Master

• Faculty of Engineering　Division of Environmental Engineering　Division of Environmental Engineering

• Faculty of Engineering　Division of Environmental Engineering　Division of Environmental Engineering

Profile and Settings

• Name (Japanese)

  Sang-il

• Name (Kana)

  Lee

• Name

  201701004896990000

http://www.eng.hokudai.ac.jp/labo/EN-ERGO/

Achievement

• Living environment   Light Environment   Chronobiology   Physiological Anthropology   Environmental Ergonomics   

• Life sciences / Nutrition and health science
• Humanities & social sciences / Home economics, lifestyle science
• Life sciences / Applied anthropology

• 2017/12 - Today Hokkaido University Faculty of Engineering Assistant Professor
• 2016/04 - 2017/11 Kyushu University Faculty of Design Research Assistant Professor
• 2014/04 - 2016/03 Kyushu University Faculty of Design Academic researcher

• 2024/06 The 20th International Conference on Environmental Ergonomics First Place in the Poster Presentation Award
   Estimation of Thermal Environment Index Based on Clothing Type Identification Using Image Recognition Technology 

  受賞者: Koichi Ishii;Biplob Kanti Biswas;Yu Watanabe;Ayano Dempoya;Jiating Li;Yumiko Tan;Sang-il Lee;Takuji Iwamura;Shingo Konoshita;Hitoshi Wakabayashi
• 2023/09 日本時間生物学会（第３０回日本時間生物学会学術大会） 優秀演題賞
   外界の明暗変化の視覚的情報がヒトの時間認知に与える影響 

  受賞者: 丹由美子;李佳テイ;坂彌輔竜;李スミン;若林斉;李相逸
• 2021/10 日本生理人類学会第81回大会 優秀発表賞
   照明の色温度と壁の配色の組み合わせがヒトの瞳孔の対光反射に与える影響 

  受賞者: 佐藤信吾;桶谷康祐;李相逸;李スミン;濱田靖弘
• 2019/03 ICPA 2019 - The 14th International Congress of Physiological Anthropology Best Poster Award (1st Prize)
   EFFECT OF L-SERINE INTAKE BEFORE BEDTIME ON PHASE OF CIRCADIAN RHYTHM: A FIELD STUDY 

  受賞者: Michihiro Ohashi;Taisuke Eto;Sang-il Lee;Chie Tarumizu;Sayuri Matsuoka;Shinobu Yasuo;Shigekazu Higuchi
• 2016/07 日本睡眠学会 日本睡眠学会第41回定期学術集会ベストプレゼンテーション賞
   

  受賞者: 李 相逸
• 2014/06 日本生理人類学会 日本生理人類学会奨励賞
   

  受賞者: 李 相逸
• 2013/10 日本生理人類学会 日本生理人類学会第68回大会優秀発表賞
   

  受賞者: 李 相逸
• 2012/09 日本時間生物学会 日本時間生物学会第19回大会優秀ポスター賞
   

  受賞者: 李 相逸

• Circadian phase advances in children during camping life according to the natural light-dark cycle

  Taisuke Eto, Shingo Kitamura, Kana Nishimura, Kota Takeoka, Yuki Nishimura, Sang-il Lee, Michihiro Ohashi, Akiko Shikano, Shingo Noi, Shigekazu Higuchi

  Journal of Physiological Anthropology 41 (1) 2022/12/16 

  Abstract Background It is known that the circadian rhythm phase in adults can be advanced in a natural light-dark cycle without electrical lighting. However, the effect of advanced sleep-wake timing according to the natural light-dark cycle on children’s circadian phase is unclear. We investigated the effects of approximately 2 weeks of camping life with little access to artificial lighting on children’s circadian phases. We also conducted an exploratory examination on the effects of wake time according to natural sunrise time on the manner of the advance of their circadian phases. Methods Twenty-one healthy children (mean ± SD age, 10.6 ± 1.4 years) participated in a camping program with wake time (4:00) being earlier than sunrise time (EW condition), and 21 healthy children (10.4 ± 1.1 years) participated in a camping program with wake time (5:00) being almost matched to sunrise time (SW condition). Salivary dim light melatonin onset (DLMO) before the camping program and that after approximately 2 weeks of camping were compared. Results DLMO was advanced by approximately 2 h after the camping program compared with the circadian phase in daily life in both conditions. In addition, the advances in DLMO were significantly correlated with mid-sleep points before the camp in both conditions (EW: r = 0.72, p < 0.01, SW: r = 0.70, p < 0.01). These correlations mean that the phase advance was greater for the children with delayed sleep habits in daily life. Furthermore, in the EW condition, mean DLMO after the camp (18:09 ± 0:33 h) was earlier than natural sunset time and there was no significant decrease in interindividual variability in DLMO. On the other hand, in the SW condition, mean DLMO after the camp (18:43 ± 0:20 h) matched natural sunset time and interindividual variability in DLMO was significantly lower than that before the camp. Conclusions Camping with advanced sleep and wake timing under natural sunlight advances children’s circadian phases. However, DLMO earlier than sunset in an early waking condition may lead to large interindividual variability in the circadian rhythm phase.

  Abstract Background It is known that the circadian rhythm phase in adults can be advanced in a n......See More

  ×Abstract Background It is known that the circadian rhythm phase in adults can be advanced in a natural light-dark cycle without electrical lighting. However, the effect of advanced sleep-wake timing according to the natural light-dark cycle on children’s circadian phase is unclear. We investigated the effects of approximately 2 weeks of camping life with little access to artificial lighting on children’s circadian phases. We also conducted an exploratory examination on the effects of wake time according to natural sunrise time on the manner of the advance of their circadian phases. Methods Twenty-one healthy children (mean ± SD age, 10.6 ± 1.4 years) participated in a camping program with wake time (4:00) being earlier than sunrise time (EW condition), and 21 healthy children (10.4 ± 1.1 years) participated in a camping program with wake time (5:00) being almost matched to sunrise time (SW condition). Salivary dim light melatonin onset (DLMO) before the camping program and that after approximately 2 weeks of camping were compared. Results DLMO was advanced by approximately 2 h after the camping program compared with the circadian phase in daily life in both conditions. In addition, the advances in DLMO were significantly correlated with mid-sleep points before the camp in both conditions (EW: r = 0.72, p < 0.01, SW: r = 0.70, p < 0.01). These correlations mean that the phase advance was greater for the children with delayed sleep habits in daily life. Furthermore, in the EW condition, mean DLMO after the camp (18:09 ± 0:33 h) was earlier than natural sunset time and there was no significant decrease in interindividual variability in DLMO. On the other hand, in the SW condition, mean DLMO after the camp (18:43 ± 0:20 h) matched natural sunset time and interindividual variability in DLMO was significantly lower than that before the camp. Conclusions Camping with advanced sleep and wake timing under natural sunlight advances children’s circadian phases. However, DLMO earlier than sunset in an early waking condition may lead to large interindividual variability in the circadian rhythm phase.
• Intake of l-serine before bedtime prevents the delay of the circadian phase in real life

  Michihiro Ohashi, Sang-il Lee, Taisuke Eto, Nobuo Uotsu, Chie Tarumizu, Sayuri Matsuoka, Shinobu Yasuo, Shigekazu Higuchi

  Journal of Physiological Anthropology 41 (1) 2022/08/26 [Refereed][Not invited]
   

  Abstract Background It has been shown in laboratory experiments using human subjects that ingestion of the non-essential amino acid l-serine before bedtime enhances the advance of circadian phase induced by light exposure the next morning. In the present study, we tested the effect of ingestion of l-serine before bedtime on circadian phase in real life and whether its effect depends on the initial circadian phase. Methods The subjects were 33 healthy male and female university students and they were divided into an l-serine group (n = 16) and a placebo group (n = 17). This study was conducted in a double-blind manner in autumn and winter. After a baseline period for 1 week, the subjects took 3.0 g of l-serine or a placebo 30 min before bedtime for 2 weeks. Saliva was collected twice a week at home every hour under a dim light condition from 20:00 to 1 h after habitual bedtime. Dim light melatonin onset (DLMO) was used as an index of phase of the circadian rhythm. Results DLMO after intervention was significantly delayed compared to the baseline DLMO in the placebo group (p = 0.02) but not in the l-serine group. There was a significant difference in the amount of changes in DLMO between the two groups (p = 0.04). There were no significant changes in sleeping habits after intervention in the two groups. There were significant positive correlations between advance of DLMO and DLMO before intervention in the l-serine group (r = 0.53, p < 0.05) and the placebo group (r = 0.69, p < 0.01). There was no significant difference in the slopes of regression lines between the two groups (p = 0.71), but the intercept in the l-serine group was significantly higher than that in the placebo group (p < 0.01). The levels of light exposure were not significantly different between the two groups. Conclusions Our findings suggest that intake of l-serine before bedtime for multiple days might attenuate the circadian phase delay in the real world and that this effect does not depend on the initial circadian phase. Trial registration This study is registered with University Hospital Medical Information Network in Japan (UMIN000024435. Registered on October 17, 2016).

  Abstract Background It has been shown in laboratory experiments using human subjects that ingest......See More

  ×Abstract Background It has been shown in laboratory experiments using human subjects that ingestion of the non-essential amino acid l-serine before bedtime enhances the advance of circadian phase induced by light exposure the next morning. In the present study, we tested the effect of ingestion of l-serine before bedtime on circadian phase in real life and whether its effect depends on the initial circadian phase. Methods The subjects were 33 healthy male and female university students and they were divided into an l-serine group (n = 16) and a placebo group (n = 17). This study was conducted in a double-blind manner in autumn and winter. After a baseline period for 1 week, the subjects took 3.0 g of l-serine or a placebo 30 min before bedtime for 2 weeks. Saliva was collected twice a week at home every hour under a dim light condition from 20:00 to 1 h after habitual bedtime. Dim light melatonin onset (DLMO) was used as an index of phase of the circadian rhythm. Results DLMO after intervention was significantly delayed compared to the baseline DLMO in the placebo group (p = 0.02) but not in the l-serine group. There was a significant difference in the amount of changes in DLMO between the two groups (p = 0.04). There were no significant changes in sleeping habits after intervention in the two groups. There were significant positive correlations between advance of DLMO and DLMO before intervention in the l-serine group (r = 0.53, p < 0.05) and the placebo group (r = 0.69, p < 0.01). There was no significant difference in the slopes of regression lines between the two groups (p = 0.71), but the intercept in the l-serine group was significantly higher than that in the placebo group (p < 0.01). The levels of light exposure were not significantly different between the two groups. Conclusions Our findings suggest that intake of l-serine before bedtime for multiple days might attenuate the circadian phase delay in the real world and that this effect does not depend on the initial circadian phase. Trial registration This study is registered with University Hospital Medical Information Network in Japan (UMIN000024435. Registered on October 17, 2016).
• 光環境の変化が一晩の模擬的夜勤時の概日リズムの位相に及ぼす影響

  高巣 とあ希, 大橋 路弘, 江藤 太亮, 境 吾見, 李 相逸, 元村 祐貴, 樋口 重和

  日本睡眠学会定期学術集会プログラム・抄録集 (一社)日本睡眠学会 47回 253 - 253 2022/06
• Effects of 2-hour nighttime nap on melatonin concentration and alertness during 12-hour simulated night work

  Sang-il LEE, Takeshi NISHI, Masaya TAKAHASHI, Shigekazu HIGUCHI

  Industrial Health 59 (6) 393 - 402 0019-8366 2021/11/30 [Refereed]
   

  A nighttime nap is expected to mitigate melatonin suppression during night work by blocking light input to the retina, but it is unclear. In the present study, we investigated the effects of a nap break on melatonin level, subjective sleepiness, and vigilance performance during simulated night work. Eleven healthy young males (mean ± SD age: 22.2 ± 4.1 years) participated in counterbalanced crossover design experiments with two conditions (nap vs. no nap). The subjects performed 12-hour simulated night work from 21:00 to 09:00 h (illuminance: ~500 lx). Subjects with a nap condition took a nap for 2 hours in a dark room from 03:00, while subjects with a no nap condition continued the simulated night work. The results showed that immediately after the 2-h nap break, the melatonin level at 05:00 h temporarily recovered from light-induced melatonin suppression during the simulated night work but significantly suppressed again at 07:00 and 09:00 h. Subjective alertness and vigilance performance were impaired immediately after the nap break but subsequently enhanced. The results suggest that a single nap break for 2 hours could be a strategy to enhance alertness during the last part of night shift but inadequate for mitigating melatonin suppression.

