• Korean Journal of Cognitive Science
• /
• v.17 no.3
• /
• pp.207-229
• /
• 2006

Two experiments examined the relation of working memory capacity and the inhibition mechanism in working memory. Experiment 1 demonstrated that the high WM span group inhibited irrelevant information selectively and the low WM span group maintained both relevant and irrelevant information within WM. Experiment 2 showed that there were similar patterns of response time between high and low WM span groups in the lexical decision task. These results suggest that the ability to maintain relevant information and inhibit irrelevant information selectively in WM is an important factor of individual differences in working memory.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.15 no.1
• /
• pp.82-90
• /
• 2004

Objectives：The study was performed to compare the executive function(EF；Inhibition, Planning and Working memory) between ADHD and normal group, and to controll the effect of age and intelligence. And the function of inhibition was assessed in two dimensions(cognitive inhibition and motor inhibition). Methods：K-WISC III and EF test(Go-No-Go, Stroop test, Tower of Hanoi, Digit) was administered to both 25 children with ADHD and 25 normal control participants, all aged between 7 and 12. The results were analyzed after statistically controlled for age and intelligence. Results：Children in the ADHD group had significantly lower IQ score than those in the control group and consistent relations were found between the child's age and the study's major variables. Once IQ and age were controlled, results indicated that children with ADHD had deficit only cognitive inhibition and motor inhibition. There was no significant difference in planning and working memory. Conclusion：These results suggested that specific deficits in inhibition control rather than general EF deficits are associated with ADHD. So inhibition is the core problem of children with ADHD. Thus, the therapeutic approach focused on cognitive inhibition and motor inhibition is required.

• Korean Journal of Cognitive Science
• /
• v.34 no.1
• /
• pp.21-38
• /
• 2023

The present study was designed to investigate the effect of the difficulty level of retrieval practice and the association strength of categories and stimuli within categories on memory inhibition. Most of the studies have investigated whether inhibition was occurred by manipulating the degree of association strength, emotion value or physical characteristics of non-retrieval practice words within the retrieval practice category. Therefore, it was necessary to study how inhibition occurs according to the degree of difficulty of retrieval stimuli during retrieval practice. The difficulty of retrieval was manipulated into three levels: difficult condition, normal condition, and easy condition through the degree of presentation of consonants and vowels of words during retrieval learning. Additionally, the strength of association between categories and words within categories was manipulated. In previous studies, retrieval-induced forgetting occurred under conditions where the association strength between categories and words within the categories was strong. On the other hand, retrieval-induced forgetting did not occur under conditions where the association strength between categories and words within the categories was weak. The present study, if the inhibition process differs according to the difficulty of retrieval, the possibility of different results from previous studies was explored according to the difference in the strength of association with the category. As a result of the study, in the condition of strong association strength, retrieval-induced forgetting was observed under normal and difficult retrieval difficulty conditions. Whereas retrieval-induced forgetting was not observed under conditions of easy retrieval difficulty condition. In the condition of weak association strength, retrieval-induced forgetting tended to occur under difficult retrieval difficulty conditions. Whereas retrieval-induced forgetting was not observed under conditions of normal and easy retrieval difficulty condition. These results suggest that memory inhibition may appear differently depending on the difficulty of retrieval.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.23 no.1
• /
• pp.7-13
• /
• 2003

A hot press method was use for the optimal manufacturing condition for a shape memory alloy(SMA) composite. The bonding between the matrix and the reinforcement within the SMA composite by the hot press method was strengthened by cold rolling. In this study, the objective was to develop an on-line monitoring system for the prevention of the crack initiation and propagation by shape memory effort of SMA composite. Shape memory effect was used to prevent the SMA composite from cracking. For the system to be developed, an optimal hE parameter should be determined based on the degree of damage and crack initiation. When the SHA composite was heated by the plate heater attached at the composite, the propagating cracks appeared to be controlled by the compressive force of SMA.

• Science of Emotion and Sensibility
• /
• v.6 no.3
• /
• pp.21-28
• /
• 2003

This study investigated the differences in processing type of working memory between experts and novices when they read music scores. Two experiments were conducted with the articulatory suppression condition. In Experiment 1, eight half notes were shown on the screen for a brief period of time, participants were then requested to write the notes on a music sheet. the stimuli were divided into two: melodious and unmelodious. In similar fashion, Experiment 2 consisted of four-chord sequences, which contained three notes each. The stimuli were also divided into two: harmonious and disharmonious. As an analysis of the results in Experiment 1 & 2, novices commonly showed better performances in the non-articulatory suppression condition than the articulatory suppression condition with both stimuli types. However, experts were relatively affected little by the articulatory suppression with harmonious stimuli. These findings support that while novices entirely depend on the articulatory loop, experts may encode the notes through the visuo-spatial sketchpad before they transfer the information to the phonological store when they are familiar with material.

