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Time-dependent Changes of Visual Acuity After Alcohol Ingestion (음주 후 시간경과에 따른 시력의 변화)

  • Kim, Sang-Yoeb;Lee, Sun Haeng;Moon, Byeong-Yeon;Yu, Dong-Sik;Cho, Hyun Gug
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.2
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    • pp.59-62
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    • 2008
  • Purpose: This study was designed to investigate the time-dependent changes of visual acuity after alcohol ingestion. Methods: Both the subjective and objective refraction, distant contrast sensitivity, and three needle tests were carried out at 1 and 3 hours after alcohol ingestion. Results: It was found that the degree of myoptization increased as the blood alcohol level increased in the range of average -0.25D ~ -0.35D when tested 1 and 3 hours after alcohol ingestion. Under the same test conditions the increase in blood alcohol resulted in the reduction in the function of dynamic stereopsis. However, the variation in contrast sensitivity was found to be insignificant for all spatial frequencies. Conclusions: The optician has to be well aware of the fact that alcohol could affect the visual acuity and functional tests, therefore inquiring of the alcohol ingestion prior to visual test can be necessary.

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The Investigation of the Relationship between Eye Blink and Visual Attention with Video Clip (영화클립을 이용한 눈깜빡임과 시각적 주의력과의 상관성 연구)

  • Kim, Sung Kyung;Kang, Min;Kang, Geon Ju;Park, Sujie;Shin, Young Seok;Jang, Dong Pyo
    • Journal of Biomedical Engineering Research
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    • v.35 no.4
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    • pp.99-104
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    • 2014
  • Generally, human eye blinks are closely associated with the cognitive state or visual attention such as attentional requirements on visual stimuli. These previous studies have reported that eye blinks are related to explicit visual attention using blink rate, pattern and blink timing across subjects. However, these results have been obtained in a well-controlled experimental settings. So, it would prove difficult to investigate human's natural response in a continuous and realistic situation. In our study, we measured the eye blink intervals while participants viewed a movie clip. And we analyzed the blink interval data for relationship between visual attention and eye blink intervals. 24 participants took part in two experimental sessions, first session to measure the IEBI while viewing the movie clip and second session to conduct a memory performance test using a self-questionnaire, which were spaced 3 weeks apart. The results indicate significantly higher memory performance at long IEBI period than short IEBI period while watching a movie clip(t = 3.257, df = 17, p < 0.005, 2-tailed). In addition, memory performance score significantly correlated with the IEBI value(spearman's rho = 0.40, N = 36, p < 0.01, 2-tailed). Our results suggest that IEBI is used to measure or assess visual attention while wiewing the movie that it is capable of simulating aspects of real-life experiences by visual attention. Thus, we expect IEBI to be used to measure or assess our visual attention, cognition, further emotion about not only movies, advertisements and other cultural contents but also cognitive science.

A Study on the Relationship of Space and Time in Visual Tactility (시각과 시촉각에 의한 운동 측면에서 본 공간과 시간의 관계성 연구 - 연경당 외부공간을 중심으로 -)

  • Yook, Ok-Soo
    • Journal of architectural history
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    • v.20 no.1
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    • pp.77-93
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    • 2011
  • Across the culture of Western Europe, dichotomy based on the visual sense has evolved. They believed eyes and ears requiring a distance related in recognition, are more developed than any other human senses in human body. Dominant position, as a condition to using a perspective, the eye has been just concentrated in the development of optical sight. But developed a variety of modern media, highlighting the importance of the other perception, it makes dichotomy to the expansion of perception over the single function of visuality. Recently, Guille Deleuze and Merleau-Ponty try to recover the sense of tactility segregated in skin from body keeping eyes for distance. By the result, the activity can be happened by being connected to the body rather than to eye in the space between the subject and object. From the phase of recognition where the human body tries to identify the object in the space considering a time, it will be changed for the subject to the phase of structure vice versa. Visual tactility is to eliminate the distance between subject and object. If the visual tactility is to erase the distance different from the visual in dichotomy, it will be occurred to having a tension and makes new relationship to work trying to move the subjective point of view in object. Like this evidence in analysis of architecture, it can be easy to find the Korean architecture rather than western architecture in terms of emphasizing the time and space. The fact, architecture of Lee Dynasty had been preserved and consisted basic form and style over the centuries makes us assume that visual tactility was considered as well as the visual sense. This study will be intensive in terms of visual and tactile inherent in the subject and how it is being connected to the movement in the space and time.