  A nighttime nap is expected to mitigate melatonin suppression during night work by blocking light in......See More

  ×A nighttime nap is expected to mitigate melatonin suppression during night work by blocking light input to the retina, but it is unclear. In the present study, we investigated the effects of a nap break on melatonin level, subjective sleepiness, and vigilance performance during simulated night work. Eleven healthy young males (mean ± SD age: 22.2 ± 4.1 years) participated in counterbalanced crossover design experiments with two conditions (nap vs. no nap). The subjects performed 12-hour simulated night work from 21:00 to 09:00 h (illuminance: ~500 lx). Subjects with a nap condition took a nap for 2 hours in a dark room from 03:00, while subjects with a no nap condition continued the simulated night work. The results showed that immediately after the 2-h nap break, the melatonin level at 05:00 h temporarily recovered from light-induced melatonin suppression during the simulated night work but significantly suppressed again at 07:00 and 09:00 h. Subjective alertness and vigilance performance were impaired immediately after the nap break but subsequently enhanced. The results suggest that a single nap break for 2 hours could be a strategy to enhance alertness during the last part of night shift but inadequate for mitigating melatonin suppression.
• Diurnal variations of brown fat thermogenesis and fat oxidation in humans

  Mami Matsushita, Shinsuke Nirengi, Masanobu Hibi, Hitoshi Wakabayashi, Sang-il Lee, Masayuki Domichi, Naoki Sakane, Masayuki Saito

  International Journal of Obesity 0307-0565 2021/08/02 

  Disturbed circadian rhythm is associated with an increased risk of obesity and metabolic disorders. Brown adipose tissue (BAT) is a site of nonshivering thermogenesis (NST) and plays a role in regulating whole-body energy expenditure (EE), substrate metabolism, and body fatness. In this study, we examined diurnal variations of NST in healthy humans by focusing on their relation to BAT activity. Forty-four healthy men underwent ¹⁸F-fluoro-2-deoxy-D-glucose positron emission tomography and were divided into Low-BAT and High-BAT groups. In STUDY 1, EE, diet-induced thermogenesis (DIT), and fat oxidation (FO) were measured using a whole-room indirect calorimeter at 27 °C. In STUDY 2, EE, FO, and skin temperature in the region close to BAT depots (Tscv) and in the control region (Tc) were measured at 27 °C and after 90 min cold exposure at 19 °C in the morning and in the evening. In STUDY 1, DIT and FO after breakfast was higher in the High-BAT group than in the Low-BAT group (P < 0.05), whereas those after dinner were comparable in the two groups. FO in the High-BAT group was higher after breakfast than after dinner (P < 0.01). In STUDY 2, cold-induced increases in EE (CIT), FO, and Tscv relative to Tc in the morning were higher in the High-BAT group than in the Low-BAT group (P < 0.05), whereas those after dinner were comparable in the two groups. CIT in the High-BAT group tended to be higher in the morning than in the evening (P = 0.056). BAT-associated NST and FO were evident in the morning, but not in the evening, suggesting that the activity of human BAT is higher in the morning than in the evening, and thus may be involved in the association of an eating habit of breakfast skipping with obesity and related metabolic disorders.

  Abstract Background/objectives Disturbed circadian rhythm is associated with an increased risk of ......See More

  × Disturbed circadian rhythm is associated with an increased risk of obesity and metabolic disorders. Brown adipose tissue (BAT) is a site of nonshivering thermogenesis (NST) and plays a role in regulating whole-body energy expenditure (EE), substrate metabolism, and body fatness. In this study, we examined diurnal variations of NST in healthy humans by focusing on their relation to BAT activity. Forty-four healthy men underwent ¹⁸F-fluoro-2-deoxy-D-glucose positron emission tomography and were divided into Low-BAT and High-BAT groups. In STUDY 1, EE, diet-induced thermogenesis (DIT), and fat oxidation (FO) were measured using a whole-room indirect calorimeter at 27 °C. In STUDY 2, EE, FO, and skin temperature in the region close to BAT depots (Tscv) and in the control region (Tc) were measured at 27 °C and after 90 min cold exposure at 19 °C in the morning and in the evening. In STUDY 1, DIT and FO after breakfast was higher in the High-BAT group than in the Low-BAT group (P < 0.05), whereas those after dinner were comparable in the two groups. FO in the High-BAT group was higher after breakfast than after dinner (P < 0.01). In STUDY 2, cold-induced increases in EE (CIT), FO, and Tscv relative to Tc in the morning were higher in the High-BAT group than in the Low-BAT group (P < 0.05), whereas those after dinner were comparable in the two groups. CIT in the High-BAT group tended to be higher in the morning than in the evening (P = 0.056). BAT-associated NST and FO were evident in the morning, but not in the evening, suggesting that the activity of human BAT is higher in the morning than in the evening, and thus may be involved in the association of an eating habit of breakfast skipping with obesity and related metabolic disorders.
• Is the use of high correlated color temperature light at night related to delay of sleep timing in university students? A cross-country study in Japan and China

  Shigekazu Higuchi, Yandan Lin, Jingjing Qiu, Yichi Zhang, Michihiro Ohashi, Sang-il Lee, Shingo Kitamura, Akira Yasukouchi

  Journal of Physiological Anthropology 40 (1) 7 - 7 2021/06 

  Blue-enriched white light at night has the potential to delay the circadian rhythm in daily life. This study was conducted to determine whether the use of high correlated color temperature (CCT) light at home at night is associated with delay of sleep timing in university students. The survey was conducted in 2014–2015 in 447 university students in Japan and 327 students in China. Habitual sleep timing and type of CCT light at home were investigated by using a self-administered questionnaire. The Japanese students were significantly later than the Chinese students in bedtime, wake time, and midpoint of sleep. They were asked whether the lighting in the room where they spend most of their time at night was closer to warm color (low CCT) or daylight color (high CCT). The amount of light exposure level during daily life was measured for at least 1 week by the use of a light sensor in 60 students in each country. The percentages of participants who used high CCT lighting at night were 61.6% for Japanese students and 80.8% for Chinese students. Bedtime and sleep onset time on school days and free days were significantly later in the high CCT group than in the low CCT group in Japan. The midpoint of sleep in the high CCT group was significantly later than that in the low CCT group on free days but not on school days. On the other hand, none of the sleep measurements on school days and free days were significantly different between the high CCT and low CCT groups in China. Illuminance level of light exposure during the night was significantly higher in Japanese than in Chinese, but that in the morning was significantly higher in China than in Japan. The use of high CCT light at night is associated with delay of sleep timing in Japanese university students but not in Chinese university students. The effects of light at night on sleep timing and circadian rhythm may be complicated by other lifestyle factors depending on the country.

  Abstract Background Blue-enriched white light at night has the potential to delay the circadian rh......See More

  × Blue-enriched white light at night has the potential to delay the circadian rhythm in daily life. This study was conducted to determine whether the use of high correlated color temperature (CCT) light at home at night is associated with delay of sleep timing in university students. The survey was conducted in 2014–2015 in 447 university students in Japan and 327 students in China. Habitual sleep timing and type of CCT light at home were investigated by using a self-administered questionnaire. The Japanese students were significantly later than the Chinese students in bedtime, wake time, and midpoint of sleep. They were asked whether the lighting in the room where they spend most of their time at night was closer to warm color (low CCT) or daylight color (high CCT). The amount of light exposure level during daily life was measured for at least 1 week by the use of a light sensor in 60 students in each country. The percentages of participants who used high CCT lighting at night were 61.6% for Japanese students and 80.8% for Chinese students. Bedtime and sleep onset time on school days and free days were significantly later in the high CCT group than in the low CCT group in Japan. The midpoint of sleep in the high CCT group was significantly later than that in the low CCT group on free days but not on school days. On the other hand, none of the sleep measurements on school days and free days were significantly different between the high CCT and low CCT groups in China. Illuminance level of light exposure during the night was significantly higher in Japanese than in Chinese, but that in the morning was significantly higher in China than in Japan. The use of high CCT light at night is associated with delay of sleep timing in Japanese university students but not in Chinese university students. The effects of light at night on sleep timing and circadian rhythm may be complicated by other lifestyle factors depending on the country.
• Melatonin suppression during a simulated night shift in medium intensity light is increased by 10-minute breaks in dim light and decreased by 10-minute breaks in bright light

  Sang-il Lee, Saki Kinoshita, Anna Noguchi, Taisuke Eto, Michihiro Ohashi, Yuki Nishimura, Kaho Maeda, Yuki Motomura, Yasuhiro Awata, Shigekazu Higuchi

  Chronobiology International 37 (6) 897 - 909 0742-0528 2020/04 [Refereed][Not invited]
  
• Melatonin suppression and sleepiness in children exposed to blue-enriched white LED lighting at night

  Sang-il Lee, Kouhei Matsumori, Kana Nishimura, Yuki Nishimura, Yuki Ikeda, Taisuke Eto, Shigekazu Higuchi

  Physiological Reports 6 (24) e13942  2018/12 [Refereed][Not invited]
   

  © 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society. Light-induced melatonin suppression in children is reported to be more sensitive to white light at night than that in adults; however, it is unclear whether it depends on spectral distribution of lighting. In this study, we investigated the effects of different color temperatures of LED lighting on children's melatonin secretion during the night. Twenty-two healthy children (8.9 ± 2.2 years old) and 20 adults (41.7 ± 4.4 years old) participated in this study. A between-subjects design with four combinations, including two age groups (adults and children) and the two color temperature conditions (3000 K and 6200 K), was used. The experiment was conducted for two consecutive nights. On the first night, saliva samples were collected every hour under a dim light condition (<30 lx). On the second night, the participants were exposed to either color temperature condition. Melatonin suppression in children was greater than that in adults at both 3000 K and 6200 K condition. The 6200 K condition resulted in greater melatonin suppression than did the 3000 K condition in children (P < 0.05) but not in adults. Subjective sleepiness in children exposed to 6200 K light was significantly lower than that in children exposed to 3000 K light. In children, blue-enriched LED lighting has a greater impact on melatonin suppression and it inhibits the increase in sleepiness during night. Light with a low color temperature is recommended at night, particularly for children's sleep and circadian rhythm.

