• Animal cells and systems
• /
• v.14 no.1
• /
• pp.11-15
• /
• 2010

Long-term working memory (LTWM) is a subdivision concept of working memory and indicates the enhancement of performance in a working memory task. LTWM has been shown in humans who have been engaged in a specific task requiring working memory over a long time. However, there is very little understanding of the exact mechanism of LTWM because of limitations of experimental methods in human studies. We have modified the standard T-maze task, which is used to test working memory in mice, to demonstrate LTWM in an animal model. We observed an enhancement of performance by repeated experience with the same working memory load in mice, which can be regarded as an LTWM. This effect seems to depend on the condition wherein a delay was given. This task may be a good experimental protocol to assess LTWM in animal studies.

• Sleep Medicine and Psychophysiology
• /
• v.4 no.1
• /
• pp.1-14
• /
• 1997

This paper reviewed models to explain memory and neuropsychological tests to assess memory. Memory was explained in cognitive and neuroanatomical perspectives, Cognitive model describes memory as structure and process. In structure model, memory is divided into three systems: sensory memory, short-term memory(working memory), and long-term memory. In process model, there are broadly three categories of memory process: encoding, storage, and retrieval. Memory process work in memory structure. There are two prominent models of the neuroanatomy of memory, derived from the work of Mishkin and Appenzeller and that of Squire and Zola-Morgan. These two models are the most useful for the clinician in part because they take into account the connections between the limbic and frontal cortical regions. The major difference between the two models concerns the role of the amygdala in memory processess. Mishkin and his colleagues believe that the amygdala plays a significant role while Squire and his colleagues do not. The most popular and widely used tests of memory ability such as WMS-R, AVLT, CVLT, HVLT. RBMT, CFT, and BVRT-R, were reviewed.

• The Mathematical Education
• /
• v.52 no.1
• /
• pp.19-41
• /
• 2013

What is the foundation of mathematical thinking? Is it logic based symbolic language system? or does it rely more on mental imagery and visuo-spatial abilities? What kind of neural changes happen if someone's mathematical abilities improve through practice? To answer these questions, basic cognitive processes including long term memory, working memory, visuo-spatial perception, number processes are considered through neuropsychological outcomes. Neuronal changes following development and practices are inspected and we can show there are neural networks critical for the mathematical thinking and development: prefrontal-anterior cingulate-parietal network. Through these inquiry, we can infer the answer to our question.

• Animal cells and systems
• /
• v.2 no.1
• /
• pp.65-69
• /
• 1998

The hippocampus and prefrontal cortex are regarded as the highest-order association cortices. The hippocampus has been proposed to store "cognitive maps" of external environments, and the prefrontal cortex is known to be involved in the planning of behavior, among other functions. Considering the prominent functional roles played by these structures, it is not surprising to find direct monosynaptic projections from the hippocampus to the prefrontal cortex. Rhythmic stimulation of this projection patterned after the hippocampal EEG theta rhythm induced stable long-term potentiation of field potentials in the prefrontal cortex. Comparison of behavioral correlates of hippocampal and prefrontal cortical neurons during an a-arm radial maze, working memory task shows a striking contrast. Hippocampal neurons exhibit clear place-specific firing patterns, whereas prefrontal cortical neurons do not show spatial selectivity, but are correlated to different stages of the behavioral task. These data lead to the hypothesis that the role of hippocampal projection to the prefrontal cortex is not to impose spatial representations upon prefrontal activity, but to provide a mechanism for learning the spatial context in which particular behaviors are appropriate.propriate.

• Biomolecules & Therapeutics
• /
• v.23 no.3
• /
• pp.251-260
• /
• 2015

Propofol is an anesthetic agent that gained wide use because of its fast induction of anesthesia and rapid recovery post-anesthesia. However, previous studies have reported immediate neurodegeneration and long-term impairment in spatial learning and memory from repeated neonatal propofol administration in animals. Yet, none of those studies has explored the sex-specific long-term physical changes and behavioral alterations such as social (sociability and social preference), emotional (anxiety), and other cognitive functions (spatial working, recognition, and avoidance memory) after neonatal propofol treatment. Seven-day-old Wistar-Kyoto (WKY) rats underwent repeated daily intraperitoneal injections of propofol or normal saline for 7 days. Starting fourth week of age and onwards, rats were subjected to behavior tests including open-field, elevated-plus-maze, Y-maze, 3-chamber social interaction, novel-object-recognition, passive-avoidance, and rotarod. Rats were sacrificed at 9 weeks and hippocampal protein expressions were analyzed by Western blot. Results revealed long-term body weight gain alterations in the growing rats and sex-specific impairments in spatial (female) and recognition (male) learning and memory paradigms. A markedly decreased expression of hippocampal NMDA receptor GluN1 subunit in female- and increased expression of AMPA GluR1 subunit protein expression in male rats were also found. Other aspects of behaviors such as locomotor activity and coordination, anxiety, sociability, social preference and avoidance learning and memory were not generally affected. These results suggest that neonatal repeated propofol administration disrupts normal growth and some aspects of neurodevelopment in rats in a sex-specific manner.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.20 no.12
• /
• pp.85-91
• /
• 2021

In our daily life, artificial intelligence performs simple and complicated tasks like us, including operating mobile phones and working at homes and workplaces. Artificial intelligence is used in industrial technology for diagnosing various types of equipment using the machine learning technology. This study presents a fault mode effect analysis (FMEA) of start motors using machine learning and big data. Through multiple data collection, we observed that the primary failure of the start motor was caused by the melting of the magnetic switch inside the start motor causing it to fail. Long-short-term memory (LSTM) was used to diagnose the condition of the magnetic locations, and synthetic data were generated using the synthetic minority oversampling technique (SMOTE). This technique has the advantage of increasing the data accuracy. LSTM can also predict a start motor failure.