Analysis of learning effects using audio-visual manual of SWAT (SWAT의 시청각 매뉴얼을 통한 학습 효과 분석)

  • Lee, Ju-Yeong;Kim, Tea-Ho;Ryu, Ji-Chul;Kang, Hyun-Woo;Kum, Dong-Hyuk;Woo, Won-Hee;Jang, Chun-Hwa;Choi, Jong-Dae;Lim, Kyoung-Jae
    • Korean Journal of Agricultural Science
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    • v.38 no.4
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    • pp.731-737
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    • 2011
  • In the modern society, GIS-based decision support system has been used in evaluating environmental issues and changes due to spatial and temporal analysis capabilities of the GIS. However without proper manual of these systems, its desired goals could not be achieved. In this study, audio-visual SWAT tutorial system was developed to evaluate its effectives in learning the SWAT model. Learning effects was analyzed after in-class demonstration and survey. The survey was conducted for $3^{rd}$ grade students with/without audio-visual materials using 30 questionnaires, composed of 3 items for trend of respondent, 5 items for effects of audio-visual materials, and 12 items for effects of with/without manual in learning the model. For group without audio-visual manual, 2.98 out of 5 was obtained and 4.05 out of 5 was obtained for group with audio-visual manual, indicating higher content delivery with audio-visual learning effects. As shown in this study, the audio-visual learning material should be developed and used in various computer-based modeling system.

Comparison of Vertical and Horizontal Eye Movement Times in the Selection of Visual Targets by an Eye Input Device

  • Hong, Seung Kweon
    • Journal of the Ergonomics Society of Korea
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    • v.34 no.1
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    • pp.19-27
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    • 2015
  • Objective: The aim of this study is to investigate how well eye movement times in visual target selection tasks by an eye input device follows the typical Fitts' Law and to compare vertical and horizontal eye movement times. Background: Typically manual pointing provides excellent fit to the Fitts' Law model. However, when an eye input device is used for the visual target selection tasks, there were some debates on whether the eye movement times in can be described by the Fitts' Law. More empirical studies should be added to resolve these debates. This study is an empirical study for resolving this debate. On the other hand, many researchers reported the direction of movement in typical manual pointing has some effects on the movement times. The other question in this study is whether the direction of eye movement also affects the eye movement times. Method: A cursor movement times in visual target selection tasks by both input devices were collected. The layout of visual targets was set up by two types. Cursor starting position for vertical movement times were in the top of the monitor and visual targets were located in the bottom, while cursor starting positions for horizontal movement times were in the right of the monitor and visual targets were located in the left. Results: Although eye movement time was described by the Fitts' Law, the error rate was high and correlation was relatively low ($R^2=0.80$ for horizontal movements and $R^2=0.66$ for vertical movements), compared to those of manual movement. According to the movement direction, manual movement times were not significantly different, but eye movement times were significantly different. Conclusion: Eye movement times in the selection of visual targets by an eye-gaze input device could be described and predicted by the Fitts' Law. Eye movement times were significantly different according to the direction of eye movement. Application: The results of this study might help to understand eye movement times in visual target selection tasks by the eye input devices.