  © 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Phys......See More

  ש 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society. Light-induced melatonin suppression in children is reported to be more sensitive to white light at night than that in adults; however, it is unclear whether it depends on spectral distribution of lighting. In this study, we investigated the effects of different color temperatures of LED lighting on children's melatonin secretion during the night. Twenty-two healthy children (8.9 ± 2.2 years old) and 20 adults (41.7 ± 4.4 years old) participated in this study. A between-subjects design with four combinations, including two age groups (adults and children) and the two color temperature conditions (3000 K and 6200 K), was used. The experiment was conducted for two consecutive nights. On the first night, saliva samples were collected every hour under a dim light condition (<30 lx). On the second night, the participants were exposed to either color temperature condition. Melatonin suppression in children was greater than that in adults at both 3000 K and 6200 K condition. The 6200 K condition resulted in greater melatonin suppression than did the 3000 K condition in children (P < 0.05) but not in adults. Subjective sleepiness in children exposed to 6200 K light was significantly lower than that in children exposed to 3000 K light. In children, blue-enriched LED lighting has a greater impact on melatonin suppression and it inhibits the increase in sleepiness during night. Light with a low color temperature is recommended at night, particularly for children's sleep and circadian rhythm.
• Study on spectral sensitivity of pupillary light reflex: comparison of children and young adults

  Taisuke Eto, Kouhei Matsumori, Sang-il Lee, Shigekazu Higuchi

  Japanese Journal of Physiological Anthropology 日本生理人類学会 23 (2) 63 - 67 1342-3215 2018/03 [Refereed][Not invited]
   

  Age-related decrease of crystalline lens transmittance is thought to be a factor affecting non-image forming (NIF)responses such as melatonin suppression and pupillary light reflex (PLR). In this study, we estimated pupillary spectralsensitivities of children and young adults and we compared them. Fourteen healthy primary school children andthirty healthy university students participated in the present study. The estimated spectral response curves tendedto differ between the child group and the adult group (F-test, p ＆lt; 0.1), and their peak sensitivities were 474.2 nm and479.7 nm, respectively. Our findings indicate that spectral sensitivity of PLR to light depends on age, supporting thepossibility that age-related change in lens transmittance is associated with NIF responses.

  Age-related decrease of crystalline lens transmittance is thought to be a factor affecting non-image......See More

  ×Age-related decrease of crystalline lens transmittance is thought to be a factor affecting non-image forming (NIF)responses such as melatonin suppression and pupillary light reflex (PLR). In this study, we estimated pupillary spectralsensitivities of children and young adults and we compared them. Fourteen healthy primary school children andthirty healthy university students participated in the present study. The estimated spectral response curves tendedto differ between the child group and the adult group (F-test, p ＆lt; 0.1), and their peak sensitivities were 474.2 nm and479.7 nm, respectively. Our findings indicate that spectral sensitivity of PLR to light depends on age, supporting thepossibility that age-related change in lens transmittance is associated with NIF responses.
• L-Serine Enhances Light-Induced Circadian Phase Resetting in Mice and Humans

  Shinobu Yasuo, Ayaka Iwamoto, Sang-il Lee, Shotaro Ochiai, Rina Hitachi, Satomi Shibata, Nobuo Uotsu, Chie Tarumizu, Sayuri Matsuoka, Mitsuhiro Furuse, Shigekazu Higuchi

  The Journal of Nutrition 147 (12) 2347 - 2355 2017/10 [Refereed][Not invited]
  
• An ancestral haplotype of the human PERIOD2 gene associates with reduced sensitivity to light-induced melatonin suppression

  Tokiho Akiyama, Takafumi Katsumura, Shigeki Nakagome, Sang-il Lee, Keiichiro Joh, Hidenobu Soejima, Kazuma Fujimoto, Ryosuke Kimura, Hajime Ishida, Tsunehiko Hanihara, Akira Yasukouchi, Yoko Satta, Shigekazu Higuchi, Hiroki Oota

  PLOS ONE 12 (6) (e0178373)  1932-6203 2017/06 [Refereed][Not invited]
   

  Humans show various responses to the environmental stimulus in individual levels as "physiological variations." However, it has been unclear if these are caused by genetic variations. In this study, we examined the association between the physiological variation of response to light-stimulus and genetic polymorphisms. We collected physiological data from 43 subjects, including light-induced melatonin suppression, and performed haplotype analyses on the clock genes, PER2 and PER3, exhibiting geographical differentiation of allele frequencies. Among the haplotypes of PER3, no significant difference in light sensitivity was found. However, three common haplotypes of PER2 accounted for more than 96% of the chromosomes in subjects, and 1 of those 3 had a significantly low-sensitive response to light-stimulus (P < 0.05). The homozygote of the low-sensitive PER2 haplotype showed significantly lower percentages of melatonin suppression (P 0.05), and the heterozygotes of the haplotypes varied their ratios, indicating that the physiological variation for light-sensitivity is evidently related to the PER2 polymorphism. Compared with global haplotype frequencies, the haplotype with a low-sensitive response was more frequent in Africans than in non-Africans, and came to the root in the phylogenetic tree, suggesting that the low light-sensitive haplotype is the ancestral type, whereas the other haplotypes with high sensitivity to light are the derived types. Hence, we speculate that the high light-sensitive haplotypes have spread throughout the world after the Out-of-Africa migration of modern humans.

  Humans show various responses to the environmental stimulus in individual levels as "physiological v......See More

  ×Humans show various responses to the environmental stimulus in individual levels as "physiological variations." However, it has been unclear if these are caused by genetic variations. In this study, we examined the association between the physiological variation of response to light-stimulus and genetic polymorphisms. We collected physiological data from 43 subjects, including light-induced melatonin suppression, and performed haplotype analyses on the clock genes, PER2 and PER3, exhibiting geographical differentiation of allele frequencies. Among the haplotypes of PER3, no significant difference in light sensitivity was found. However, three common haplotypes of PER2 accounted for more than 96% of the chromosomes in subjects, and 1 of those 3 had a significantly low-sensitive response to light-stimulus (P < 0.05). The homozygote of the low-sensitive PER2 haplotype showed significantly lower percentages of melatonin suppression (P 0.05), and the heterozygotes of the haplotypes varied their ratios, indicating that the physiological variation for light-sensitivity is evidently related to the PER2 polymorphism. Compared with global haplotype frequencies, the haplotype with a low-sensitive response was more frequent in Africans than in non-Africans, and came to the root in the phylogenetic tree, suggesting that the low light-sensitive haplotype is the ancestral type, whereas the other haplotypes with high sensitivity to light are the derived types. Hence, we speculate that the high light-sensitive haplotypes have spread throughout the world after the Out-of-Africa migration of modern humans.
• PHYSIOLOGICAL EFFECTS OF BLUE LIGHT AND RED LIGHT AT NIGHT: MEASUREMENT DEPENDENCE AND CORRELATION OF SUBJECTIVE IMPRESSION

  Shotaro OCHIAI, Kazuki HARADA, Sang-il LEE, Shigekazu HIGUCHI

  Japanese Journal of Physiological Anthropology 日本生理人類学会 22 (2) 69 - 76 2017/05 [Refereed][Not invited]
   

  The aim of the present study was to determine the measurement dependence of the effects of color light andto clarify the correlation between physiological responses and subjective impression. Seventeen male universitystudents without color vision deficiency were exposed to blue light and red light (200 lx at eye level) at night forthree hours. The effects of blue light on pupil constriction and melatonin suppression were significantly greater thanthe effects of red light. On the other hand, heart rate tended to be higher under the red light condition. There wasno significant difference between the effects of blue light and red light on rectal temperature or alertness. Individualvariations in the subjective impression of light were correlated with heart rate and rectal temperature but not withmelatonin concentration or pupil constriction. The results suggest that the physiological effects of light depend onmeasurements and that these variations may be influenced by subjective impression.

  The aim of the present study was to determine the measurement dependence of the effects of color lig......See More

  ×The aim of the present study was to determine the measurement dependence of the effects of color light andto clarify the correlation between physiological responses and subjective impression. Seventeen male universitystudents without color vision deficiency were exposed to blue light and red light (200 lx at eye level) at night forthree hours. The effects of blue light on pupil constriction and melatonin suppression were significantly greater thanthe effects of red light. On the other hand, heart rate tended to be higher under the red light condition. There wasno significant difference between the effects of blue light and red light on rectal temperature or alertness. Individualvariations in the subjective impression of light were correlated with heart rate and rectal temperature but not withmelatonin concentration or pupil constriction. The results suggest that the physiological effects of light depend onmeasurements and that these variations may be influenced by subjective impression.
• Late circadian phase in adults and children is correlated with use of high color temperature light at home at night

  Shigekazu Higuchi, Sang-il Lee, Tomoaki Kozaki, Tetsuo Harada, Ikuo Tanaka

  CHRONOBIOLOGY INTERNATIONAL 33 (4) 448 - 452 0742-0528 2016 [Refereed][Not invited]
   

  Light is the strongest synchronizer of human circadian rhythms, and exposure to residential light at night reportedly causes a delay of circadian rhythms. The present study was conducted to investigate the association between color temperature of light at home and circadian phase of salivary melatonin in adults and children. Twenty healthy children ( mean age: 9.7 year) and 17 of their parents ( mean age: 41.9 years) participated in the experiment. Circadian phase assessments were made with dim light melatonin onset ( DLMO). There were large individual variations in DLMO both in adults and children. The average DLMO in adults and in children were 21: 50 +/- 1: 12 and 20: 55 +/- 0: 44, respectively. The average illuminance and color temperature of light at eye level were 139.6 +/- 82.7 lx and 3862.0 +/- 965.6 K, respectively. There were significant correlations between color temperature of light and DLMO in adults ( r = 0.735, p < 0.01) and children ( r = 0.479, p < 0.05), although no significant correlations were found between illuminance level and DLMO. The results suggest that high color temperature light at home might be a cause of the delay of circadian phase in adults and children.

  Light is the strongest synchronizer of human circadian rhythms, and exposure to residential light at......See More

  ×Light is the strongest synchronizer of human circadian rhythms, and exposure to residential light at night reportedly causes a delay of circadian rhythms. The present study was conducted to investigate the association between color temperature of light at home and circadian phase of salivary melatonin in adults and children. Twenty healthy children ( mean age: 9.7 year) and 17 of their parents ( mean age: 41.9 years) participated in the experiment. Circadian phase assessments were made with dim light melatonin onset ( DLMO). There were large individual variations in DLMO both in adults and children. The average DLMO in adults and in children were 21: 50 +/- 1: 12 and 20: 55 +/- 0: 44, respectively. The average illuminance and color temperature of light at eye level were 139.6 +/- 82.7 lx and 3862.0 +/- 965.6 K, respectively. There were significant correlations between color temperature of light and DLMO in adults ( r = 0.735, p < 0.01) and children ( r = 0.479, p < 0.05), although no significant correlations were found between illuminance level and DLMO. The results suggest that high color temperature light at home might be a cause of the delay of circadian phase in adults and children.
• Individual Differences in Effects of Light on Circadian Rhythm and Melatonin Secretion

  Higuchi Shigekazu, Lee Sang-il

  Journal of the Illuminating Engineering Institute of Japan 一般社団法人照明学会 99 (1) 20 - 24 0019-2341 2015/01 [Refereed][Invited]
   

  Light exposure at night affects the human circadian system and is a possible cause of delayed sleep timing and circadian rhythm. It has been found that blue light has more impact on circadian rhythm and that even ordinary room light can suppress melatonin secretion at night. On the other hand, there is a large individual difference in light responsiveness. In order to recommend countermeasures and guidelines for light at night, it might be important to consider individual differences and the factors involved. In this paper, examples of inter- and intra-individual differences in the effects of light on circadian rhythm and melatonin secretion are introduced, and factors involved, including age, ethnicity, gene polymorphism and life style, are discussed.

