AER HUNGER

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Our breathing is so regular and automatic that we usually take it for granted. Yet the effects of deprivation are more quickly felt than with any other drive. These effects occur on both a physical and a psychological level, as shown by the fact that when we swallow water while swimming we not only gasp for breath but feel terror-stricken. Moreover, although we have voluntary control over respiration, the physiological need for air is so great that most people cannot ordinarily hold their breath for more than forty seconds. It is possible to increase this interval somewhat by oxygenating the lungs beforehand. A world’s record for staying under water was established by Robert Foster in 1960. After he had hyperventilated with oxygen for thirty minutes, he was able to remain below the surface for thirteen minutes and fifty- two seconds.Our physiological processes are dependent on a continual supply of air, not only to burn the body’s fuel and supply energy, but to flush out carbon dioxide collected in the lungs. When we engage in any strenuous physical activity such as climbing a hill or a long rally in tennis, metabolism may increase sixteen to twenty-four times its normal rate. As a result, we use up our available oxygen supply and our bloodstream does not get a sufficient amount to carry away the waste products that have accumulated during the activity. This creates an “oxygen debt” which we can usually pay back by breathing deeply or by taking a few minutes’ rest. Sighing represents a similar need for air, since respiratory functions areThere are many cases, however, when a shortage of oxygen cannot be so easily repaired. It is a well-known fact that nerve cells in the brain are more sensitive to oxygen lack than in the rest of the body, and complete anoxia (lack of oxygen) need be only brief to cause profound damage. Studies show that people who have been revived after being medically dead for a short period of time often suffer irreparable brain injury. Asphyxia occurring before, during, or just after birth is one of the causes of cerebral palsy, and may produce lifelong mental deficiency. Windle (1958) has demonstrated the effects of anoxia experimentally. He found that oxygen deprivation in adult guinea pigs produced changes in brain structure associated with impaired memory and learning ability, while asphyxia at birth caused changes in the nervous system of monkeys, accompanied by behavior deviations and neurological disorders such as epileptic seizures.The psychological effects of oxygen deprivation have been exhaustively investigated. Miners, balloonists, mountain climbers, and airplane pilots have provided considerable material from their own experiences, and a number of systematic studies have been undertaken in chambers that simulate atmospheric conditions at various altitudes. The reports of pilots flying before the days when oxygen masks and pressurized cabins were in full use are particularly illuminating. They show that when artificial oxygen is not used during a high-altitude climb, the first effect is one of stimulation and wellbeing—but this stage leads imperceptibly to a dulling of sensory, motor, and mental capacities. At sea level, air contains about 21 per cent oxygen. At12,0 feet, where the oxygen content is only two thirds of that amount per cent), there are marked changes in breathing rate. As the ascent continues, breathing becomes more labored and fatigue, drowsiness and headache set in. At an altitude where the oxygen content of the air is only 10 per cent, cyanosis (dusky blue skin, as in a “blue baby”) occurs with a sharp decrease in mental ability. At altitudes above15.0 feet there is increasing impairment of sight (for example, seeing double) followed by impairments in hearing, the sense of pain, time sense, memory, and judgment.The most dangerous aspect of the situation is the fact that the pilot feels that his thinking is clear, his judgment sound, and his sensory abilities in good order (Carlson, 1960). For this reason he may perform irrational acts that endanger himself or others—for instance, one Air Force pilot felt that the horizon was out of place instead of realizing that he was viewing it from an angle; another merely waved at the enemy from an altitude of 19,000 feet; and a third, on a reconnaissance mission during World War I, took eighteen pictures on the same plate. Others were so unaware of their physiological and psychological changes that they continued their upward flight until they lost consciousness at around 25,000 feet. As a result of such experiences, it became common practice for Air Force pilots to hook up their oxygen masks before take-off, since they may not have the judgment or energy to put them on after anoxemia (lack of oxygen in the blood) sets in. Studies of mountaineers who are not acclimated to high altitudes have confirmed these findings and added others. “Mountain sickness” starts as a feeling of exhilaration accompanied by excited talking, quarrelsomeness and generally unreasonable behavior. At around 15.0 feet many climbers feel lightheaded, become hypersensitive to cold, turn blue, and suffer from extreme weakness, nausea, vomiting, and chest ALCOHOLIC ADDICTION 53 discomfort. This may be followed by complete prostration. Emotional reactions that resemble alcoholic intoxication are frequently reported: the individual not only is high, but feels “high.” He has little control over his emotions and may feel euphoric at one moment and depressed or apathetic at another. A study made by McFarland in 1932, in which a man was subjected to simulated altitude conditions, showed that his handwriting gradually deteriorated and became quite illegible at 23,0 feet. He also felt that his feet were a long way off and he could not orient other parts of his body, yet he was well satisfied with his performance and wanted to go much higher. In another study by McFarland (1937), members of an Andean expedition were found to show marked impairment in ability to record words, as well as an increase in faulty associations even after they had been acclimatized. After spending six months in the Andes, ten subjects were found to be incapacitated in practically every type of function. When asked to check a list of possible psychological difficulties, they most often checked “great effort to carry out tasks,” followed in order by “more critical attitudes toward others,” “mental laziness,” “heightened sensory irritability,” “touchiness on various subjects,” “dislike of being told how to do things,” “difficulty in concentrating,” “slowness in reasoning,” “frequently recurring ideas,” and “memory difficulty.” Certain generalizations can be derived from the various studies of oxygen deprivation. First, the critical point appears to be an oxygen concentration equivalent to an altitude of 15,000 feet. Second, both higher and lower mental processes are impaired—the higher probably because of impaired ability to attend, increased distractibility, and sensorimotor incapacity affecting finer coordination. Third, sensory modalities are affected in order, much as in gen eral anesthesia, with vision going before hearing and paralysis occurring in the legs before the arms. Fourth, if the deprivation continues for a long period, as in mines, the effects may be cumulative and lead to permanent memory impairment, mania, and loss of general mental capacity. Fifth, there are large individual differences in reaction to oxygen deprivation. Attempts have also been made to explore the relation between anoxemia and emotional disorder. There is evidence that people who are continually irritable may in some cases be suffering from a chronic oxygen insufficiency that does not allow an adequate interchange between the blood and the tissues. McFarland (1952) found that far more psychoneurotic patients than average individuals collapsed or approached collapse at a simulated altitude of 14,000 feet, indicating that their tolerance for biological stress was much lower than normal. It has also been found that many psychoneurotics show respiratory and water-balance disorders that may be a product of central nervous system disturbances. This suggests that subtle changes in activities like respiration, resulting from inner tension, may cause changes throughout the body. These physical changes may make the individual feel so badly that they affect his emotional well-being, and in this way a vicious cycle of mental illness may be set in motion.Finally, there is some evidence that people who live at higher altitudes tend to be more “temperamental,” more restless and show a greater incidence of neurosis than similar groups living at lower altitudes. These findings are at present only straws in the wind, but they may eventually lead to greater knowledge of the relationship between physical and mental conditions.

Cite this page: N., Sam M.S., "AER HUNGER," in PsychologyDictionary.org, November 28, 2018, https://psychologydictionary.org/aer-hunger/ (accessed December 5, 2021).

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