed that the participant significantly improved in executive function, performance of IADL. However, the participant did not show significant improvement in memory. Conclusion : In conclusion, the findings of this study indicate that task-oriented training is positive effect on performance of IADL in dementia.

• Journal of Biosystems Engineering
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• v.15 no.3
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• pp.186-198
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• 1990

인간 소뇌의 구조와 기능을 간략하게 수학적으로 모델링하여 입력에 따른 시스템의 적정 출력을 학습에 의한 적응 제어 방식으로 추출해 내는 소뇌모델 대수제어기(CMAC : Cerebellar Model Arithmetic Controller)가 제안되었다. 본 논문에서는 연구개발된 기존 신경회로망과의 비교 분석에 의거하여, 소뇌모델 대수제어기 대신 네트의 특성에 따라 소뇌모델 선형조합 신경망(CMLAN : Cerebellum Model Linear Associator Network)이라 하였다. 소뇌모델 선형조합 신경망은 시스템의 제어 함수치를 결정하는 데 있어, 기존의 제어방식이 시스템의 모델링을 기초로 하여 알고리즘에 의한 수치해석적 또는 분석적 기법으로 모델 해를 산출하는 것과 달리, 학습을 통하여 저장되는 분산기억 소자들의 함수치를 선형적으로 조합함으로써 시스템의 입출력을 결정한다. 분산기억 소자로의 함수치 산정 및 저장은 소뇌모델 선형조합 신경망이 갖는 고유의 구조적 상태공간 매핑(State Space Mapping)과 델타규칙(Delta Rule)에 의거한 시스템의 입출력 상태함수의 학습으로써 수행된다. 본 논문을 통하여 소뇌모델 선형조합신경망의 구조적 특성, 학습 성질과 상태공간 설정 및 시스템의 수렴성을 규명하였다. 또한 기존의 최대 편차수정 학습 알고리즘이 갖는 비능률성 및 적용 제한성을 극복한 효율적 학습 알고리즘들을 제시하였다. 언급한 신경망의 특성 및 제안된 학습 알고리즘들의 능률성을 다양한 학습이득(Learning Gain)하에서 비선형 함수를 컴퓨터로 모의 시험하여 예시하였다.

• Korean Journal of Cognitive Science
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• v.34 no.4
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• pp.299-314
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• 2023

This study aimed to examine whether there are differences in reading performance between digital and print media by measuring reading speed of paragraphs on print materials and tablet PC. To investigate whether the physical characteristics of the media influence reading performance, the format of text was kept as similar as possible between print and digital media. We also compared conditions in which paragraphs consisted of either long or short sentences to explore if there were differential effects on reading performance based on sentence length across different media. Additionally, reading speed was analyzed based on reading span to investigate whether there were differences in reading performance according to participants' working memory capacity. As a result, reading speed was faster when reading print media compared to digital media. However, there was no difference in reading speed based on the length of sentences composing the paragraphs. Participants with a higher reading span exhibited faster reading speed compared to participants with a lower reading span. Moreover, participants with a higher reading span read paragraphs composed of long sentences faster on print media than on digital media. The findings of this study suggest that visual fatigue induced by tablet PCs and participants' working memory capacity may impact reading speed.

• Journal of Science Education
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• v.36 no.2
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• pp.167-185
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• 2012

This study aimed at finding points of improvement in teaching expertise by analyzing the question patterns that appeared during teaching demonstrations which applied science teaching models prepared by a pre-service biology teacher. The question analysis frame for analyzing question types were categorized largely into the question types of Category 1 (questions in cognitive domain, questions with research function, questions in affective domain), Category 2 (repeated questions, questions for narrowing the range, practice questions), and Category 3 (questions on student activity progress, memory questions, and thinking questions). The results of analyzing question patterns from five different science teaching models revealed a high frequency of questions in the fields of cognition and memory. For the circular learning model, questions from the cognitive field appeared the most often, while, student activity progressive questions in particular were used mostly in the 'preliminary concept introduction stage' of the circular learning model and the 'secondary exploratory stage', in which experiments were conducted, and displayed the characteristics of these stages. The discovery learning model combined the courses of observation, measurement, classification and generalization, but, during teaching demonstrations, memory questions turned up the most, while the portion of inquisitive function questions was low. There were many questions from the inquisitive learning model, and, compared to other learning models, many exploratory function questions turned up during the 'experiment planning stage' and 'experiment stage'. Definitional questions and thought questions for the STS learning model turned up more than other learning models. During the change of concept learning model, the five concepts of students were stimulated and the modification of scientific concepts was very much aided by using many memory questions.