  Light exposure at night affects the human circadian system and is a possible cause of delayed sleep ......See More

  ×Light exposure at night affects the human circadian system and is a possible cause of delayed sleep timing and circadian rhythm. It has been found that blue light has more impact on circadian rhythm and that even ordinary room light can suppress melatonin secretion at night. On the other hand, there is a large individual difference in light responsiveness. In order to recommend countermeasures and guidelines for light at night, it might be important to consider individual differences and the factors involved. In this paper, examples of inter- and intra-individual differences in the effects of light on circadian rhythm and melatonin secretion are introduced, and factors involved, including age, ethnicity, gene polymorphism and life style, are discussed.
• Influence of Light at Night on Melatonin Suppression in Children

  Shigekazu Higuchi, Yuki Nagafuchi, Sang-il Lee, Tetsuo Harada

  JOURNAL OF CLINICAL ENDOCRINOLOGY & METABOLISM 99 (9) 3298 - 3303 0021-972X 2014/09 [Refereed][Not invited]
   

  Context: The sensitivity of melatonin to light suppression is expected to be higher in children because children have large pupils and pure crystal lenses. However, melatonin suppression by light in children remains unclear. Objective: We investigated whether light-induced melatonin suppression in children is larger than that in adults. Methods: Thirty-three healthy primary school children (meanage, 9.2 +/- 1.5 y) and 29 healthy adults (meanage, 41.6 +/- 4.7 y) participated in two experiments. In the first experiment, salivary melatonin concentrations in 13 children and 13 adults were measured at night under a dim light (<30 lux) and a moderately bright light (580 lux) in an experimental facility. Pupil diameters were also measured under dim light and bright light. In the second experiment, melatonin concentrations in 20 children and 16 adults were measured under dim light in the experimental facility and under room light at home (illuminance, 140.0 +/- 82.7 lux). Results: In experiment 1, the melatonin concentration was significantly decreased by exposure to moderately bright light in both adults and children. Melatonin suppression was significantly larger in children (88.2%; n = 5) than in adults (46.3%; n = 6; P < .01), although the data for some participants were excluded because melatonin concentrations had not yet risen. In experiment 2, melatonin secretion was significantly suppressed by room light at home in children (n = 15; P < .05) but not in adults (n = 11). Conclusion: We found that the percentage of melatonin suppression by light in children was almost twice that in adults, suggesting that melatonin is more sensitive to light in children than in adults at night.

  Context: The sensitivity of melatonin to light suppression is expected to be higher in children beca......See More

  ×Context: The sensitivity of melatonin to light suppression is expected to be higher in children because children have large pupils and pure crystal lenses. However, melatonin suppression by light in children remains unclear. Objective: We investigated whether light-induced melatonin suppression in children is larger than that in adults. Methods: Thirty-three healthy primary school children (meanage, 9.2 +/- 1.5 y) and 29 healthy adults (meanage, 41.6 +/- 4.7 y) participated in two experiments. In the first experiment, salivary melatonin concentrations in 13 children and 13 adults were measured at night under a dim light (<30 lux) and a moderately bright light (580 lux) in an experimental facility. Pupil diameters were also measured under dim light and bright light. In the second experiment, melatonin concentrations in 20 children and 16 adults were measured under dim light in the experimental facility and under room light at home (illuminance, 140.0 +/- 82.7 lux). Results: In experiment 1, the melatonin concentration was significantly decreased by exposure to moderately bright light in both adults and children. Melatonin suppression was significantly larger in children (88.2%; n = 5) than in adults (46.3%; n = 6; P < .01), although the data for some participants were excluded because melatonin concentrations had not yet risen. In experiment 2, melatonin secretion was significantly suppressed by room light at home in children (n = 15; P < .05) but not in adults (n = 11). Conclusion: We found that the percentage of melatonin suppression by light in children was almost twice that in adults, suggesting that melatonin is more sensitive to light in children than in adults at night.
• Nighttime sleep is correlated with effectiveness of inpatient rehabilitation for hemiplegia patients after stroke

  Kenta Hayashida, Shigekazu Higuchi, Jiro Kajiwara, Sang-il Lee, Kenji Kai, Katsuyoshi Setsu, Fumitada Hattori

  SLEEP AND BIOLOGICAL RHYTHMS 12 (3) 220 - 223 1446-9235 2014/07 [Refereed][Not invited]
   

  The purpose of the present study was to clarify the relationship between nighttime sleep and effectiveness of inpatient rehabilitation for stroke patients during convalescence. Fifteen patients participated. Nighttime sleep was measured by actigraph recording. Actual sleep time was significantly correlated with discharge motor Functional Independence Measure (FIM) score and FIM efficiency. Wake after sleep onset (WASO) time was significantly correlated with length of stay. Sleep efficiency was significantly correlated with discharge motor FIM score. Our study showed a relationship between nighttime sleep and effectiveness of inpatient rehabilitation during convalescence after stroke.

  The purpose of the present study was to clarify the relationship between nighttime sleep and effecti......See More

  ×The purpose of the present study was to clarify the relationship between nighttime sleep and effectiveness of inpatient rehabilitation for stroke patients during convalescence. Fifteen patients participated. Nighttime sleep was measured by actigraph recording. Actual sleep time was significantly correlated with discharge motor Functional Independence Measure (FIM) score and FIM efficiency. Wake after sleep onset (WASO) time was significantly correlated with length of stay. Sleep efficiency was significantly correlated with discharge motor FIM score. Our study showed a relationship between nighttime sleep and effectiveness of inpatient rehabilitation during convalescence after stroke.
• Association between the melanopsin gene polymorphism OPN4*Ile394Thr and sleep/wake timing in Japanese university students

  Sang-il Lee, Akiko Hida, Shingo Kitamura, Kazuo Mishima, Shigekazu Higuchi

  JOURNAL OF PHYSIOLOGICAL ANTHROPOLOGY 33 (9) 1880-6791 2014/05 [Refereed][Not invited]
   

  Background: In our previous studies, we found that the Ile394Thr SNP in the melanopsin gene (OPN4) was functionally associated with the pupillary light reflex. This indicates the possibility that OPN4*Ile394Thr is associated with other non-image forming responses. The aim of this study was therefore to determine whether OPN4*Ile394Thr is associated with sleep/wake timing. Methods: A total of 348 healthy Japanese university students participated in this study. Scalp hair was used to genotype the Ile394Thr SNP of OPN4. Sleep habits, including bedtime, wake time and sleep duration, were assessed separately for weekdays and weekends. A total of 328 samples, including 223 samples with TT genotype, 91 with TC genotype and 14 with CC genotype, were used for statistical analysis. No significant difference in age or male/female distribution was found among the three genotype groups. Results: There was no significant difference in circadian preference among the genotype groups. During weekdays, bedtime, wake time and midpoint of sleep for CC subjects were significantly later than those for TT and TC subjects. However, there was no difference between TT and TC subjects in any of their sleep habits. During weekends, bedtime of CC subjects was significantly later than those of TT and TC subjects, and the midpoint of sleep of CC subjects was significantly later than that of TC subjects. Conclusions: Our findings demonstrated that OPN4*Ile394Thr is associated with sleep/wake timing. We also found that the sleep/wake timing of subjects with the CC genotype was later than that of subjects with the TT or TC genotype.

  Background: In our previous studies, we found that the Ile394Thr SNP in the melanopsin gene (OPN4) w......See More

  ×Background: In our previous studies, we found that the Ile394Thr SNP in the melanopsin gene (OPN4) was functionally associated with the pupillary light reflex. This indicates the possibility that OPN4*Ile394Thr is associated with other non-image forming responses. The aim of this study was therefore to determine whether OPN4*Ile394Thr is associated with sleep/wake timing. Methods: A total of 348 healthy Japanese university students participated in this study. Scalp hair was used to genotype the Ile394Thr SNP of OPN4. Sleep habits, including bedtime, wake time and sleep duration, were assessed separately for weekdays and weekends. A total of 328 samples, including 223 samples with TT genotype, 91 with TC genotype and 14 with CC genotype, were used for statistical analysis. No significant difference in age or male/female distribution was found among the three genotype groups. Results: There was no significant difference in circadian preference among the genotype groups. During weekdays, bedtime, wake time and midpoint of sleep for CC subjects were significantly later than those for TT and TC subjects. However, there was no difference between TT and TC subjects in any of their sleep habits. During weekends, bedtime of CC subjects was significantly later than those of TT and TC subjects, and the midpoint of sleep of CC subjects was significantly later than that of TC subjects. Conclusions: Our findings demonstrated that OPN4*Ile394Thr is associated with sleep/wake timing. We also found that the sleep/wake timing of subjects with the CC genotype was later than that of subjects with the TT or TC genotype.
• A missense I394T Variant in Human Melanopsin Gene is Associated with Non-Image Forming Responses、including Pupillary Light Reflex and Sleep/Wake Timing

  Sang-il Lee, Shigekazu Higuchi

  The 1st Asian Conference on Ergonomics and Design (ACED) 2014 [Refereed][Not invited]
  
• Association between melanopsin gene polymorphism (I394T) and pupillary light reflex is dependent on light wavelength

  Sang-il Lee, Akiko Hida, Sei-ichi Tsujimura, Takeshi Morita, Kazuo Mishima, Shigekazu Higuchi

  JOURNAL OF PHYSIOLOGICAL ANTHROPOLOGY 32 (16) 1880-6791 2013/10 [Refereed][Not invited]
   

  Background: Our aim was to determine the association between melanopsin gene polymorphism and pupillary light reflex under diverse photic conditions, including different intensities and wavelengths. Methods: A total of 195 visually corrected subjects volunteered for investigation of the melanopsin gene of single nucleotide polymorphism (SNP) of rs1079610 (I394T). The genotype groups were TT (n = 126), TC (n = 55), and CC (n = 8), and 75 of the subjects, including subjects with TT (n = 34), TC (n = 33), and CC (n = 8) participated in our experiment. Three monochromatic lights with peak wavelengths of 465 nm (blue), 536 nm (green), and 632 nm (red) were prepared, and each light was projected to the subjects with five intensities, 12, 13, 14, 14.5 and 15 log photons/(cm2 s), for one minute. The pupil size of the left eye was measured under each light condition after a 1- minute adaptation. Results: The pupils of the TC + CC genotypes (n = 38) were significantly smaller than those of the TT genotype (n = 31) under a blue (463 nm) light condition with 15 log photons/(cm2 s) (P < 0.05). In contrast, there were no significant differences under green (536 nm) and red (632 nm) light conditions. Conversely, relative pupil constrictions of the TC + CC genotypes were greater than those of the TT genotype under both blue and green conditions with high intensities (14.5 and 15 log photons/(cm2 s)). In contrast, there were no significant differences between genotype groups in pupil size and relative pupilloconstriction under the red light conditions. Conclusions: Our findings suggest that the melanopsin gene polymorphism (I394T) functionally interacts with pupillary light reflex, depending on light intensity and, particularly, wavelength, and that under a light condition fulfilling both high intensity and short wavelength, the pupillary light response of subjects with the C allele (TC + CC) is more sensitive to light than that of subjects with the TT genotype.

