{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T04:39:08Z","timestamp":1791952748782,"version":"4.3.4"},"reference-count":118,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,5,17]],"date-time":"2021-05-17T00:00:00Z","timestamp":1621209600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Physiol."],"abstract":"<jats:p>Acute hypobaric hypoxia (HH) is a major physiological threat during high-altitude flight and operations. In military aviation, although hypoxia-related fatalities are rare, incidences are common and are likely underreported. Hypoxia is a reduction in oxygen availability, which can impair brain function and performance of operational and safety-critical tasks. HH occurs at high altitude, due to the reduction in atmospheric oxygen pressure. This physiological state is also partially simulated in normobaric environments for training and research, by reducing the fraction of inspired oxygen to achieve comparable tissue oxygen saturation [normobaric hypoxia (NH)]. Hypoxia can occur in susceptible individuals below 10,000 ft (3,048 m) in unpressurised aircrafts and at higher altitudes in pressurised environments when life support systems malfunction or due to improper equipment use. Between 10,000 ft and 15,000 ft (4,572 m), brain function is mildly impaired and hypoxic symptoms are common, although both are often difficult to accurately quantify, which may partly be due to the effects of hypocapnia. Above 15,000 ft, brain function exponentially deteriorates with increasing altitude until loss of consciousness. The period of effective and safe performance of operational tasks following exposure to hypoxia is termed the time-of-useful-consciousness (TUC). Recovery of brain function following hypoxia may also lag beyond arterial reoxygenation and could be exacerbated by repeated hypoxic exposures or hyperoxic recovery. This review provides an overview of the basic physiology and implications of hypoxia for military aviation and discusses the utility of hypoxia recognition training.<\/jats:p>","DOI":"10.3389\/fphys.2021.665821","type":"journal-article","created":{"date-parts":[[2021,5,17]],"date-time":"2021-05-17T06:20:33Z","timestamp":1621232433000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":111,"title":["Hypoxic Hypoxia and Brain Function in Military Aviation: Basic Physiology and Applied Perspectives"],"prefix":"10.3389","volume":"12","author":[{"given":"David M.","family":"Shaw","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gus","family":"Cabre","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicholas","family":"Gant","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2021,5,17]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"529","DOI":"10.1016\/S0021-9258(18)85018-9","article-title":"The hemoglobin system VI. The oxygen dissociation curve of hemoglobin","volume":"63","author":"Adair","year":"1925","journal-title":"J. Biol. Chem."},{"key":"ref2","doi-asserted-by":"publisher","first-page":"e14372","DOI":"10.14814\/phy2.14372","article-title":"Specific effect of hypobaria on cerebrovascular hypercapnic responses in hypoxia","volume":"8","author":"Aebi","year":"","journal-title":"Phys. Rep."},{"key":"ref3","doi-asserted-by":"publisher","first-page":"845","DOI":"10.3357\/AMHP.5616.2020","article-title":"Cognitive impairment during combined normobaric vs. hypobaric and normoxic vs. hypoxic acute exposure","volume":"91","author":"Aebi","year":"","journal-title":"Aerosp. Med. Hum. Perform."},{"key":"ref4","doi-asserted-by":"publisher","first-page":"R1473","DOI":"10.1152\/ajpregu.91008.2008","article-title":"Integration of cerebrovascular CO2 reactivity and chemoreflex control of breathing: mechanisms of regulation, measurement, and interpretation","volume":"296","author":"Ainslie","year":"2009","journal-title":"Am. J. Phys. Regul. Integr. Comp. Phys."},{"key":"ref5","doi-asserted-by":"publisher","first-page":"1160","DOI":"10.1113\/EP085671","article-title":"Lessons from the laboratory; integrated regulation of cerebral blood flow during hypoxia","volume":"101","author":"Ainslie","year":"2016","journal-title":"Exp. Physiol."