[The effect of training with computer equipment on the visual analyzer of 1st-grade pupils].

Examination are carried out on 64 school children Ist class from school "104", town of Sofia where computer training on mathematics and mother tongue is introduced in the frames of pedagogic experiment. The studies are performed parallelly at traditional and computer lessons, realized in two variants (with one and two school hours daily). In order to establish the functional status of the visual analyzer during computer training the following methods are used: studying the distance of the nearest point for clear vision (punctum proximum), stability of clear vision, threshold of the electric eye sensitivity, critical frequency of fusing of the light flickerings.

[The effect of instruction with computers on the functional state of first-graders].

A study is carried out on 64 first grade school children for establishing the effect of computer training on the functional status of principally engaged systems with the purpose to determine the optimum duration of work with video terminal during the school day. The examinations are performed before and after computer lessons in mathematics and Bulgarian language in days with one and two lessons, and with the same subjects taught in the traditional way (control group). Traced are the changes in the accommodation, the eye rheobase, critical frequency of fusing the light flickers, resistance, volume and accuracy of the visual perception, static tremor and excretion of sodium and potassium in the saliva.

[Hygienic aspects of youth work brigades].

A comprehensive inquiry study was carried out on living conditions, labour and regime in youth brigades. Furthermore, a complex hygienic-physiological assessment was made of the work of the students gone on agricultural brigades on the base of studies on the changes in the cardiovascular system, energy expenditure, nervous-muscular and thermoregulatory apparatuses, as well as on the functional activity of sympathico-adrenal system. The work, done by the students-members of the brigades, is qualified as moderately heavy, and as heavy only in some labour operations.

[Hygienic and physiological evaluation of the instruction during a 5-day school week].

A longitudinal study of development, reactivity and health state of the students from the initial course, trained during five- and six-day school week was carried out under conditions of full-day organization of the training-educational work. Deviations in the hygienic norms of some moments of daily regime, some results from the dynamics of working capacity and high neurotic morbidity with both forms of organization of trainingeducational work, necessitate essential corrections for its rationalization. Apart from all that, the parallel between the results from the examination of the students, trained during five- and six-day school week in the course of three school years, definitely indicate the following: better working capacity towards the end of school day and week, circulation, realized on a more rational base, better strength indices, lower moment somatic affection and acute morbidity, low number of often-sick-students and more completely healthy students, twice lower neurotic morbidity in favour of the students with a five-day school regime.