  Background: Our aim was to determine the association between melanopsin gene polymorphism and pupill......See More

  ×Background: Our aim was to determine the association between melanopsin gene polymorphism and pupillary light reflex under diverse photic conditions, including different intensities and wavelengths. Methods: A total of 195 visually corrected subjects volunteered for investigation of the melanopsin gene of single nucleotide polymorphism (SNP) of rs1079610 (I394T). The genotype groups were TT (n = 126), TC (n = 55), and CC (n = 8), and 75 of the subjects, including subjects with TT (n = 34), TC (n = 33), and CC (n = 8) participated in our experiment. Three monochromatic lights with peak wavelengths of 465 nm (blue), 536 nm (green), and 632 nm (red) were prepared, and each light was projected to the subjects with five intensities, 12, 13, 14, 14.5 and 15 log photons/(cm2 s), for one minute. The pupil size of the left eye was measured under each light condition after a 1- minute adaptation. Results: The pupils of the TC + CC genotypes (n = 38) were significantly smaller than those of the TT genotype (n = 31) under a blue (463 nm) light condition with 15 log photons/(cm2 s) (P < 0.05). In contrast, there were no significant differences under green (536 nm) and red (632 nm) light conditions. Conversely, relative pupil constrictions of the TC + CC genotypes were greater than those of the TT genotype under both blue and green conditions with high intensities (14.5 and 15 log photons/(cm2 s)). In contrast, there were no significant differences between genotype groups in pupil size and relative pupilloconstriction under the red light conditions. Conclusions: Our findings suggest that the melanopsin gene polymorphism (I394T) functionally interacts with pupillary light reflex, depending on light intensity and, particularly, wavelength, and that under a light condition fulfilling both high intensity and short wavelength, the pupillary light response of subjects with the C allele (TC + CC) is more sensitive to light than that of subjects with the TT genotype.
• Melanopsin gene polymorphism I394T is associated with pupillary light responses in a dose-dependent manner.

  Shigekazu Higuchi, Akiko Hida, Sei-ichi Tsujimura, Kazuo Mishima, Akira Yasukouchi, Sang-il Lee, Youhei Kinjyo, Manabu Miyahira

  PloS one 8 (3) e60310  2013 [Refereed][Not invited]
   

  BACKGROUND: Melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs) play an important role in non-image forming responses to light, such as circadian photoentrainment, light-induced melatonin suppression, and pupillary light response. Although it is known that there are some single nucleotide polymorphisms (SNPs) in the melanopsin (OPN4) gene in humans, the associations of the SNPs with non-image forming responses to light remains unclear. In the present study, we examined the associations of melanopsin gene polymorphisms with pupillary light response. METHODS: Japanese university students (mean age: 21.0 ± 1.7 years) with the genotypes of TT (n = 38), TC (n = 28) and CC (n = 7) at rs1079610 (I394T) located in the coding region participated in the present study. They were matched by age and sex ratio. Dark-adapted pupil size (<1 lx) was first measured. Then steady-state pupil size was measured during exposure to five lighting conditions (10 lx, 100 lx, 1000 lx, 3000 lx, 6000 lx in the vertical direction at eye level). RESULTS: Significant interaction between the genotype of I394T (TT versus TC+CC) and luminance levels was found in pupil size. Under high illuminance levels (1000 lx, 3000 lx and 6000 lx), pupil sizes in subjects with the C allele were significantly smaller than those in subjects with the TT genotype. On the other hand, pupil size in subjects with the C allele under low illuminance (<1 lx) was significantly larger than that in subjects with the TT genotype. Percentages of pupil constriction under high illuminance levels were significantly greater in subjects with the C allele than in subjects with the TT genotype. CONCLUSIONS: Human melanopsin gene polymorphism I394T interacted with irradiance in association with pupil size. This is the first evidence suggesting a functional connection between melanopsin gene polymorphism and pupillary light response as an index of non-image forming response to light.

  BACKGROUND: Melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs) play ......See More

  ×BACKGROUND: Melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs) play an important role in non-image forming responses to light, such as circadian photoentrainment, light-induced melatonin suppression, and pupillary light response. Although it is known that there are some single nucleotide polymorphisms (SNPs) in the melanopsin (OPN4) gene in humans, the associations of the SNPs with non-image forming responses to light remains unclear. In the present study, we examined the associations of melanopsin gene polymorphisms with pupillary light response. METHODS: Japanese university students (mean age: 21.0 ± 1.7 years) with the genotypes of TT (n = 38), TC (n = 28) and CC (n = 7) at rs1079610 (I394T) located in the coding region participated in the present study. They were matched by age and sex ratio. Dark-adapted pupil size (<1 lx) was first measured. Then steady-state pupil size was measured during exposure to five lighting conditions (10 lx, 100 lx, 1000 lx, 3000 lx, 6000 lx in the vertical direction at eye level). RESULTS: Significant interaction between the genotype of I394T (TT versus TC+CC) and luminance levels was found in pupil size. Under high illuminance levels (1000 lx, 3000 lx and 6000 lx), pupil sizes in subjects with the C allele were significantly smaller than those in subjects with the TT genotype. On the other hand, pupil size in subjects with the C allele under low illuminance (<1 lx) was significantly larger than that in subjects with the TT genotype. Percentages of pupil constriction under high illuminance levels were significantly greater in subjects with the C allele than in subjects with the TT genotype. CONCLUSIONS: Human melanopsin gene polymorphism I394T interacted with irradiance in association with pupil size. This is the first evidence suggesting a functional connection between melanopsin gene polymorphism and pupillary light response as an index of non-image forming response to light.
• Event-related potentials reveal subliminal processing of beautiful images

  Sang-il Lee, Satoko Kamiya, Kazuyuki Anekawa, Ryosuke Omura, Takayuki Niahimura, Yeon-kyu Kim, Shigeki Watanuki

  Korean Society for Emotion & Sensibility 163 - 166 2009/05 [Not refereed][Not invited]
  
• Physiological Responses Induced by Pleasant and Unpleasant Film Stimuli

  Yeon-kyu Kim, Yoh Hirata, Yuki Motomura, Ryosuke Omura, Sang-il Lee, Takayuki Nishimura, Shigeki Watanuki

  Korean Society for Emotion & Sensibility 141 - 144 2009 [Not refereed][Not invited]
  
• CHARACTERITICS OF SALIVARY SECRETORY IMMUNOGLOBULIN A(s-IgA) RESPONSES TO PLEASANT AND UNPLEASANT OLFACTORY STIMULI

  Kim YK, Nishimura T, Lee SI, Watanuki S

  Japanese Journal of Physiological Anthropology 日本生理人類学会 14 (2) 67 - 74 1342-3215 2009 [Refereed][Not invited]
   

  In evolutionary perspective, pleasant and unpleasant emotions designed to influence our behavior should be reflected in physiological responses. In this study, pleasant and unpleasant emotional s-IgA responses to olfactory stimuli were investigated. The results revealed that an increase in s-IgA concentration was induced by pleasant olfactory stimuli, while unpleasant olfactory stimuli did not change in s-IgA concentration. These data support the hypothesis that pleasant emotional state may enhance the beneficial effects on immune system. Therefore, s-IgA measurement could offer new insights for the understanding of emotional influence.

  In evolutionary perspective, pleasant and unpleasant emotions designed to influence our behavior sho......See More

  ×In evolutionary perspective, pleasant and unpleasant emotions designed to influence our behavior should be reflected in physiological responses. In this study, pleasant and unpleasant emotional s-IgA responses to olfactory stimuli were investigated. The results revealed that an increase in s-IgA concentration was induced by pleasant olfactory stimuli, while unpleasant olfactory stimuli did not change in s-IgA concentration. These data support the hypothesis that pleasant emotional state may enhance the beneficial effects on immune system. Therefore, s-IgA measurement could offer new insights for the understanding of emotional influence.

• Effects of displaying sunset footage on human time perception

  Yumiko TAN, Jiating LI, Ryusuke SAKAYA, Soomin LEE, Hitoshi WAKABAYASHI, Sang-il LEE

  日本生理人類学会第85回大会  2024/06
• Improving the light environment of private work booths: Evaluation using simulation tools

  Soichiro ABE, Ryusuke SAKAYA, Jiating LI, Yumiko TAN, Hitoshi WAKABAYASHI, Sang-il LEE

  日本生理人類学会第85回大会  2024/06
• Effect of morning light exposure on circadian phase advance: Continuous Light vs. Intermittent Light

  Keiichiro MORITA, Jiating LI, Yumiko TAN, Soomin LEE, Hitoshi WAKABAYASHI, Sang-il LEE

  日本生理人類学会第85回大会  2024/06
• Impact of Brief Dim Light Adaptation during Morning Light Exposure on Circadian Phase Advance

  Sang-il Lee, Shingo Sato, Ryusuke Sakaya, Keiichiro Morita, Yumiko Tan, Jiating Li, Hitoshi Wakabayashi, Soomin Lee

  The 20th International Conference on Environmental Ergonomics  2024/06
• Estimation of Thermal Environment Index Based on Clothing Type Identification Using Image Recognition Technology

  Koichi Ishii, Biplob Biswas Kanti, Yu Watanabe, Ayano Dempoya, Jiating Li, Yumiko Tan, Sang-il Lee, Takuji Iwamura, Shingo Konoshita, Hitoshi Wakabayashi

  The 20th International Conference on Environmental Ergonomics  2024/06
• Enhancing Thermal Sensation Prediction through Infrared Thermography: Integrating Predicted Mean Vote, Clothing Insulation, and Skin Temperature

  Biplob Kanti Biswas, Koichi Ishii, Yu Watanabe, Ayano Dempoya, Jiating Li, Yumiko Tan, Sang-il Lee, Takuji Iwamura, Shingo Konoshita, Hitoshi Wakabayashi

  The 20th International Conference on Environmental Ergonomics  2024/06
• Evaluation of the Effects of Convection and Radiant Cooling System on Thermal Comfort and Physiological Response  [Not invited]

  Masaki Tokiwa, Miki Horihata, Sang-il Lee, Takao Katsura, Hitoshi Wakabayashi

  The 20th International Conference on Environmental Ergonomics  2024/06
• Exploring the Effects of Light on Visual and Non visual Human Responses  [Invited]

  SANG-IL LEE

  Kansei Science and Physiological Anthropology in Japan: Encountering Clothing and Fashion  2023/09
• Evaluating the Effects of Daylight on the Human Circadian System in a Single-Window Room in Sapporo  [Not invited]

  LI Jiating, SAKAYA Ryusuke, TAN Yumiko, WAKABAYASHI Hitoshi, LEE Sangil

  日本睡眠学会第45回定期学術集会・第30回日本時間生物学会学術大会 合同大会  2023/09
• 外界の明暗変化の視覚的情報がヒトの時間認知に与える影響  [Not invited]

  丹由美子, 李佳テイ, 坂彌輔竜, 李スミン, 若林斉, 李相逸

  日本睡眠学会第45回定期学術集会・第30回日本時間生物学会学術大会 合同大会  2023/09
• Effects of the Visual Input of Outdoor Light-Dark Changes on Human Time Perception

  Yumiko Tan, Jiating Li, Ryusuke Sakaya, Hitoshi Wakabayashi, Soomin Lee, Sang-il Lee

