[Viscously-elastic properties of brain and loss of consciousness by human under acceleration].
The article presents the results of analysis of available empirical data about human tolerance of high g-loads. Consideration is given to the role of cerebral viscous elasticity and brain and skull stem deformations in loss of consciousness due to long-term exposure to +Gz and +Gx loads including g-loads with a high rate of onset. High g-loads and rates of onset can lead to maximum permissible g-dose (delta V)m = g integral(n - 1)dt [M/c] = const invariant with a maximum g-dose or rate of onset. For the head-pelvis and chest-back g-vectors it amounts to (deltaVz)max approximately equal 400 M/c; (nz = 2...15; nz = 2...7,5 g/c) and (deltaVx)max =(10...12)10(3) M/c; (nx = 12..22; nx< or = 0,5g/c), respectively. It is hypothesized that maximum permissible gdose for humans are constants which, probably, characterize buildup of brain damaging() stresses and deformations and ensuing loss of consciousness as a reaction of the brain, stem structures spedfically, to the g-load induced drop of arterial blood and intracranial pressure, and also deterioration of cerebral viscous elasticity (turgor).
Rabinovich
B A
BA
D000054:Acceleration / Q000009:adverse effects*; D001921:Brain / Q000503:physiopathology*; D003071:Cognition / Q000502:physiology*; D004548:Elasticity; D006801:Humans; D008962:Models, Theoretical; D012307:Risk Factors; D014474:Unconsciousness / Q000209:etiology / Q000503:physiopathology*; D014783:Viscosity