},{"key":"ref6","doi-asserted-by":"publisher","first-page":"28","DOI":"10.1016\/j.physbeh.2019.03.022","article-title":"Differential impact of acute hypoxia on event related potentials: impaired task-irrelevant, but preserved task-relevant processing and response inhibition","volume":"206","author":"Altb\u00e4cker","year":"2019","journal-title":"Physiol. Behav."},{"key":"ref7","first-page":"857","article-title":"Mask-on hypoxia training for tactical jet aviators: evaluation of an alternate instructional paradigm","volume":"77","author":"Artino","year":"2006","journal-title":"Aviat. Space Environ. Med."},{"key":"ref8","doi-asserted-by":"publisher","first-page":"547","DOI":"10.3357\/ASEM.2464.2009","article-title":"Normobaric hypoxia training: the effects of breathing-gas flow rate on symptoms","volume":"80","author":"Artino","year":"2009","journal-title":"Aviat. Space Environ. Med."},{"key":"ref9","doi-asserted-by":"publisher","first-page":"1159","DOI":"10.3357\/ASEM.3661.2013","article-title":"Cognition at altitude: impairment in executive and memory processes under hypoxic conditions","volume":"84","author":"Asmaro","year":"2013","journal-title":"Aviat. Space Environ. Med."},{"key":"ref10","doi-asserted-by":"publisher","first-page":"15","DOI":"10.1113\/jp276814","article-title":"Oxygen, evolution and redox signalling in the human brain; quantum in the quotidian","volume":"597","author":"Bailey","year":"2018","journal-title":"J. Physiol. Lond."},{"key":"ref11","doi-asserted-by":"publisher","first-page":"1769","DOI":"10.1113\/EP088005","article-title":"Oxygen and brain death; back from the brink","volume":"104","author":"Bailey","year":"2019","journal-title":"Q. J. Exp. Physiol."},{"key":"ref12","doi-asserted-by":"publisher","first-page":"73","DOI":"10.1089\/ham.2016.0081","article-title":"Surviving without oxygen: how low can the human brain go?","volume":"18","author":"Bailey","year":"2017","journal-title":"High Alt. Med. Biol."},{"key":"ref13","doi-asserted-by":"publisher","first-page":"1967","DOI":"10.1016\/S0140-6736(03)13591-X","article-title":"High-altitude illness","volume":"361","author":"Basnyat","year":"2003","journal-title":"Lancet"},{"key":"ref14","doi-asserted-by":"publisher","first-page":"617","DOI":"10.3357\/AMHP.4709.2017","article-title":"Cognitive deterioration in moderate and severe hypobaric hypoxia conditions","volume":"88","author":"Beer","year":"2017","journal-title":"Aerosp. Med. Hum. Perform."},{"key":"ref15","doi-asserted-by":"publisher","first-page":"146","DOI":"10.1213\/ANE.0000000000001421","article-title":"Effects of acute, profound hypoxia on healthy humans","volume":"124","author":"Bickler","year":"2017","journal-title":"Anesth. Analg."},{"key":"ref16","doi-asserted-by":"publisher","first-page":"813","DOI":"10.1213\/ANE.0b013e318297d763","article-title":"Factors affecting the performance of 5 cerebral oximeters during hypoxia in healthy volunteers","volume":"117","author":"Bickler","year":"2013","journal-title":"Anesth. Analg."},{"key":"ref17","doi-asserted-by":"publisher","first-page":"672","DOI":"10.1097\/PSY.0b013e3181e68e94","article-title":"Feeling lightheaded: the role of cerebral blood flow","volume":"72","author":"Bresseleers","year":"2010","journal-title":"Psychosom. Med."},{"key":"ref18","doi-asserted-by":"publisher","first-page":"212","DOI":"10.1016\/j.resp.2007.04.008","article-title":"Cerebrovascular responses to altitude","volume":"158","author":"Brugniaux","year":"2007","journal-title":"Respir. Physiol. Neurobiol."},{"key":"ref19","first-page":"117","article-title":"Effect of physical activity of airline flight attendants on their time of useful consciousness in a rapid decompression","volume":"47","author":"Busby","year":"1976","journal-title":"Aviat. Space Environ. Med."},{"key":"ref20","first-page":"169","article-title":"In-flight hypoxia incidents in military aircraft: causes and implications for training","volume":"74","author":"Cable","year":"2003","journal-title":"Aviat. Space Environ. Med."