  16th International Congress of Physiological Anthropology  2023/09
• 建築設備を活用した電力需給調整に関する研究（その12）曜日・季節に基づく温浴施設と電力需給調整との関係について  [Not invited]

  宮川卓, 赤井 仁志, 若林斉, 李相逸, 天野雄一朗, 藤井 良平

  令和5年度空気調和・衛生工学会大会（福井）  2023/09
• 青色光がワーキングメモリのサブプロセスに与える影響‐脳磁図による検証‐  [Not invited]

  金京室, 大西颯, 李相逸, 横澤宏一

  日本生理人類学会第84回大会  2023/06
• 短波長光のDuty比の違いが眼精疲労と視覚的快適性に与える影響  [Not invited]

  宮崎泰成, 李スミン, 若林斉, 李相逸

  日本生理人類学会第84回大会  2023/06
• Melanopic EDI を用いた室内光環境の推定-照明との位置関係および壁の配色の影響

  坂彌竜輔, 桶谷康祐, 佐藤信吾, 岡田 健, 李相逸

  日本生理人類学会第83回大会  2022/10
• 壁の配色の違いがメラトニン光抑制と覚醒度に及ぼす影響

  岡田 健, 坂彌竜輔, 李佳婷, 宮崎泰成, 丹由美子, 李相逸

  日本生理人類学会第83回大会  2022/10
• 朝の断続的光曝露がヒトの概日リズムの位相と覚醒度に及ぼす影響

  李相逸, 佐藤信吾, 岡田 健, 坂彌竜輔

  日本生理人類学会第83回大会  2022/10
• 光環境の変化が一晩の模擬的夜勤時の概日リズムの位相に及ぼす影響  [Not invited]

  高巣とあ希, 大橋 路弘, 江藤太亮, 境吾見, 李相逸, 元村祐貴, 樋口重和

  日本睡眠学会第47回定期学術集会  2022/06
• 網膜の明暗順応は光の非視覚的作用にどのように働くのか？  [Not invited]

  李相逸

  日本生理人類学会第82回大会（第 2 回日本生理人類学会フロンティアミーティング）  2021/10
• 短波長光の曝露が短期記憶に及ぼす影響  [Not invited]

  岡田健, 金京室, 濱田靖弘, 李相逸

  空気調和衛生工学会北海道支部第55回学術講演会  2021/03
• 照明の色温度、壁の配色、空間的位置関係による屋内光環境の違いがヒトの生理的機能に及ぼす影響－瞳孔の対光反応  [Not invited]

  李相逸, 桶谷康祐, 佐藤信吾, 岡田健, 濱田靖弘

  空気調和衛生工学会北海道支部第55回学術講演会  2021/03
• 体温の日内変動が手部寒冷曝露時の末梢部皮膚温と巧緻性に及ぼす影響  [Not invited]

  鈴木新一, 杉山滉治, 李相逸, 若林斉

  空気調和衛生工学会北海道支部第55回学術講演会  2021/03
• 暑熱環境におけるハッカ精油希釈溶液の塗布が生体応答に及ぼす影響  [Not invited]

  三浦愛子, 江原佑, 松本健太郎, 李相逸, 若林斉, 熊谷千津

  日本生理人類学会第81回大会  2020/10
• 照明の色温度と壁の配色によるメラノピックルクスの違いと簡易的算出方法の提案  [Not invited]

  桶谷康祐, 佐藤信吾, 岡田健, 李相逸, 濱田靖弘

  日本生理人類学会第81回大会  2020/10
• 照明の色温度と壁の配色の組み合わせがヒトの瞳孔の対光反射に与える影響  [Not invited]

  佐藤信吾, 桶谷康祐, 李相逸, 李スミン, 濱田靖弘

  日本生理人類学会第81回大会  2020/10
• 体温の日内変動が手部寒冷曝露に伴う末梢部皮膚温応答におよぼす影響  [Not invited]

  鈴木新一, 杉山滉治, 李相逸, 若林斉

  日本生理人類学会第81回大会  2020/10
• 青色光への曝露下および曝露後の聴覚記憶遂行に与える影響  [Not invited]

  金京室, 李相逸, 岡田健, 横澤宏一

  日本生理人類学会第81回大会  2020/10
• 室内環境とヒトの生理特性に関する研究  [Invited]

  李相逸

  第31回廃棄物資源循環学会研究発表会  2020/09
• 模擬的夜勤時の光曝露による概日リズムの位相後退の個人差  [Not invited]

  眞子杜都, 大橋路弘, 江藤太亮, 西村悠貴, 李相逸, 樋口重和

  日本生理人類学会第80回大会  2019/10
• Effect of L-Serine Intake before Bedtime on Phase of Circadian Rhythm: A Field Study  [Not invited]

  Michihiro Ohashi, Taisuke Eto, Sang-il Lee, Chie Tarumizu, Sayuri Matsuoka, Shinobu Yasuo, Shigekazu Higuchi

  The 14th International Congress of Physiological Anthropology 2019  2019/09
• Effects of Long-term Camping Life without Artificial Night Lighting on Circadian Rhythm in Children  [Not invited]

  Taisuke Eto, Michihiro Ohashi, Yuki Nishimura, Sang-il Lee, Akiko Shikano, Shingo Noi, Shingo Kitamura, Shigekazu Higuchi

  The 14th International Congress of Physiological Anthropology 2019  2019/09
• Controlling Lighting for Night Shift Workers  [Invited]

  Sang-il Lee, Shigekazu Higuchi

  The 14th International Congress of Physiological Anthropology 2019  2019/09
• ヒト褐色脂肪組織活性の日内変動と病態生理学的意義  [Not invited]

  斉藤昌之, 松下真美, 二連木晋輔, 坂根直樹, 李相逸, 若林斉

  第6回時間栄養科学研究会  2019/08
• 就寝前のL-serine摂取が秋冬の実生活における概日リズムに及ぼす影響  [Not invited]

  大橋路弘, 江藤太亮, 李相逸, 垂水千恵, 松岡小百合, 安尾しのぶ, 樋口重和

  日本睡眠学会第44回定期学術集会  2019/06
• Relationships between Melatonin Suppression by Light and Circadian Rhythm in Children  [Not invited]

  Shigekazu HIGUCHI, Kota TAKEOKA, Taisuke ETO, Michihiro OHASHI, Sang-il LEE, Yuki NISHIMURA, Shingo KITAMURA, Akiko SHIKANO, Shingo NOI

  XVI Congress of the European Biological Rhythms Society  2019/06
• 室内における反射光の波長成分の違いがヒトの瞳孔の光反射に及ぼす影響  [Not invited]

  李相逸, 桶谷康祐

  日本生理人類学会第79回大会  2019/06
• 光の非視覚的作用の研究 -世界の動向-  [Not invited]

  李 相逸

  第1回光と生体リズム研究部会  2018/12
• Study on Prior Light History to Light Sensitivity during Night in Children  [Not invited]

  武岡功汰, 江藤太亮, 李相逸, 北村真吾, 樋口重和

  日本生理人類学会第78回大会  2018/10
• 自然の明暗サイクルに従った睡眠/覚醒リズムが子どものメラトニン分泌特性に及ぼす影響

  江藤太亮, 西村佳菜, 武岡功汰, 李相逸, 鹿野晶子, 野井真吾, 北村真吾, 樋口重和

  第25回日本時間生物学会学術大会  2018/10
• Does light with variation in spectrum and intensity during night shift prevent delay of circadian rhythm and sleepiness?  [Not invited]

  Shigekazu Higuchi, Takuya Tsuyama, Anna Noguchi, Sang-il Lee, Kaho Maeda, Yasuhiro Awata

  24th Congress of the European Sleep Research Society  2018/09
• Effects of Short Exposure to Different Light Illuminance in Regular Rest Breaks on Melatonin Suppression and Sleepiness during Simulated Night Work  [Not invited]

  Sang-il Lee, Saki Kinoshita, Anna Noguchi, Taisuke Eto, Kaho Maeda, Yasuhiro Awata, Shigekazu Higuchi

  24th Congress of the European Sleep Research Society  2018/09
• 自然の光環境でのキャンプ生活が子どもの概日リズムに及ぼす影響  [Not invited]

  樋口重和, 西村佳菜, 江藤太亮, 李相逸, 北村真吾, 鹿野晶子, 野井真吾

  日本睡眠学会第43回定期学術集会  2018/07
• 自然環境での光暴露が子どもの瞳孔の対光反射に及ぼす影響  [Not invited]

  江藤太亮, 武岡功汰, 李相逸, 北村真吾, 樋口重和

  日本睡眠学会第43回定期学術集会  2018/07
• 夜勤仮眠中の漸増光照射とメラトニン分泌の関係  [Invited]

  李相逸, 樋口重和

  日本睡眠学会第43回定期学術集会  2018/07
• 実生活におけるL-Serine摂取が概日リズムの光同調に及ぼす影響  [Not invited]

  大橋路弘, 李相逸, 武岡功汰, 江藤太亮, 垂水千恵, 松岡小百合, 安尾しのぶ, 樋口重和

  日本生理人類学会第77回大会  2018/06
• 子どもの概日リズムと自然の明暗サイクルの同調に関する研究  [Not invited]

  西村佳菜, 李相逸, 北村真吾, 樋口重和

  日本生理人類学会第76回大会  2017/11
• 夜勤時の短時間光曝露がメラトニン分泌と眠気に与える影響  [Not invited]

  木之下早紀, 野口杏奈, 李相逸, 阿波田康裕, 樋口重和

  日本生理人類学会第76回大会  2017/11
• Experimental approaches how to prevent light-induced melatonin suppression and circadian rhythm disturbance in shift workers  [Not invited]

  Shigekazu Higuchi, Sang-il Lee

  The 1st International Conference of Occupational Health and Safety  2017/11
• 夜勤中の光によるメラトニン分泌抑制や概日リズムの位相後退をいかに防ぐか  [Invited]

  李相逸, 樋口重和

  第２４回日本時間生物学会学術大会  2017/10
• Entrainment of Circadian Rhythm to Natural Light-Dark Cycle in Children  [Not invited]

  Shigekazu Higuchi, kana Nishimura, Sang-ill Lee, Shingo Kitamura

  2017 SSHB - IAPA Joint Symposium  2017/09
• Promoting effect of L-Serine intake on circadian photoentrainment in humans  [Not invited]

  Sang-il Lee, Kota Takeoka, Chie Tarumizu, Sayuri Matsuoka, Shinobu Yasuo, Shigekazu Higuchi

  2017 SSHB - IAPA Joint Symposium  2017/09
• 低年齢の児童は高年齢の児童と比較して体内時計と睡眠の結びつきが強く就寝時のメディア使用の影響を受けやすい  [Not invited]

  北村真吾, 三島和夫, 樋口重和, 李相逸, 許慧敏

  日本睡眠学会第42回定期学術集会  2017/06
• 瞳孔の対光反射のスペクトル感度に関する研究：大人と子どもの比較  [Not invited]

  江藤太亮, 松森孝平, 李相逸, 樋口重和

  日本生理人類学会第75回大会  2017/06
• Light-induced melatonin suppression in children under exposure to different color temperature of lights at night  [Not invited]

  Sang-il LEE, Kouhei MATSUMORI, Kana NISHIMURA, Humin XU, Takuya TSUYAMA, Shigekazu HIGUCHI

