| dc.description.abstract | This report is, with emphasis on military operations, a survey of the publicly available literature on the effects on humans of sleep deprivation, starvation, dehydration, fatigue and mental reactions to combat. It was motivated by an interest in improving present war modeling and increasing the awareness of the above mentioned factors in operational analysis, since all these factors are often present and at considerable levels in armed conflicts and in war. It summarizes and discusses the qualitative and quantitative effects of these factors on the physiology, on the cognitive abilities, and on the behavior of humans. The conclusion is that military efficiency will most likely be severely reduced by these factors, already from the first days of maneuver and battle. Furthermore, these factors are linked together and will probably also enhance each other. Innovative and creative thinking are the first qualities that suffer. Then increased slowness and increased error frequency further diminish the military efficiency. The resulting effects may then be: friendly fire incidences, wrong directions of maneuvering, reduced situational awareness, paralysis, unnecessary seeking of cover, absence of fire or inexpedient fire, etc. Besides the reduced military efficiency, the number of casualties caused by mental reactions to combat, often denoted combat stress reactions (CSR) nowadays, increases with increased conflict intensity and may reach considerable levels. Reports from high-intensity warfare in the 20th century show that as many as 50% of the casualties may be caused by CSR. Thus, a rationale for addressing these factors in military regulations and in war modeling exists. | en_GB |