},{"key":"ref21","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1016\/j.jns.2011.12.007","article-title":"Post-cardiac arrest brain injury: pathophysiology and treatment","volume":"315","author":"Chalkias","year":"2012","journal-title":"J. Neurol. Sci."},{"key":"ref22","doi-asserted-by":"publisher","first-page":"609","DOI":"10.3357\/ASEM.3273.2012","article-title":"Repeated hypoxic syncope in a helicopter pilot at a simulated altitude of 18,000 feet","volume":"83","author":"Chiang","year":"2012","journal-title":"Aviat. Space Environ. Med."},{"key":"ref23","doi-asserted-by":"publisher","first-page":"183","DOI":"10.1152\/jappl.1967.23.2.183","article-title":"Effects of hypoxia and normocarbia on cerebral blood flow and metabolism in conscious man","volume":"23","author":"Cohen","year":"1967","journal-title":"J. Appl. Physiol."},{"key":"ref24","doi-asserted-by":"publisher","first-page":"194","DOI":"10.1183\/20734735.001415","article-title":"Relating oxygen partial pressure, saturation and content: the haemoglobin\u2013oxygen dissociation curve","volume":"11","author":"Collins","year":"2015","journal-title":"Breathe"},{"key":"ref25","doi-asserted-by":"publisher","first-page":"1157","DOI":"10.3357\/ASEM.3145.2011","article-title":"PH2O and simulated hypobaric hypoxia","volume":"82","author":"Conkin","year":"2011","journal-title":"Aviat. Space Environ. Med."},{"key":"ref26","doi-asserted-by":"publisher","first-page":"61","DOI":"10.3357\/AMHP.4421.2016","article-title":"Equivalent air altitude and the alveolar gas equation","volume":"87","author":"Conkin","year":"2016","journal-title":"Aerosp. Med. Hum. Perform."},{"key":"ref27","doi-asserted-by":"publisher","first-page":"975","DOI":"10.3357\/ASEM.2331.2008","article-title":"Critique of the equivalent air altitude model","volume":"79","author":"Conkin","year":"2008","journal-title":"Aviat. Space Environ. Med."},{"key":"ref28","doi-asserted-by":"publisher","first-page":"2","DOI":"10.1186\/s13728-014-0021-6","article-title":"The physiological effects of hypobaric hypoxia versus normobaric hypoxia: a systematic review of crossover trials","volume":"4","author":"Coppel","year":"2015","journal-title":"Extreme Physiol. Med."},{"key":"ref29","doi-asserted-by":"publisher","first-page":"1255","DOI":"10.1152\/japplphysiol.00873.2013","article-title":"Discerning normobaric and hypobaric hypoxia: significance of exposure duration","volume":"116","author":"Debevec","year":"2014","journal-title":"J. Appl. Physiol."},{"key":"ref30","doi-asserted-by":"publisher","first-page":"775","DOI":"10.3357\/ASEM.2941.2011","article-title":"In-flight hypoxia events in tactical jet aviation: characteristics compared to Normobaric training","volume":"82","author":"Deussing","year":"2011","journal-title":"Aviat. Space Environ. Med."},{"key":"ref31","first-page":"666","article-title":"Inspired carbon dioxide during hypoxia: effects on task performance and cerebral oxygen saturation","volume":"78","author":"Dorp","year":"2007","journal-title":"Aviat. Space Environ. Med."},{"key":"ref32","doi-asserted-by":"publisher","first-page":"295","DOI":"10.1002\/ana.25147","article-title":"Terminal spreading depolarization and electrical silence in death of human cerebral cortex","volume":"83","author":"Dreier","year":"2018","journal-title":"Ann. Neurol."},{"key":"ref33","doi-asserted-by":"publisher","first-page":"292","DOI":"10.1113\/jphysiol.1963.sp007257","article-title":"The effect of brief profound hypoxia upon the arterial and venous oxygen tensions in man","volume":"169","author":"Ernsting","year":"1963","journal-title":"J. Physiol."},{"key":"ref34","doi-asserted-by":"publisher","first-page":"S18","DOI":"10.1213\/01.ane.0000285988.35174.d9","article-title":"Dark skin decreases the accuracy of pulse oximeters at low oxygen saturation: The effects of oximeter probe type and gender","volume":"105","author":"Feiner","year":"2007","journal-title":"Anesth. Analg."