• Journal of Oriental Neuropsychiatry
• /
• v.9 no.2
• /
• pp.19-35
• /
• 1998

Some oriental medicine turned out to have a significant clinical effect on the cure for dementia. Therefore, thorough scientific tests for physiological effect of oriental medicne are needed. This study is aimed at doing experimental studies on the effects of two medicines, Jowiseungcheongtang and hyungbangjihwangtang, on the cure for dementia.For the demonstration of the effect of the two medicines on aged rats, we perfomed a radial arm medicines on aged rats, water maze task, known for their proper learning paradigm for behavior.Previous studies on aging and dementia show that aged rats displayed significant impariments in the learning of the radial arm maze task compared with younger rats. As in experiment 1, we found that the learning of the radial arm maze task compared with younger rats. As in experiment 1, we found that the learning deficits aged rats exhibit in radial arm maze task were improved with the application of each medicine. The resutls suggest that these two medicine can be effective to patients whose working or shortterm memory is impaired. In experiment 2 we studied the effect of the two medicines on the deficit of the aged rats with the Morris water maze task known for measuring long-tern memory. We did not find significant results between the performance of the ages rats and the younger ones. Considered the different results previous studies have reported, more thorough studies are needed to investigate the effect of the medicines on long-term memory.In conclusion, the results we found in experiment 1 and 2 suggest that Jowisengcheongtang and hyungbangjihwangtang can have useful effects for the cure of age-related memory (especially for short-term memory)deficits. Recent interests in dementia urges researchers concerned to explore the effect of oriental medicine on the disease. As there have been relatively few behavioral or scientific studies on dementia using oriental medicine to date, further studies are expected are expected to continue to elucidate 'what the wisdom of the oriental medicine tells about dementia'.

• The Korean Journal of Financial Management
• /
• v.25 no.3
• /
• pp.111-130
• /
• 2008

This paper compares long term equilibrium relation of KOSPI 200 which is underling stock and its futures by using general method fractional cointegration instead of existing integer cointegration. Existence of integer cointegration between two price time series gives much wider information about long term equilibrium relation. These details grasp long term equilibrium relation of two price time series as well as reverting velocity to equilibrium by observing difference coefficient of error term when it renounces from equilibrium relation. The result of this study reveals existence of long term equilibrium relation between KOSPI200 and futures which follow fractional cointegration. Difference coefficient, d, of 'two price time series error term' satisfies 0 < d < 1/2 beside bandwidth parameter, m(173). It means two price time series follow stationary long memory process. This also means impulse effects to balance price of two price time series decrease gently within hyperbolic rate decay. It indicates reverting speed of error term is very low when it bolts from equilibrium. It implies to market maker, who is willing to make excess return with arbitrage trading and hedging risk using underling stock, how invest strategy should be changed. It also insinuates that information transition between KOSPI 200 Index market and futures market does not working efficiently.

• Korean Medical Education Review
• /
• v.12 no.2
• /
• pp.27-33
• /
• 2010

The purpose of this study was to review the definition of cognitive load (CL), the relationship between CL and instructional design, and to provide a viewpoint of CL in curriculum and instructional design in medical education. Cognitive load theory (CLT) makes use of three hypotheses about the structure of human memory: working memory (WM) is limited in terms of the amount of information it can hold, in contrast with WM, long term memory is assumed to have no limits and organizes information as schemata. CL indicates the mental load on the limitation of WM. CLT has been used to design instructional interventions that help to ease the learning process. Extraneous CL is related to irrelevant instructional interventions, while intrinsic CL is the complexity of the information itself. Germane CL is the cognitive process for acquiring schema formation. It is a necessary CL to achieve deeper comprehension and solve problems. The range of medical education includes complex, multifaceted and knowledge-rich domains with clinical skills and attitudes. Therefore, CLT may be used to guide instructional design in medical education in terms of decreasing extraneous CL, adjusting intrinsic CL and enhancing the germane CL.

• Journal of Digital Convergence
• /
• v.19 no.1
• /
• pp.355-360
• /
• 2021

In this study, the factors of confirmation bias that may occur in the initial user experience stage were analyzed using a honeycomb model by deriving user experience factors for each factor. In the initial user experience stage, confirmation bias occurs in the impression stage. At the processing stage of memory, sensory memory, working memory, and long-term memory, which stores and retrieves selective memory, were closely related. Confirmation bias was classified into visibility, correlation, memory, clarity, and universality in the usability part, and satisfaction, joy, and dissatisfaction were derived as emotional factors. As a result of the analysis with the honeycomb model, visuality, clarity, universality in the usability factor, and joy in the emotional factor had little effect on the confirmation bias, and satisfaction and dissatisfaction were analyzed as the main factors of the confirmation bias in the correlation, memory and emotional factors. This study is meaningful in that it can be usefully used as a reference material for companies that customize design patterns for the factor of confirmation bias.