The Effect of Visual Bio-feedback Training on Balance and Postural Control in Stroke Patients (시지각 바이오피드백 훈련이 뇌졸중 환자의 균형 및 자세조절에 미치는 영향)

  • Lim, Soo-Jeong;Lee, Jong-Soo;Kim, Na-Ra;Kim, Seong-Sik;Lee, Byoung-Hee
    • Journal of Korean Medicine Rehabilitation
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    • v.21 no.1
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    • pp.137-148
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    • 2011
  • Objectives : This study was to investigate the visual bio-feedback training for 5 weeks on balance and postural control for patients with stroke. Methods : The 26 subjects were randomly selected from the patients of the E hospital in the S city who met the study conditions. They were divided into a visual bio-feedback training group of 13 patients and a self-resistance exercise group of 13 patients. The visual bio-feedback training group received visual bio-feedback and general physiotherapy for five weeks and the self-resistance exercise group received cycling and general physiotherapy for the same period. The subjects were measured and compared for stability index, weight distribution index, fall down index, functional reach test and timed up and go test before and after the program. Results : The visual bio-feedback training group showed significant changes after the experiment in stability index, weight distribution index, functional reach test and timed up and go test(p<0.05), and the self-resistance exercise group also showed significant differences(p<0.05). The changes between prior to and after the experiment show that the visual bio-feedback training group had more significant effects than the self-resistance exercise group(p<0.05). Conclusions : The visual bio-feedback training for five weeks had effects in the improvement of the balance and posture control of stroke patients. Based on these results, more effective training programs should be developed and propagated.

Effects of Visual Information Processing Skills on Intersection's Driving Performance of Elderly Drivers (고령 운전자의 시각 정보처리 능력이 교차로 운전수행에 미치는 영향)

  • Min, Yoon-Ki;Kim, Hyun-Woo;Lim, Dong-Hoon;Min, Byung-Chan;Kim, Bo-Seong
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.32 no.4
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    • pp.107-112
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    • 2009
  • The purpose of this study was to examine elderly drivers' driving performances at the intersections, suggested by Bao and Boyle(2009), according to visual information processing skills. Visual information processing skills of elderly drivers were measured by using the visual working memory task, developed by Min et al.(2006). Seven elderly drivers were divided into two groups(good/poor) depending on the level of visual information processing skills and eleven younger drivers were a contrast group. This study examined the differences of driving performance(i.e., intersection passing times, approach velocities, speed variation and handling variations) among three groups. The results showed that elderly drivers having the poor visual information processing skills passed more slowly through the intersection than the contrast group, and passing times between elderly drivers having the good visual information processing skills and the contrast group was not significantly different. It is suggested that elderly drivers having the poor visual information processing skills use more times when they pass through the intersection, because they don't process a lot of hazardous and latent hazardous factors quickly.

Study on Visual Recognition Enhancement of Yellow Carpet Placed at Near Pedestrian Crossing Areas : Visual Attention Software Implementation (횡단보도 옐로카펫 설치에 따른 시인성 증진효과 연구 : Visual Attention Software 분석 중심으로)

  • Ahn, Hyo-Sub;Kim, Jin-Tae
    • Journal of Information Technology Services
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    • v.15 no.4
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    • pp.73-83
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    • 2016
  • Pedestrian safety was recently highlighted with a yellow carpet, a yellow-colored pavement material prepared for children waiting for signals for pedestrian crossing, without validation of its efficiency in practice. It was a promising device likely to assist highway safety by stimulating pedestrian to step on the yellow-colored area; it was generally called nudge effects. This paper delivers a study conducted to check the effectiveness of yellow carpet in three different aspects in vehicle driver's perspective by applying the newly introduced information technology (IT) service: Visual Attention Software (VAS). It was assumed that VAS developed by 3M in the United States should be able explain the Korean drivers' visual reaction behaviors since technology embedded in VAS was developed based on and proved by other various international countries and continents in the world. A set of pictures was taken at thirteen different field sites in seven school zone areas in the Seoul metropolitan area before and after the installation of a yellow carpet, respectively. Sets of those pictures were analyzed with VAS, and the results were compared based on the selective safety measures: the likely focusing on standing pedestrians (waiting for a pedestrian's green signal time) affected by its background (yellow-colored pavement) contrasting him or her. The test results from a set of before-and-after comparison analyses showed that the placement of yellow carpet would (1) increase 71% of driver's visual attention on pedestrian crossing areas and (2) change the sequential order of visual attention on that area 2.4 steps ahead. The findings would enhance deployment of such promising efficiency and thus increase children safety in pedestrian crossing. The result was promising to highlight the way to support the changes in conservative traffic safety engineering field by applying the advanced IT services, while much robust research was recommended to overcome the limitation of simplification of this study.