  23rd Congress of the European Sleep Research Society  2016/09
• Delayed circadian phase is associated with late sleep habits in Japanese children  [Not invited]

  Sang-il Lee, Huimin Xu, Kana Nishimura, Takuya Tsuyama, Shigekazu Higuchi

  20th Congress of the European Anthropological Association  2016/08
• Daily light exposure and sleep habits in Japanese and Chinese university students  [Not invited]

  Shigekazu Higuchi, Y Lin, Y Zhang, J Qiu, M Ohashi, Sang-il Lee, Shingo Kitamura, Akira Yasukouchi

  MHAPR symposium-Modernization and Health in the Asia-Pacific Region  2016/08
• LED照明の色温度と年齢の違いが夜間のメラトニン分泌と眠気に及ぼす影響  [Not invited]

  李相逸, 松森孝平, 西村佳菜, 許慧敏, 津山卓也, 樋口重和

  日本睡眠学会第41回定期学術集会  2016/07
• 子どもの睡眠習慣と概日リズム位相の関係  [Not invited]

  許慧敏, 李相逸, 西村佳菜, 北村真吾, 樋口重和

  日本生理人類学会第73回大会  2016/06
• 夜の光環境が大人と子どものメラトニン分泌と眠気に及ぼす影響  [Not invited]

  西村佳菜, 松森孝平, 許慧敏, 李相逸, 樋口重和

  日本生理人類学会第73回大会  2016/06
• 色光に対する非視覚的作用と心理的作用の関係  [Not invited]

  李相逸, 落合将太郎, 樋口重和

  日本視覚学会2016年冬季大会  2016/01
• 子どもを対象とした光の非視覚作用に関する研究  [Not invited]

  松森孝平, 許慧敏, 津山卓也, 西村佳奈, 李相逸, 樋口重和

  日本視覚学会2016年冬季大会  2016/01
• A Proposal to Simplify the Estimation of Characteristic Spectral Responses of Melanopsin to Light Wavelengths  [Not invited]

  Sang-il Lee, Kouhei Matsumori, Shigekazu Higuchi

  The 12th International Congress of Physiological Anthropology  2015/10
• Comparison of Sleep and Chronotypes of Japanese and Chinese University Students  [Not invited]

  Yichi ZHANG, Yandan LIN, Jingjing QIU, Sang-il LEE, Akira YASUKOUCHI, Shigekazu HIGUCHI

  The 12th International Congress of Physiological Anthropology  2015/10
• 夜勤時の光曝露によるメラトニン抑制と概日リズム位相後退の関係：仮眠の有無の影響  [Not invited]

  西剛史, 松森孝平, 李相逸, 小崎智照, 三浦伸彦, 高橋正也, 樋口重和

  第21回日本時間生物学会学術大会  2014/11
• ヒトのメラノプシン遺伝子の一塩基多型I394T と光波長に対する反応特性の関係  [Not invited]

  李相逸, 樋口重和

  第21回日本時間生物学会学術大会  2014/11
• Association between melatonin suppression and circadian phase delay by light exposure during night shift work with and without nap  [Not invited]

  Takeshi Nishi, Kohei Matsumori, Sang-Il Lee, Tomoteru Kozaki, Nobuhiko Miura, Masaya Takahashi, Shigekazu Higuchi

  JSC International Symposium  2014/11
• Association between I394T single nucleotide polymorphism of human melanopsin gene and spectral sensitivity of melanopsin  [Not invited]

  Sang-il Lee, Shigekazu Higuchi

  JSC International Symposium  2014/11
• 家庭で概日リズム位相と夜の照明のメラトニン分泌抑制の評価  [Not invited]

  張亦馳, 西剛史, 落合将太郎, 松森孝平, 李相逸, 小崎智照, 安河内朗, 樋口重和

  第71回日本生理人類学会  2014/11
• Association Between Circadian phase and Light before Bedtime in Japanese Children and their parents  [Not invited]

  Shigekazu Higuchi, Sang-il Lee, Yuki Nagafuchi, Kazuki Harada

  19th Congress of the European Anthropological Association  2014/08
• ヒトのメラノプシン遺伝子多型の一塩基多型と睡眠習慣－就寝時刻と覚醒時刻について  [Not invited]

  李相逸, 樋口重和

  日本睡眠学会第39回定期学術集会  2014/07
• 模擬的夜勤時の仮眠が記憶に及ぼす影響  [Not invited]

  松森孝平, 西剛史, 李相逸, 樋口重和

  日本睡眠学会第39回定期学術集会  2014/07
• Comparison of Light-induced melatonin suppression in children and adults  [Not invited]

  Shigekazu HIGUCHI, Sang-il LEE, Yuki NAGAFUCHI, Tetsuo HARADA

  26th Society for Light Treatment and Biological Rhythms (SLTBR)  2014/06
• The I394T single nucleotide polymorphism of human melanopsin gene is associated with spectral sensitivity of melanopsin  [Not invited]

  Sang-il Lee, Akiko Hida, Shigekazu Higuchi

  26th Society for Light Treatment and Biological Rhythms (SLTBR)  2014/06
• 模擬夜勤時の仮眠とその覚醒前の漸増光照射がメラトニン分泌と睡眠慣性に及ぼす影響  [Not invited]

  西剛史, 李相逸, 松森孝平, 高橋正也, 樋口重和

  第70回日本生理人類学会  2014/06
• A missense I394T Variant in Human Melanopsin Gene is Associated with Non-Image Forming Responses, including Pupillary Light Reflex and Sleep/Wake Timing  [Invited]

  Sang-il Lee, Shigekazu Higuchi

  The 1st Asian Conference on Ergonomics and Design (ACED)  2014/05
• Association between genetic polymorphism of melanopsin photoreceptor and sleep/wake timing  [Invited]

  Sang-il Lee, Shigekazu Higuchi

  The International union of anthropological and ethnological sciences (IUAES)  2014/05
• L-セリン摂取が高照度光曝露によるヒトの概日リズムの位相前進に及ぼす影響  [Not invited]

  落合将太郎, 松森孝平, 李相逸, 垂水千恵, 魚津伸夫, 安尾しのぶ, 樋口重和

  第21回日本時間生物学会学術大会  2014/01
• 模擬的夜勤時の仮眠がメラトニン分泌と概日リズム位相に及ぼす影響  [Not invited]

  西剛史, 松森孝平, 李相逸, 高橋正也, 樋口重和

  日本時間生物学会第20回大会  2013/11
• メラノプシン遺伝子多型I394Tと睡眠習慣の関係  [Not invited]

  李相逸, 肥田昌子, 北村真吾, 稲見香, 三島和夫, 樋口重和

  第69回日本生理人類学会  2013/10
• 異なる色光による生理・心理反応の多様性  [Not invited]

  原田和樹, 落合将太郎, 張亦馳, 李相逸, 樋口重和

  日本生理人類学会第69回大会  2013/10
• Effects of wavelength of light on association between melanopsin gene polymorphism I394T and pupillary light response  [Not invited]

  Sang-il Lee, Shigekazu Higuchi, Akiko Hida, Kazuo Mishima, Sei-ichi Tsujimura, Takeshi Morita

  XIII Congress of the European Biological Rhythms Society  2013/08
• Are phenotypic variations in non-visual effects of light associated with gene polymorphism of melanopsin photoreceptors?  [Not invited]

  Shigekazu Higuchi, Sang-il Lee, Akiko Hida, Sei-ichi Tsujimura, Kazuo Mishima

  11th International Congress of Physiological Anthropology  2013/08
• Non-visual responses to light in children and adults  [Not invited]

  Shigekazu Higuchi, Sang-il Lee, Yuki Nagafuchi, Yandan Lin

  11th International Congress of Physiological Anthropology (ICPA)  2013/08
• メラノプシン遺伝子多型(I394T)と瞳孔の対光反応の関係:光の強度と色光の影響  [Not invited]

  李相逸, 樋口重和, 西剛史, 肥田昌子, 三島和夫, 辻村誠一, 森田健, 稲見香

  第68回日本生理人類学会  2013/06
• 模擬的夜勤時の仮眠がメラトニン分泌に及ぼす影響  [Not invited]

  西剛史, 李相逸, 原田和樹, 永渕祐規, 市川衛, 高橋正也, 樋口重和

  日本生理人類学会第67回大会  2012/11
• メラノプシン遺伝子多型と瞳孔の対光反応の関係  [Not invited]

  李相逸, 福田知美, 原田和樹, 肥田昌子, 三島和夫, 樋口重和

  第19回日本時間生物学会  2012/09
• 夜勤中の仮眠の効果：光によるメラトニン分泌抑制の軽減  [Not invited]

  樋口重和, 西剛史, 李相逸, 原田和樹, 高橋正也

  日本産業衛生学会第86回大会  2012/05
• 生理指標による快・不快情動の推定  [Not invited]

  李相逸, 神谷倫子, 姉川和之, キムヨンキュ, 綿貫茂喜

  日本生理人類学会研究奨励発表会  2010
• 情動誘発時における顔表情と生理反応の特徴に関する研究  [Not invited]

  大村亮介, 姉川和之, 神谷倫子, 李相逸, 西村貴孝, キムヨンキュ, 綿貫茂喜

  日本生理人類学会第60回大会  2009/06
• 日本人における遺伝的多型性と生理心理特性に関する研究  [Not invited]

  西村貴孝, 加藤久美子, 李相逸, 平田陽, キムヨンキュ, 星良和, 近藤隆一郎, 綿貫茂喜

  日本生理人類学会第60回大会  2009/06
• 性格特性と心理特性との関連性  [Not invited]

  加藤久美子, 西村貴孝, 李相逸, キムヨンキュ, 星 良和, 近藤隆一郎, 綿貫茂喜

  日本生理人類学会第60回大会  2009/06
• ストレス作業後の美醜情動誘発画像の呈示が生理反応に与える影響  [Not invited]

  元村祐貴, 大村亮介, 西村貴孝, 李相逸, キムヨンキュ, 綿貫茂喜

  日本生理人類学会第60回大会  2009/06
• 動画による快・不快情動誘発時の顔表情と生理反応の特徴  [Not invited]

  神谷倫子, 姉川和之, 李相逸, 西村貴孝, キムヨンキュ, 綿貫茂喜

  日本生理人類学会第60回大会  2009/06
• Event-related potentials reveal subliminal processing of beautiful images  [Not invited]

  Sang-il Lee, Satoko Kamiya, Kazuyuki Anekawa, Ryosuke Omura, Takayuki Niahimura, Yeon-kyu Kim, Shigeki Watanuki

  Korean Society for Emotion & Sensibility  2009/05
• Physiological Responses Induced by Pleasant and Unpleasant Film Stimuli  [Not invited]

  Yeon-kyu Kim, Yoh Hirata, Yuki Motomura, Ryosuke Omura, Sang-il Lee, Takayuki Nishimura, Shigeki Watanuki

  Korean Society for Emotion & Sensibility  2009/05

• THE SOCIETY OF HEATING, AIR-CONDITIONING AND SANITARY ENGINEERS OF JAPAN   THE JAPANESE SOCIETY OF SLEEP RESEARCH   JAPANESE SOCIETY FOR CHRONOBIOLOGY   JAPAN SOCIETY OF PHYSIOLOGICAL ANTHROPOLOGY   ARCHITECTURAL INSTITUTE OF JAPAN   

• 室内における照明とヒトの位置関係が非視覚的生理反応に与える影響

  日本学術振興会：科学研究費助成事業 基盤研究(C)

