This paper deals with the theory of Ivan Petrovich Pavlov(1849-1936), a Russian physiologist, who presented for the first time the systematic theory of the function of the brain that controls the whole behavior of animals, i.e. higher nervous activity through experimental studies. This paper, principally based on Lectures on Conditioned Reflexed(1928), investigates the development of conditioned reflex theory from its beginning by dividing it into three periods. First, during the period from 1898 to 1906, the fundamental concept of conditioned reflex was established and the study of conditioned reflex became an independent discipline. From 1907 to 1916, the second period, Pavlov theorized on higher nervous activity on the basis of extensive data from his laboratory experiments of conditioned reflex. And Pavlov complemented conditioned reflex theory, during the third period from 1916 to 1928, and extended the boundaries of it through applications of conditioned reflex theory to psychopathology and typology. The study contributes to the understanding that conditioned reflex theory was historically developed, and not presented as a complete form from the beginning, and that Pavlov intended to study the higher nervous activity through the method of neurophysiology.
Animal ; English Abstract ; *Higher Nervous Activity ; History of Medicine, 19th Cent. ; History of Medicine, 20th Cent. ; Human ; Neurophysiology/*history ; *Reflex ; Russia

OBJECTIVETo investigate the effect of low intensity and very high frequency (VHF) electromagnetic radiation (170 MHz) on nervous system function and serum enzymes and immune function in human subjects with occupational exposure to VHF.

METHODSTo measure the intensity of VHF and other environmental factors on the spot, to hold the questionnaire about chief complaints, to examine the rheoencephalography and the neurobehavior function, to analyze ALT, AST, ALP and LDH, and IgA, IgM and IgG in experimental group and control group.

RESULTSThe intensity of VHF (direction of antenna: 0 degrees, 10 m and 135 degrees, 20 m) was higher than that of national standard on-the-spot. The incidences of symptoms such as headache, insomnia and amnesia etc. was significantly higher in experimental group (P < 0.01). Rheoencephalography indicated that the raising time of both left [(0.155 3 +/- 0.057 9) s] and right [(0.154 1 +/- 0.059 2) s] in the experimental group after exposure were significantly longer than before exposure [(0.104 4 +/- 0.030 2) s, (0.103 2 +/- 0.030 4) s respectively] or in the control [(0.118 5 +/- 0.056 8) s, (0.117 7 +/- 0.057 5) s respectively, (P < 0.01)]. Neurobehavior function test showed that digital symbol, digital span and pursuit aiming test were decreased after exposure in the experimental group (P < 0.01). Serum enzyme analysis showed that AST, ALP and LDH were significantly increased after exposure in the experimental group (P < 0.01). No marked change was found in IgA level, while the levels of IgM and IgG after exposure in the experimental group especially the latter were significantly increased (P < 0.01).

CONCLUSIONSLow-intensity VHF radiation can decrease the nervous system function in occupationally exposed personnel and induce increase in some kinds of enzymes and immunoglobulins.

Adolescent ; Adult ; Electroencephalography ; radiation effects ; Electromagnetic Fields ; adverse effects ; Higher Nervous Activity ; drug effects ; Humans ; Immunoglobulin G ; blood ; radiation effects ; Immunoglobulin M ; blood ; radiation effects ; Male ; Occupational Exposure ; Radiation Dosage ; Radio Waves ; adverse effects ; T-Lymphocyte Subsets ; immunology ; radiation effects