J.ophthalmol.(Ukraine).2016;6:3-5.

https://doi.org/10.31288/oftalmolzh2016635

School-day biorhythms of threshold exposure duration for recognition of test objects in schoolchildren of grades 7 to 11
M.B. Zheliznik, Graduate Student
V.I. Serdiuchenko, Dr Sc (Med)
O.I. Dragomiretska, researcher
Filatov Institute of Eye Diseases and Tissue Therapy, NAMS of Ukraine
Odessa, Ukraine
E-mail: virais@ukr.net
Background: To the best of our knowledge, no study has yet reported on biorhythms of Threshold Exposure Duration for Recognition of Test Objects (TEDRTO).
Purpose: To investigate biorhythms of TEDRTO over a school day in children learning under intensive visual load conditions.
Materials and Methods: Ninety eight ophthalmologically healthy children (aged 13 to 17 years) attending a boarding school with advanced learning of a number of subjects underwent examination. A special electronic apparatus was used to present a test object (a Landolt’s ring having an angular size of 8 minutes of arc) to the child. Binocular TEDRTO measurements were performed at five time points during the day: at 8 o’clock AM, 11 o’clock AM, 2 o’clock PM, 4 o’clock PM, and 8 o’clock PM).
Results: Friedman's non-parametric test demonstrated that TEDRTO values gradually and statistically significantly increased (?? = 52.4; р=0.00000) during a school day. In addition, the number of children with TEDRTO values greater than 1 ms at various times of measurement gradually increased during a school day, and these children usually complained of increased visual fatigue.
Conclusions: There was a statistically significant worsening in TEDRTO values in schoolchildren learning over a day under intensive visual load conditions.
Key words: threshold exposure duration for recognition of test objects, schoolchildren, circadian biorhythms   
References
1.    Aschoff J, editor. Biological Rhythms. New York: Plenum; 1981
Crossref
2.    Kovalenko VV. [Biological rhythms in visual function]. Oftalmol Zh. 1981; 5:297-300 Russian
3.    Moiseeva NI, Sysuev VM. [Time medium and biological rhythms]. Leningrad: Nauka; 1981 Russian
4.    Teterina TP. [Binocular rivalry in diagnosis and treatment of fatigue]. In: [Proceedings of the International Symposium on Ocular Ergonomics Outcomes and Prospects: Moscow, Russia, February 13-15, 1991] Russian
5.    Volkova LP. [Periodicity of visual perception events in a binocular visual act and some aspects of using this phenomenon] [Abstract of Cand Sc (Med) Thesis]. St Petersburg; 1991. 20 p. Russian
6.    Drozdov OG. [Status of ocular convergence and lens accommodation and treatment of its disorders in mildly myopic children]. [Abstract of Cand Sc (Med) Thesis]. Odessa: Filatov Institute of Eye Disease; 1991. 16 p. Russian
7.    Klopots’ka NG. [Efficacy of treatment of various types of amblyopia based on the circadian rhythms of the visual system]. [Abstract of Cand Sc (Med) Thesis]. Odessa: Filatov Institute of Eye Disease; 2003. 19 p. Ukrainian
8.    Pavlichenko NA, Serdiuchenko VI, Danilenko NI. [Biological rhythms in absolute accommodation and visual performance of school children during a school day and school week]. Oftalmol Zh. 1999; 3:174-8 Russian
9.    Klerman EB, Gershengorn HB, Duffy F,  Kronauer, RE. Comparisons of the variability of three markers of the human circadian pacemaker. J Biol Rhythms. 2002 Apr;17(2):181-93
Crossref   Pubmed
10.    Kelly G. Body temperature variability (part 1): a review of the history of body temperature and its variability due to site selection, biological rhythms, fitness, and aging. Altern Med Rev. 2006;11: 278-93
11.    Kr?uchi K, Wirz-Justice A. Circadian rhythm of heat production, heart rate, and skin and core temperature under unmasking conditions in men. Am J Physiol. 1994 Sep;267(3 Pt 2):R819-29
Crossref   Pubmed
12.    Serdiuchenko VI, Zheliznik MB.  [Age-related changes in children’s threshold exposure duration for recognition of test objects]. Oftalmol Zh. 2016; 5:41-3 Ukrainian
Crossref