Visual Outcome after Surgical Removal of Craniopharyngiomas

  • Kim, Yeon-Seong;Jung, Shin;Cheon, Hyo-Cheol;Jung, Tae-Young;Kang, Sam-Suk;Kim, Soo-Han
    • Journal of Korean Neurosurgical Society
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    • v.39 no.3
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    • pp.171-175
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    • 2006
  • Objective : In the present study, we evaluate visual outcomes after surgical removal of craniopharyngiomas and analyze the factors that are considered to affect visual outcomes. Methods : This study includes 30 patients with craniopharyngioma, who underwent surgery in this clinic during the last 10 years. The changes of visual function [visual acuity and field] of the patients were assessed preoperatively and postoperatively, and paired data of this change were compared. Also, the factors that influence on this change were analysed. Results : Among the 21 patients complaining of decreased vision before the operation, 8 patients were improved [38.0%], and 7 patients were worse [33.3%]. However, Four out of 9 patients without any preoperative visual symptoms developed worse vision after the operation [44.4%]. The average duration of symptom was 17.2 months in the improved group and 23.6 months in the aggravated group. The tumors recurred in only 5 patients after the gross total resection : Four of them showed the aggravation of visual function after surgical removal and 1 had improvement. Conclusion : After removal of craniopharyngiomas, the overall rate of vision improvement, no change and aggravation are 26.6%, 36.7% and 36.7%, respectively. Aggravation of postoperative visual function is higher in males, children and patients with a longer duration of symptom and the tumor recurres more frequently in patients who complained of worsened vision after surgical removal.

Eye Movement Program Consisting of Saccadic Eye Movement and Pursuit Eye Movement Improved Visual Memory in Institutionalized Elderly Person: Randomized controlled pilot study

  • Park, Yongnam;Bae, Youngsook
    • Journal of International Academy of Physical Therapy Research
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    • v.10 no.2
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    • pp.1768-1773
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    • 2019
  • Background: Aging reduces cognitive abilities, including visual memory (VM) and visual discrimination (VD). Since common cortical networks subserve eye movement and attention, voluntary eye movement may improve visual attention. Visual selective attention was major role for memory, and visual memory and visual attention are intimately related. Objective: To identify the improvement in VD and VM, after implementing the eye movement program consisting of saccadic eye movement (SEM) and pursuit eye movement (PEM) in the institutionalized healthy elderly. Design: Randomized controlled trial. Methods: The study involved a sample of 36 participants, and the mean age was 79.03 years (range 76~84 years). They were randomly allocated to the experimental group (n=16) and control group (n=20). Participants in the experimental group performed SEM 5 times per week for 4 weeks: twice daily at the same time in the morning and afternoon. The program was carried out for 3 minutes, and it consisted of SEM and PEM. The target's moving frequency was set at 0.5 Hz. VM and VD at the baseline and post-intervention were measured using Motor-Free Visual Perception test-4 (MFVPT-4). Results: VM significantly improved in the experimental group (p < .01), and significant differences were observed compared to the control group (p < .01). There was no significant change in VD. Conclusion: The eye movement program consisting of SEM and PEM increased VM more than VD. Therefore, eye movement program was feasible interventions for improving VM in institutionalized elderly persons.