• Journal of Korean Ophthalmic Optics Society
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• v.7 no.2
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• pp.101-105
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• 2002

Spontaneous blinking as a function of visual activity and environmental condition with 60 healthy Korean young people(M=30, F=30) was estimated. Spontaneous blink rate of male and female was $19.2{\pm}2.0/min$ and $18.7{\pm}2.0/min$, respectively. There was no significant difference of blink rate in both contact lens wearer and non-wearer of female and also by various visual activity between female and male. Spontaneous blink rate was changed in response to changes in levels of visual activity and environmental condition such as windiness, rut not changed by light. In the more intense fixation spontaneous blink rate was lesser, but in the stronger windiness, the rate was higher than that in normal.

• International Journal of Internet, Broadcasting and Communication
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• v.6 no.2
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• pp.13-16
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• 2014

This study aims to examine the effects of watching 2D and 3D images on the blink rate. Regarding the image watch, their blink rate for 2D and 3D images was separately checked for 1 minute in the 1m distance, before the watch, after 15 minutes of watch, and after 30 minutes of watch. About the change of their blink rate in the 2D image watch, it tended to become higher than that before watching the image; however, there was no statistical significance (paired t-test, p=0.106, p=0.062). And in the 2D image watch, it tended to increase in comparison between after 15 minutes and after 30 minutes, but there was no statistical significance (paired t-test, p=0.623). Meanwhile, about the change of their blink rate in the 3D image watch, it tended to decrease statistically significantly both after 15 minutes and after 30 minutes when compared with that before watching the image (paired t-test, p=0.000, p=0.000). In the 3D image watch, it tended to increase in comparison between after 15 minutes and after 30 minutes; however, there was no statistical significance (paired t-test, p=0.867).

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.3
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• pp.173-179
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• 2006

We investigated the change of the blink rate by wearing soft contact lens(SCL). Eight types of soft contact lenses were worn by twelve asymptomatic contact lens wearers. When wearers were worn SCLs for 15 min, the average blink rate was 20.0 blinks/min, which was a statistically significant increase compared to 13.3 blinks/min, the average blink rate of non-SCL-worn eye. After 8 hr of lens wear, the average blink rate was 24.3 blinks/min, and it was 11 blinks/min more than that of non-SCL-worn eye and 4 blinks/min more than that of 15 min SCL-worn eye. There were a little difference of the blink rate in types of lens, which the blink rate range of all lens after 15 min of lens wear was 18.1~20.9 blinks/min and that after 8 hr of lens wear was 22.9~24.9 blinks/min. When wearing A lens(vifilcon, 0.06 mm) having thin center thickness, wearers showing difference of 10.0~11.9 blinks/min between non-SCL-worn eye and 15 min SCL-worn eye reached 16.7% and it was more than that of relatively thick B lens(0.17 mm) and C lens(0.14 mm). This result suggest that the center thickness was not unique factor of the blink rate change and other factors would have synthetically influence on the blink rate change. In the case of B lens and C lens of hilafilcon material but having different center thickness and water content, wearers increasing more than 4.0 blinks/min after 8 hr of lens wear was 58.3% and 41.7%, respectively. This result have provided information that the lenses of similar materials but different center thickness and water content could cause individually the different change of the blink rate.

• 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.

• Journal of Biomedical Engineering Research
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• v.18 no.4
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• pp.485-491
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• 1997

This paper describes the relationship between skin impedance signal, behavioral signal, and subjective evaluation depending on arousal level. Nz and reaction time had similar trend with mKSS level, but eyeblink rate was different from these two parameters. eye-blink rate increased slowly from mKSS level 1 to 5, and had high increasing rate at mKSS 7. But it showed steep descent at mKSS level 9. Each subject showed different eye-blink rates, but changing rates of EBR was similar at eachm KSS level. Therefore it suggests that rising rate of EBR can be used arousal level criterion. From the result of reaction time test. human performance was decreased rapidly above the mKSS level 5, and false positive and false negative data was observed above the mKSS level 3. It is desirable to give a subject some stimuli such as sound or aroma to rise arousal level between mKSS level 3 and mKSS level 5.

• Journal of Korean Ophthalmic Optics Society
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• v.14 no.2
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• pp.9-14
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• 2009

Purpose: The purpose of this study was to examine the relationship between the accommodative facility, blink rate and accommodative lag according to the change of angles of main viewpoint of near distance worker and study an appropriate viewing angle that mitigates asthenopia, such as headaches or eye fatigue accompanied when reading and staring at the computer or TV for a long time. Methods: Total of 27 people including 12 male university students and 15 female university students in the age of 20 to 36 with frequent near distance works, such as computers, were selected to study the accommodative facility, the blink rate and the accommodative lag in accordance with the change of viewing angles of the near distance workers. The refraction error was corrected completely and the phoropter was shifted to near distance mode to locate the near distance indication at 40 cm. The accommodative facility and the blink rate were measured for one minute at each viewing direction of $40^{\circ}$ downward, $20^{\circ}$ downward, horizontal, and $20^{\circ}$ upward directions based on the horizontal line and the accommodative lag was measured in dynamic retinoscopy using retinoscope. Results: As a result, when the main viewpoint was moved on upper direction from the $40^{\circ}$ below, the accommodative facility was reduced and the blink rate and the accommodative lag were increased so their eyes became dry and the accommodation response was reduced. Conclusions: In near distance works, the eye fatigue level can be minimized by locating a book or a computer screen $40^{\circ}$ below than the horizontal direction.