  Date (from‐to) : 2023/04 -2026/03 

  Author : 李 相逸
• パルス光を用いた非視覚作用に及ぼす錐体と内因性光感受性網膜神経節細胞の影響の究明

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)

  Date (from‐to) : 2020/04 -2023/03 

  Author : 李 スミン

   

  これまでの科研費による光研究の成果と企業との共同研究の成果を踏まえ、ヒトの非視覚作用に影響する錐体と内因性光感受性網膜神経節細胞（ipRGC）の詳細な働きを究明することを計画した。 波長420 ~ 670 nm の各種単色光を単独に照射、あるいはパルス発光頻度制御により作成した多色光（白色）を照射した時の視覚誘発電位・瞳孔径などの生理反応測定と主観評価を行う。これらによって、非視覚作用に関与する錐体とipRGCの働きを明らかにすると共に、ヒトに優しい人間中心の光環境（Human Centric Lighting）を求めることを目的とした。 しかし、昨年春から始まったコロナの影響で人体を計測する実験は大学のコロナ拡散防止の方針によって規制が多く、被験者を募集するのも難しかった。そこで、予備実験しかできなく、今年から本格的に本実験を行う予定である。以下に予備実験の結果を述べる。 色覚正常な成人７名が６つの予備実験に参加した。この予備実験は本実験の前、被験者に照射する光条件を細かく検討するため行われた。 光条件としては青色（B：ピーク波長470nm）、緑色（G：ピーク波長550nm）、赤色（G：ピーク波長670nm）の各単色光を単独、あるいはパルス発光頻度制御により作成した各多色光（白色）条件を照射した。多色光条件の中ではパルス発光頻度制御よりパルス幅１msのR/G/Bのパルス発光頻度割合を（400ms：300ms：300ms）、（400ms：200ms：400ms）、（400ms：150ms：450ms）にした。その結果、視覚誘発電位と対光瞳孔反応では有意な結果が得られなかった。予備実験の結果を検討し、パルス発光頻度制御のパルスの放射照度、R/G/Bのパルス発光頻度、パルス幅などについて適宜修正する必要があると思われる。

  これまでの科研費による光研究の成果と企業との共同研究の成果を踏まえ、ヒトの非視覚作用に影響する錐体と内因性光感受性網膜神経節細胞（ipRGC）の詳細な働きを究明することを計画した。 波長420 ~ 6......See More

  ×これまでの科研費による光研究の成果と企業との共同研究の成果を踏まえ、ヒトの非視覚作用に影響する錐体と内因性光感受性網膜神経節細胞（ipRGC）の詳細な働きを究明することを計画した。 波長420 ~ 670 nm の各種単色光を単独に照射、あるいはパルス発光頻度制御により作成した多色光（白色）を照射した時の視覚誘発電位・瞳孔径などの生理反応測定と主観評価を行う。これらによって、非視覚作用に関与する錐体とipRGCの働きを明らかにすると共に、ヒトに優しい人間中心の光環境（Human Centric Lighting）を求めることを目的とした。 しかし、昨年春から始まったコロナの影響で人体を計測する実験は大学のコロナ拡散防止の方針によって規制が多く、被験者を募集するのも難しかった。そこで、予備実験しかできなく、今年から本格的に本実験を行う予定である。以下に予備実験の結果を述べる。 色覚正常な成人７名が６つの予備実験に参加した。この予備実験は本実験の前、被験者に照射する光条件を細かく検討するため行われた。 光条件としては青色（B：ピーク波長470nm）、緑色（G：ピーク波長550nm）、赤色（G：ピーク波長670nm）の各単色光を単独、あるいはパルス発光頻度制御により作成した各多色光（白色）条件を照射した。多色光条件の中ではパルス発光頻度制御よりパルス幅１msのR/G/Bのパルス発光頻度割合を（400ms：300ms：300ms）、（400ms：200ms：400ms）、（400ms：150ms：450ms）にした。その結果、視覚誘発電位と対光瞳孔反応では有意な結果が得られなかった。予備実験の結果を検討し、パルス発光頻度制御のパルスの放射照度、R/G/Bのパルス発光頻度、パルス幅などについて適宜修正する必要があると思われる。
• 網膜の光感度の断続的な回復が概日リズムの光同調に及ぼす影響

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)

  Date (from‐to) : 2020/04 -2023/03 

  Author : 李 相逸

   

  生活の夜型化や概日リズムの乱れは、様々な健康問題に関連していると考えられており、その対策が必要である。本研究は、夜型生活や夜間勤務による概日リズムの位相後退を改善することを目標に、朝の光曝露時に網膜の光感受性を高めることが概日リズムの位相前進に及ぼす影響について明らかにすることを目的とした。 今年度（R3）は健康な男子大学生9名を対象に実験室実験を実施した。実験条件は、光感度の「回復あり」と「回復なし」の2条件で、各条件を3泊4日で実施した。1日目は普段の概日リズムの位相を確認（baseline）、2日目は夜更かし（1時～4時に光曝露、500~700 lx）を行い、概日リズムの位相を後退させ、3日目の朝に光曝露を実施し、概日リズムの位相を前進させることにした。3日目の朝の光曝露は8時40分から200分間行った。「回復あり」では「光曝露（1200 lx）30分+Dim（< 5 lx）10分」を5回実施し、「回復なし」では光曝露（1200 lx）を継続した。概日リズムの位相は、Dim環境下でのメラトニンの立ち上がる時刻（DLMO）、または深部体温が最低値を示す時刻とした。その他、主観的眠気（KSS）と客観的眠気（PVT）の経時的変化を測定した。 深部体温の最低値は2日目のデータを基準に「回復あり」条件でわずかな位相前進が見られた半面、「回復なし」ではわずかな位相後退が見られた。しかし、統計的に有意な差は認められなかった。KSSでは、2日目で条件間の差が見られなかったが、3日目で、「回復なし」条件に比べて「回復あり」条件で16時以降の眠気の上昇が早まった。しかし、PVTでは同様な結果が見られなかった。深部体温は睡眠中に測定したため、睡眠のマスキング効果が含まれている。一方で、クロノタイプでグループを分けて分析した結果、夜型傾向の人ほど「回復あり」条件による位相前進効果が表れやすい可能性が確認された。（※メラトニンの分析がまだ終わっていないため、次年度に報告する）

  生活の夜型化や概日リズムの乱れは、様々な健康問題に関連していると考えられており、その対策が必要である。本研究は、夜型生活や夜間勤務による概日リズムの位相後退を改善することを目標に、朝の光曝露時に網膜の......See More

  ×生活の夜型化や概日リズムの乱れは、様々な健康問題に関連していると考えられており、その対策が必要である。本研究は、夜型生活や夜間勤務による概日リズムの位相後退を改善することを目標に、朝の光曝露時に網膜の光感受性を高めることが概日リズムの位相前進に及ぼす影響について明らかにすることを目的とした。 今年度（R3）は健康な男子大学生9名を対象に実験室実験を実施した。実験条件は、光感度の「回復あり」と「回復なし」の2条件で、各条件を3泊4日で実施した。1日目は普段の概日リズムの位相を確認（baseline）、2日目は夜更かし（1時～4時に光曝露、500~700 lx）を行い、概日リズムの位相を後退させ、3日目の朝に光曝露を実施し、概日リズムの位相を前進させることにした。3日目の朝の光曝露は8時40分から200分間行った。「回復あり」では「光曝露（1200 lx）30分+Dim（< 5 lx）10分」を5回実施し、「回復なし」では光曝露（1200 lx）を継続した。概日リズムの位相は、Dim環境下でのメラトニンの立ち上がる時刻（DLMO）、または深部体温が最低値を示す時刻とした。その他、主観的眠気（KSS）と客観的眠気（PVT）の経時的変化を測定した。 深部体温の最低値は2日目のデータを基準に「回復あり」条件でわずかな位相前進が見られた半面、「回復なし」ではわずかな位相後退が見られた。しかし、統計的に有意な差は認められなかった。KSSでは、2日目で条件間の差が見られなかったが、3日目で、「回復なし」条件に比べて「回復あり」条件で16時以降の眠気の上昇が早まった。しかし、PVTでは同様な結果が見られなかった。深部体温は睡眠中に測定したため、睡眠のマスキング効果が含まれている。一方で、クロノタイプでグループを分けて分析した結果、夜型傾向の人ほど「回復あり」条件による位相前進効果が表れやすい可能性が確認された。（※メラトニンの分析がまだ終わっていないため、次年度に報告する）
• Investigation of indoor environment considering human circadian rhythm and arousal level: Relationship between electric lighting and wall color scheme

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Early-Career Scientists

  Date (from‐to) : 2018/04 -2020/03 

  Author : LEE SANG-IL

   

  The aim of this study was to investigate the effect of the difference in indoor light environment due to the combination of lighting color temperature and wall color scheme on non-visual response in humans. We found that the color scheme of the wall is an important factor affecting the indoor light environment (illuminance and irradiance of each light wavelength) regardless of lighting color temperature. We estimated the difference in the non-visual response caused by the direction of the sight and the light exposure position between the lighting and the wall. We also demonstrated the difference in the pupillary light reflex in response to the lighting color temperature, the wall color scheme, and the light exposure position.

  The aim of this study was to investigate the effect of the difference in indoor light environment du......See More

  ×The aim of this study was to investigate the effect of the difference in indoor light environment due to the combination of lighting color temperature and wall color scheme on non-visual response in humans. We found that the color scheme of the wall is an important factor affecting the indoor light environment (illuminance and irradiance of each light wavelength) regardless of lighting color temperature. We estimated the difference in the non-visual response caused by the direction of the sight and the light exposure position between the lighting and the wall. We also demonstrated the difference in the pupillary light reflex in response to the lighting color temperature, the wall color scheme, and the light exposure position.
• Effects of L-serine intake on circadian photoentrainment

  Japan Society for the Promotion of Science：Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)

  Date (from‐to) : 2016/04 -2018/03 

  Author : LEE SANGIL

   

  The aim of this study was to determine whether L-serine intake can promote circadian photoentrainment in real life. Thirty-five healthy university students (18 males and 17 females, 21.5 ± 2.2 yrs) participated in a four-week field study. During the experiment, we did not control participants’ sleep habits and social schedules. The participants were randomly divided into two groups (L-serine and placebo groups, double-blinded). In the L-serine group, a trend of phase advance was found after intake for 10 days, but it was not significantly greater than that of the placebo group. However, the L-serine group showed a relative circadian advance to sleep phase, whereas the placebo groups did not. In the data obtained from winter experiment, we found a greater circadian advance in the L-serine group compared with that in the placebo group.

  The aim of this study was to determine whether L-serine intake can promote circadian photoentrainmen......See More

  ×The aim of this study was to determine whether L-serine intake can promote circadian photoentrainment in real life. Thirty-five healthy university students (18 males and 17 females, 21.5 ± 2.2 yrs) participated in a four-week field study. During the experiment, we did not control participants’ sleep habits and social schedules. The participants were randomly divided into two groups (L-serine and placebo groups, double-blinded). In the L-serine group, a trend of phase advance was found after intake for 10 days, but it was not significantly greater than that of the placebo group. However, the L-serine group showed a relative circadian advance to sleep phase, whereas the placebo groups did not. In the data obtained from winter experiment, we found a greater circadian advance in the L-serine group compared with that in the placebo group.