• Korean Journal of Cognitive Science
• /
• v.27 no.2
• /
• pp.159-219
• /
• 2016

Mathematical ability is important for academic achievement and technological renovations in the STEM disciplines. This study concentrated on the relationship between neural basis of mathematical cognition and its mechanisms. These cognitive functions include domain specific abilities such as numerical skills and visuospatial abilities, as well as domain general abilities which include language, long term memory, and working memory capacity. Individuals can perform higher cognitive functions such as abstract thinking and reasoning based on these basic cognitive functions. The next topic covered in this study is about individual differences in mathematical abilities. Neural efficiency theory was incorporated in this study to view mathematical talent. According to the theory, a person with mathematical talent uses his or her brain more efficiently than the effortful endeavour of the average human being. Mathematically gifted students show different brain activities when compared to average students. Interhemispheric and intrahemispheric connectivities are enhanced in those students, particularly in the right brain along fronto-parietal longitudinal fasciculus. The third topic deals with growth and development in mathematical capacity. As individuals mature, practice mathematical skills, and gain knowledge, such changes are reflected in cortical activation, which include changes in the activation level, redistribution, and reorganization in the supporting cortex. Among these, reorganization can be related to neural plasticity. Neural plasticity was observed in professional mathematicians and children with mathematical learning disabilities. Last topic is about mathematical creativity viewed from Neural Darwinism. When the brain is faced with a novel problem, it needs to collect all of the necessary concepts(knowledge) from long term memory, make multitudes of connections, and test which ones have the highest probability in helping solve the unusual problem. Having followed the above brain modifying steps, once the brain finally finds the correct response to the novel problem, the final response comes as a form of inspiration. For a novice, the first step of acquisition of knowledge structure is the most important. However, as expertise increases, the latter two stages of making connections and selection become more important.

• Korean Journal of Cognitive Science
• /
• v.27 no.4
• /
• pp.573-597
• /
• 2016

Recent fMRI and EEG research for neural representations of action concepts insist that processing of action concepts evoke the simulation of sensory-motor information. Moreover, there are several behavioral studies showing that understanding of action verbs or sentences describing actions interfere or facilitate current action performance. However, it is unclear that online interaction between processing of action concepts and current action is based on the simulation of sensory-motor information, or other neural mechanisms. The present research aims to explore the underlying neural mechanism that how the perception of action language influence the performance of current action using high-spacial temporal resolution EEG and multiple source analysis techniques. For this, participants were asked to perform a cued-motor reaction task in which button-pressing hand action and pedal-stepping foot action were required according to the color of the cue, and we presented auditorily action verbs describing the responding actions (i.e., /press/, /step/, /stop/) just before the color cue and examined the interaction effect from the semantic congruency between the action verbs and the current action. Behavioral results revealed consistently a facilitatory effect when action verbs and responding actions were semantically congruent in both button-pressing and pedal-stepping actions, and an inhibitory effect when semantically incongruent in the button-pressing action condition. In the results of EEG source waveform analysis, the semantic congruency effects between action verbs and the responding actions were observed in the Wernicke's area during the perception of action verbs, in the anterior cingulate gyrus and the supplementary motor area (SMA) at the time when the motor-cue was presented, and in the SMA and primary motor cortex (M1) during action execution stage. Based on the current findings, we argue that perceived action verbs evoke the facilitation/inhibition effect by influencing the expectation and preparation stage of following actions rather than the directly activating the particular motor cortex. Finally we discussed the implication on the neural representation of action concepts and methodological limitations of the current research.

• Korean Journal of Cognitive Science
• /
• v.23 no.2
• /
• pp.225-248
• /
• 2012

The summed-similarity model of visual short-term recognition proposes that the estimated amount of summed similarity between remembered items and a recognition probe determines recognition judgement decision (Kahan & Sekuler, 2002). This study examined the effect of a task-irrelevant location change on the recognition decision against two remembered Gabor gratings differing in their spatial frequencies. On each trial in Experiment, participants reported if two gratings displayed across the visual fields are the same or not as the probe grating displayed after about a second of memory delay. The probe grating would be the same as or different from the memory items (lure) by 1 or 4 JND units. The location of the probe would also vary randomly across the left and right visual field with respect to the location of the corresponding memory item. The participants were instructed to perform their recognition task exclusively to the spatial frequencies of the memory items and the probe while ignoring the potential location change of the probe. The results showed that false-recognition rates of the lure probe increased as the summed similarity between the memory items and the probe increased. The rates also further increased in the condition where the probe location was different from the location of the corresponding memory item compared to the condition where the probe location was the same. The increased false-recognition rates indicate that information stored into visual short-term memory is represented as a form of well-bound visual features rather than independent features.

