Fiziologicheskiĭ zhurnal SSSR imeni I. M. Sechenova
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Fiziol Zh SSSR Im I M Sechenova · Dec 1978
[Nonspecific activation response upon exposure to unanticipated and voluntarily controlled acoustic stimuli].
Normal subjects revealed these components of startle-response to unexpected stimulation followed by no visible wincing: blink reflex, facilitation of spinal motoneurons (augmentation of the H-reflex), the EEG vertex potential, and skin galvanic response. With voluntary, control of the stimulation the components of the response are either absent or less obvious, excepting skin galvanic response. The weakening of the startle-response in this case seems to be associated with the mechanisms of the selective sensory attention and to be determined by cortico-fugal inhibition of reticular interneurons mediating in this response.
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Fiziol Zh SSSR Im I M Sechenova · Jul 1978
[Analysis of the activity of fibers in an entire nerve trunk and a study of impulse frequency in sympathetic preganglionic fibers].
The firing rate in type "B" preganglionic sympathetic fibers during strong pressor reactions varied in different fibers from 0 to 80/sec. With an increase of the pressor reaction, the maximum of the density of frequency distribution shifts from 30--40 to 50--60/sec, previously "silent" fibers becoming involved.
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Fiziol Zh SSSR Im I M Sechenova · May 1978
[Functional state of the vasomotor center in the presence of afferent influences from reflexogenic zones].
Redundant afferentation from reflexogenic zones of the lung and skeletal muscles alters effects of electric stimulation of the midbrain reticular formation and posterior hypothalamic nucleus in the cat due to readjustment of the cortico--subcortical interrelationships and to an increase in the excitability of the brain structures. The data suggest that the functional activity of the vasomotor center depends on the character of afferentation from different reflexogenic zones.