• Journal of the Korea Computer Graphics Society
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• v.6 no.3
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• pp.25-34
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• 2000

본 논문에서는 점진적 메쉬의 보다 엄밀한 의미에서의 선택적 세분화 방법을 제안한다. 기존의 선택적 세분화 방법은 정점분할 및 에지붕괴 연산이 수행되기 위해서는 현재의 1-고리 이웃 상황이 점진적 메쉬 분석 단계에 기억해 놓은 1-고리 이웃과 같을 때만 올바로 동작하도록 되어 있는 증가적 방법이다. 이러한 증가적 방법은 메쉬의 부분적 해상도 변경을 하게 되면 인접한 부분의 해상도가 그 부분의 해상도를 좇아가게 되는 단점을 가지고 있다. 본 논문에서 제안하는 방법은 점진적 메쉬 표현이 가지는 정점의 계층적 구획화 성질에 기반한 것으로, 원하는 메쉬의 부분에 대해 해상도를 변경할 때, 인접 부분의 정점분할 및 에지붕괴 연산을 초래하지 않아 보다 엄밀한 의미에서의 점진적 메쉬의 선택적 세분화를 수행할 수 있다.

• Therapeutic Science for Rehabilitation
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• v.10 no.4
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• pp.81-94
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• 2021

Objective : Response time plays a prominent part in research on cognitive ability and the aging effect. This study aimed to identify the impact of cognitive ability on information processing by conducting cognitive response time (CRT) using a computer program. Methods : This study was conducted in 30 normal elderly (NE) and 30 elderly with amnestic MCI (aMCI), aged 65-79 years old living in Daegu and Gyeongbuk. The results were analyzed using the statistical analysis program R 4.0.2 (University of Auckland, New Zealand). Results : In the three sub-areas of CRT, the total response time showed a significant difference depending on group or age, and the error rate showed a significant difference depending on age or group in some sub-areas. In the aMCI group, the performance of CRT significantly correlated with that of the overall cognition and memory test. Conclusion : Information processing depending on aging or cognitive ability and the differential performance of processing speed could be observed through CRT. The performance of this test was found to be significantly correlated with that of the overall cognition and memory test. Therefore, CRT could be used meaningfully as a simplified tool to predict the initial cognitive disorder of the elderly in the community.

• Korean Journal of Cognitive Science
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• v.23 no.1
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• pp.25-46
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• 2012

When performing a monotonous task, one often experiences an urge to quit. This urge may vary depending on how long one has performed the task (a temporal factor) and on which particular component of the task one is carrying out (an event-based factor). Using the Stroop task and a working memory task, we examined changes in the urge to quit as a function of basic temporal (repetition) and event-based (cognitive conflict) factors. Consistent with the law of least work and recent theorizing, for the memory task, urges to quit were greater following difficult trials; for the Stroop task, urges to quit were greater following incongruent than congruent trials, but only during early/novice phases of performance, when responding is inefficient. This is a demonstration of an avoidance response toward cognitive conflict. Regarding temporal sources of quitting, urges to quit were greater for late task stages than early stages. These basic findings may illuminate the nature of the more 'hot' motivational struggles involving the delay of gratification.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2001.11a
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• pp.255-259
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• 2001

본 연구에서는 긍/부정 판단 과제 시 연령간 뇌파 반응의 차이를 밝히고자 한다. 실험 대상의 연령은 10명(20대 5명, 60대 5명)이었으며, 모두 오른손잡이였다. 실험과제는 의미과제와 일화과제로 구분되며 각각 12문항으로 구성된다. 의미기억과제 덧셈문제를, 일화기억 과제는 도형을 이용하였으며, 마우스 버튼을 눌러 긍/부정 판단 반응을 하도록 하였다. 뇌파는 PE1, PF2, F3, F4, O1, O2에서 단극유도법으로 측정되었으며, EOG를 측정하여 뇌파분석 시에 눈 깜박임으로 인하 noise를 제거하도록 하였다. 뇌파 분석은 원자료를 FFT(Fast Fourier Transformation)를 수행하여 각 대역의 상대적인 power를 구하는 방법으로 이루어졌다. 분석 결과, 반응 시간은 긍/부정판단간의 차이는 없었으나, 두 과제 모두에서 연령별로 유의미한 차이가 있었다. 긍/부정판단간의 따른 뇌파 반응은 명확한 차이가 나타나지 않았다. 연령에 따른 뇌파반응은 theta파, slow beta, fast beta에서 유의한 차이가 나타났다.