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

• Journal of Life Science
• /
• v.23 no.11
• /
• pp.1381-1387
• /
• 2013

The leaves and roots of Ligularia stenocephala, which are widely used as a food in Korea, were investigated for their antioxidant activities and cytotoxicity in vitro, and their hepatoprotective effect, alcohol detoxicant efficacy, and memory-enhancing property were investigated in vivo. The unique odor of the leaves was analyzed by GC-MS. Lipid peroxidation, superoxide anion formation, and DPPH radicals were inhibited remarkably by the extracts of the leaves and roots. The leaves of this edible plant significantly protected the hepatotoxicity induced by carbon tetrachloride and further diminished the blood alcohol content in mice. While the roots of this plant exhibited adequate cytotoxicity against four human tumor cell lines, especially against melanoma, the leaves revealed relatively weak activity. Both the leaves and the roots exerted an excellent ameliorating property on scopolamine-induced memory impairment in the passive avoidance task using an animal model. The hexane fraction of the leaves was analyzed by GC-MS, suggesting that a series of terpenoids may be odorous compounds in this plant.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.27 no.4
• /
• pp.328-338
• /
• 2007

One of main advantages of composite using smart material as reinforcement can be controlled cracks behavior inside the composite. If the smart composite is applied as part of the structure, the use of the shape memory effect of the smart material is the best way to protect the propagation of cracks generated in the structure while use. In this study, the optical manufacturing conditions for the smart composite were derived. In order to evaluate the shape memory effect by shape memory alloy, the tensile load was applied to the smart composite and stress distribution was inspected. And then, the smart composite was heated to a certain temperature and the shape memory alloy would shrink to the original shape. Finally, at this point the recovering status of stress using photoelastic instrument was discussed.

• Korean Journal of Cognitive Science
• /
• v.18 no.2
• /
• pp.159-178
• /
• 2007

Lee & Kang (2002) showed that simultaneous phonological rehearsal significantly delayed the performance of multiplication but not subtraction, whereas holding an image in the memory delayed subtraction but not multiplication. This result indicated that arithmetic function is related to working memory in a subsystem-specific manner. The aim of the current study was to examine the neural correlates of previous finding using fMRI. For this goal, dual task conditions that required suppression or no suppression were manipulated. In general, several areas were more activated in the interference conditions than in the less interference conditions, although both conditions were dual condition. More important finding is that the specific areas activated in the phonological suppression rendition were right inferior frontal gyrus, left angular, and inferior parietal lobule, while the areas activated in the other condition were mainly in the right superior temporal gyrus and anterior cingulate gyrus. Furthermore, the areas activated in the phonological or visual less suppression condition were right medial frontal gyrus, left middle frontal gyrus, and bilateral medial frontal gyri, anterior cingulate cortices, and parahippocampal gyri, respectively. These results revealed that sharing the processing code invokes interference, and its neural basis.

• Journal of Korean Medicine Rehabilitation
• /
• v.18 no.4
• /
• pp.1-11
• /
• 2008

Objectives : Cerebral ischemia resulting from transient or permanent occlusion of cerebral arteries leads to neuronal cell death and eventually causes neurological impairments. Scrophulariae radix is the roots of Scrophularia buergeria. In the present study, we investigated the effects of the aqueous extract of Scrophulariae radix on apoptotic cell death in the hippocampal dentate gyrus following transient global ischemia in gerbils. Methods : For this study, step-down avoidance task, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay, and immunohistochemistry for caspase-3 were performed. Results : The present results showed that apoptotic cell death in the hippocampal dentate gyrus was significantly increased following transient global ischemia in gerbils. Treatment with the aqueous extract of Scrophulariae radix suppressed the ischemia-induced apoptosis in the dentate gyrus and thus facilitated the recovery of short-term memory impairment induced by ischemic cerebral injury. Conclusions : Here in this study, we have shown that Scrophulariae radix has a positive effect on-and possesses protective qualities against ischemia-induced apoptotic neuronal cell death, and it can be used for the treatment of ischemic brain diseases.