• Journal of Korean Academy of Nursing
• /
• v.27 no.4
• /
• pp.807-819
• /
• 1997

The purpose of the study was to identify the effects of a 12-week low-intensity exercise program on muscle strength, flexibility, balance, and cognitive characteristics related to the performance of activity of daily living(ADL). A total of 16 patients who were admitted to the medical unit of a general hospital in ChoongChung province were recruited, eight for the exercise group and eight for the comparison group. Four levels of low-intensity exercise from 'ROM on bed' to 'exercise while walking' were then applied to the exercise group according to their physical condition. During hospitalization, patients in the exercise group performed each level of the prescribed exercise with the researchers until they felt comfortable doing it independently. The researchers also visited the patients' homes after discharge to make sure they could perform the exercise with Theraband in their living environment. The exercise group was contacted by phone once a week to assess the frequency and intensity in which they performed the exercise as well as their physical condition. The subjects in the comparison group participated in measurements for the study without performing the exercise and were contacted by phone after discharge, in a matched time frame with the exercise group, to assess physical condition. Muscle strength, flexibility, balance, cognitive characteristics, and performance of ADL for the two groups were compared at the pretest and the posttest after the low-intensity exercise program by utilizing SPSSWIN and the results are as follows : 1) At the postest, measurements of muscle strengths showed that the strength of the dorsal flexor in the exercise group was significantly higher than in the comparison group. 2) Objective balance for the exercise group was significantly better than for the comparison group as measured by 'standing on one foot' and Tinetti gait and balance control. 3) The exercise group showed significantly higher task self-efficacy than the comparison group. 4) Perceived exertion for ADL for the exercise group was significantly lower than for the comparison group. 5) Improvement of performance of ADL without assistance was significantly higher for the exercise group than the comparison group. The findings suggest that a low-intensity exercise program would be useful for the elderly who show decline in their physical functioning due to hospitalization by partly improving physical strength, task self-efficacy, and performance of ADL. Directions for further research on issues of motivating people to exercise as well as of standardizing various types of exercise were discussed.

• Korean Journal of Cognitive Science
• /
• v.28 no.4
• /
• pp.329-347
• /
• 2017

Early research into category-based feature inference reported various phenomena in human thinking including typicality, diversity, similarity effects, etc. Later research discovered that participants' prior knowledge has an extensive influence on these sorts of reasoning. The current research tested the effects of causal knowledge on feature inference and conducted modeling on the results. Participants performed feature inference for categories consisted of four features where the features were connected either in common cause or common effect structure. The results showed typicality effects along with violations of causal Markov condition in common cause structure and causal discounting in common effect structure. To model the results, it was assumed that participants perform feature inference based on the difference between the probabilities of an exemplar with the target feature and an exemplar without the target feature (that is, $p(E_{F(X)}{\mid}Cat)-p(E_{F({\sim}X)}{\mid}Cat)$). Exemplar probabilities were computed based on causal model theory (Rehder, 2003) and applied to inference for target features. The results showed that the model predicts not only typicality effects but also violations of causal Markov condition and causal discounting observed in participants' data.

• Science of Emotion and Sensibility
• /
• v.12 no.4
• /
• pp.373-380
• /
• 2009

This study tried to investigate how three levels of arousal affect performance of a 3-back task. Ten university male (age $25.7{\pm}1.5$) and ten female (age $24.5{\pm}1.8$) students participated in this experiment. Using pictures selected from a group test, three levels of arousal, i.e. tensed, neutral, and relaxed emotions, were induced. Each subject was run through the procedure three times, once for each arousal level. The procedure consisted of six phases for each arousal condition Rest 1(2 min), Picture 1(presenting emotion arousing photos for 2 min), 3-back task 1(2 min), Picture 2(presenting emotion arousing photos for 2 min), 3-back task 2(2 min), and Rest 2(2 min). Skin conductance level(SCL) of electrothermal activity was also measured during all phases of the experiment. The accuracy rate of 3-back task performance was the highest at a neutral emotional state, followed by relaxed and then tensed emotional state. There was no difference in reaction time(RT) among the three levels of arousal. SCL was the highest at a tensed emotional state, followed by neutral emotional state and then relaxed emotional state. Based on the results, it could be inferred that tension, induced by stimuli unrelated to cognitive tasks, decreases the ability to perform cognitive tasks.