• Journal of Acupuncture Research
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• v.31 no.4
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• pp.121-131
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• 2014

Objectives : This study was performed to find the relation between prognosis of peripheral facial palsy and blink reflex. Methods : Data was collected from patients who were admitted and treated by East-West Collaborative Treatment of Facial Palsy Center in Kyung Hee University Hospital at Gangdong from January 2012 to June 2013. Patients were screened by inclusion/exclusion criteria and 163 patients' medical records were reviewed including blink reflex performed $14{\pm}2$ days after onset and House-Brackmann grade. Patients were divided into three groups, normal, delayed and absent group by blink reflex test. Trends of each recovery rate to House-Brackmann grade II and I depending on three group were analyzed at 1 month, 3 months and 6 months after onset using Linear by linear association. Results : At 1 month, 3 months and 6 months after onset, both recovery rate to House-Brackmann grade II and I had a tendency to be decreased statistically significantly in order of normal, delayed and absent group. Conclusions : We could find feasibility of blink reflex as a prognostic factor of peripheral facial palsy. Further study will be necessary.

• Journal of the Ergonomics Society of Korea
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• v.31 no.5
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• pp.609-616
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• 2012

Objective: The aim of the study is to evaluate the difference of legibility between e-book and paper-book by using eye-tracker. Background: Despite of many researches on the e-book and paper-book, there are few researches on the difference between e-book and paper-book. In addition, the researches on the e-book were only dependent on the e-book reader. This study focused on the comparison of e-book and paper-book controlled with the same environments. Method: This study was conducted with $2{\times}3$ within-subject design. Independent variables include the types of book (e-book, paper-book) and font sizes (8pt, 10pt, 12pt). Dependent variables are four measures of fixation duration, saccade length, blink rate and subjective discomfort. Analysis of Variance (ANOVA) with repeated measured design was used to investigate the main and interaction effects of independent variables on each of the dependent variables. The multiple comparisons were performed by post hoc analysis and Bonferroni correction was applied. Results: Fixation duration at e-book was longer than paper-book (p<0.01). Saccade length at e-book was shorter than paper-book (p<0.05). Blink rate at e-book was higher than paper-book (p<0.1). Subjective discomfort at e-book was higher than paper-book (p<0.1). Legibility at 8pt was better than 10pt, 12pt (p<0.01) in fixation duration, saccade length and subjective discomfort. Conclusion: It was found that the legibility at e-book are worse than paper-book from this study. These results indicated that the legibility of e-book was needed to be validated and improved to replace the paper-book. Application: This study suggests improving something related to fixation duration, saccade length, blink rate and subjective discomfort for betterment of e-book.

• The Journal of the Korea Contents Association
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• v.14 no.10
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• pp.463-471
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• 2014

In this paper, emotion classification was performed by using four ocular features extracted from near-infrared camera image. According to comparing with previous work, the proposed method used more ocular features and each feature was validated as significant one in terms of emotion classification. To minimize side effects on ocular features caused by using visual stimuli, auditory stimuli for causing two opposite emotion pairs such as "positive-negative" and "arousal-relaxation" were used. As four features for emotion classification, pupil size, pupil accommodation rate, blink frequency, and eye cloased duration were adopted which could be automatically extracted by using lab-made image processing software. At result, pupil accommodation rate and blink frequency were statistically significant features for classification arousal-relaxation. Also, eye closed duration was the most significant feature for classification positive-negative.

• Korean Journal of Biological Psychiatry
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• v.17 no.2
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• pp.79-85
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• 2010

Objectives : Trauma patients have attentional bias which enforces traumatic memories and causes cognitive errors. Understanding of such selective attention may explain many aspects of the posttraumatic stress disorder(PTSD) symptoms. Methods : We used the rapid serial visual presentation(RSVP) method to verify attentional blink in burn patients with PTSD. International affective picture system(IAPS) was used as stimuli and distracters. In the 'neutral test', patients have been presented series of pictures with human face picture as target stimuli. Each picture had 100ms interval. However the distance between target facial pictures was randomized and recognition of second facial picture accuracy was measured. In the 'stress test', the first target was stress picture which arouses patient emotions instead of the facial picture. Neutral and Stress tests were done with seven PTSD patients and 20 controls. In '85ms test' the interval was reduced to 85ms. The accuracy of recognition of second target facial picture was rated in all three tests. Eighty-five ms study was done with eighteen PTSD patients. Results : Attentional blinks were observed in 100-400ms of RSVP. PTSD patients showed increased recognition rate in the 'stress test' compared with the 'neutral test'. When presentation interval was decreased to 85 ms, PTSD patient showed decrease of attentional blink effect when target facial picture interval was 170ms. Conclusion : We found attentional blink effect could be affected by stress stimulus in burn patients. And attentional blink may be affected by stimulus interval and the character of stimulus. There may be some other specific mechanism related with selective attention in attentional blink especially with facial picture processing.