• Korean Journal of Cognitive Science
• /
• v.23 no.4
• /
• pp.425-455
• /
• 2012

Multi-dimensional verbal short-term memory mechanisms are largely divided into the phonological channel and the lexical-semantic channel. The former is called phonological short-term memory and the latter is called semantic short-term memory. Phonological short-term memory is further segmented into the phonological input buffer and the phonological output buffer. In this study, the language performance of each of three patients with similar levels of conduction aphasia was analyzed in terms of multi-dimensional verbal short-term memory. To this end, three patients with conduction aphasia were instructed to perform four different aspects of language tasks that are spontaneous speaking, repetition, spontaneous writing, and dictation in both word and sentence level. Moreover, the patients' phonological memories and semantic short-term memories were evaluated using digit span tests and verbal learning tests. As a result, the three subjects exhibited various types of performances and error responses in the four aspects of language tests, and the short-term memory tests also did not produce identical results. The language performance of three patients with conduction aphasia can be explained according to whether the defects occurred in the semantic short-term memory, phonological input buffer and/or phonological output buffer. In this study, the relations between language and multi-dimensional verbal short-term memory were discussed based on the results of language tests and short-term memory tests in patients with conduction aphasia.

• Korean Journal of Cognitive Science
• /
• v.18 no.2
• /
• pp.193-221
• /
• 2007

This study explored the efficient hierarchical data structure of mobile interfaces. The first experiment demonstrated the effects of grouping(clear/unclear), depth level(2/3/5), and the number of items(32/64/128) on the search time and the number of errors. The results indicated that participants spent less time and made fewer errors to perform the task when the clear mobile interfaces, low depth level, and fewer items were provided. In addition, the results indicated that there were no effects of the depth level and the number of items on the search time and number of errors in clear mobile interfaces conditions. As depth level and the number of items changed, on the other hand, participants spent longer time to complete the task and made more mistakes in unclear mobile interfaces conditions. The second experiment investigated the effects of grouping(clear/unclear), the number of items(32/64/128), and spacial cues(colors/ windows/ number of cues) on search time and the number of errors in hierarchical data structures which had five depth levels. The results indicated that participants spent less time to complete the task and made less errors in a mobile interface when grouping is clear and the number of items are fewer. The results were identical with the first experiments. In addition, the main effect of spacial cues indicated that providing spacial cues via pictures and numbers can be helpful to reduce errors in search behaviors.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.5
• /
• pp.428-435
• /
• 2017

The purpose of this study is to propose a health improvement education program for the majority of elderly people who could not work due to health issues. This study focused on the fact that employment has a positive influence on the health outcomes of the elderly. The paper compares the health outcomes of employed elderly versus that of the unemployed, and suggests directions for future lifelong education programs related to health for the unemployed elders. The study results show more positive health outcomes for employed elders in terms of nutrition status and ability to perform daily tasks. Furthermore, their cognitive ability was more active (orientation, peripheral concentration, awareness of daily life) and their overall quality of life. Therefore, the study aims to develop health outcomes in the unemployed elderly population through safety education, improving health habits, performance improvement education via cognitive activation and socializing, and to secure the professionalism of lifelong education programs for the elderly which is currently only seen as a leisure activity. The object of the proposed program in this study is to maintain health by providing opportunities employment - a core component of successful aging - and relevant social interaction. This will greatly improve the quality of life of the elderly and provide a basis for widening the social role of elderly people in the future.

• Korean Journal of Cognitive Science
• /
• v.9 no.1
• /
• pp.31-39
• /
• 1998

This paper describes an electronic performance support system called HELPS(Handler Electronic Learning Performence Support) for semiconductor testing e equipment. The purpose of this system is to improve productivity of operators by providing just-in-time, on-the-job, mutimedia-based system information for operational support, training, and knowledge-based trouble shooting and repair. HELPS is composed of a operation module and a trouble shooting module. The operation module uses multimedia and hypermedia to provide the detailed and easily accessible information about equipment to users. Multimedia incorporate multiple. media forms including still and video images. animations 'texts' graphics. and audio. Hypermedia a are provided through a hierarchical information structure which offers not only specific information which is needed to perform a task to experienced operators. but detailed system guidance and information to novice operators. The trouble shooting module is composed of an integrated mutimedia-supported expert system which assists operators in trouble shooting and equipment repair. After diagnosis through the use of the expert system. multimedia advice is presented to the user in either still images with text or motion sequences with sound HELPS is evaluated in term of training time and trouble shooting and repair time. It improved productivity by saving more than 30% of the total time used without the system. This s system has the potential to improve productivity when it is used with ICAIOntellignet Computer Aided Instruction) and virtual reality.