},{"key":"ref35","first-page":"523","article-title":"Depressurization in military aircraft: rates, rapidity, and health effects for 1055 incidents","volume":"76","author":"Files","year":"2005","journal-title":"Aviat. Space Environ. Med."},{"key":"ref36","doi-asserted-by":"publisher","first-page":"61","DOI":"10.1177\/001872088702900106","article-title":"The threshold for hypoxia effects on perceptual-motor performance","volume":"29","author":"Fowler","year":"1987","journal-title":"Hum. Factors"},{"key":"ref37","doi-asserted-by":"publisher","first-page":"1482","DOI":"10.1113\/EP087602","article-title":"Isolating the independent effects of hypoxia and hyperventilation-induced hypocapnia on cerebral haemodynamics and cognitive function","volume":"104","author":"Friend","year":"2019","journal-title":"Q. J. Exp. Physiol."},{"key":"ref38","doi-asserted-by":"publisher","first-page":"1247","DOI":"10.1016\/0002-9343(81)90834-2","article-title":"Brain dysfunction in mild to moderate hypoxia","volume":"70","author":"Gibson","year":"1981","journal-title":"Am. J. Med."},{"key":"ref39","doi-asserted-by":"publisher","first-page":"73","DOI":"10.1080\/21641846.2014.909963","article-title":"Acute and chronic hypoxia: implications for cerebral function and exercise tolerance","volume":"2","author":"Goodall","year":"2014","journal-title":"Fatigue"},{"key":"ref40","author":"Gradwell","year":"2016"},{"key":"ref41","doi-asserted-by":"publisher","first-page":"140","DOI":"10.1056\/NEJMoa0801581","article-title":"Arterial blood gases and oxygen content in climbers on Mount Everest","volume":"360","author":"Grocott","year":"2009","journal-title":"N. Engl. J. Med."},{"key":"ref42","doi-asserted-by":"publisher","first-page":"490","DOI":"10.1152\/jappl.1949.1.7.490","article-title":"Interval of useful consciousness at various altitudes","volume":"1","author":"Hall","year":"1949","journal-title":"J. Appl. Physiol."},{"key":"ref43","doi-asserted-by":"crossref","first-page":"685","DOI":"10.1152\/ajplegacy.1946.145.5.685","article-title":"Blood oxygen saturations and duration of consciousness in anoxia at high altitudes","volume":"145","author":"Hoffman","year":"1946","journal-title":"Am. J. Phys."},{"key":"ref44","doi-asserted-by":"publisher","first-page":"R398","DOI":"10.1152\/ajpregu.00270.2015","article-title":"Hypoxemia, oxygen content, and the regulation of cerebral blood flow","volume":"310","author":"Hoiland","year":"2016","journal-title":"Am. J. Physiol. Regul. Integr. Comp. Physiol."},{"key":"ref45","doi-asserted-by":"publisher","first-page":"968","DOI":"10.3357\/ASEM.3201.2012","article-title":"Altitude decompression sickness incidence among U-2 pilots: 1994-2010","volume":"83","author":"Hundemer","year":"2012","journal-title":"Aviat. Space Environ. Med."},{"key":"ref46","first-page":"1103","article-title":"Determination of the \u201ctime of useful consciousness\u201d (TUC) in repeated exposures to simulated altitude of 25, 000 ft (7620 m)","volume":"59","author":"Izraeli","year":"1988","journal-title":"Aviat. Space Environ. Med."},{"key":"ref47","doi-asserted-by":"publisher","first-page":"64","DOI":"10.3357\/ASEM.2303.2010","article-title":"Severe neurological decompression sickness in a U-2 pilot","volume":"81","author":"Jersey","year":"2010","journal-title":"Aviat. Space Environ. Med."},{"key":"ref48","doi-asserted-by":"publisher","first-page":"962","DOI":"10.3357\/ASEM.3172.2012","article-title":"Hypoxia training: symptom replication in experienced military aircrew","volume":"83","author":"Johnston","year":"2012","journal-title":"Aviat. Space Environ. Med."},{"key":"ref49","doi-asserted-by":"publisher","first-page":"484","DOI":"10.1172\/JCI101995","article-title":"The effects of altered arterial tensions of carbon dioxide and oxygen on cerebral oxygen consumption of normal young men","volume":"27","author":"Kety","year":"1948","journal-title":"J. Clin. Investig."},{"key":"ref50","first-page":"919","article-title":"Pilot cerebral oxygen status during air-to-air combat maneuvering","volume":"73","author":"Kobayashi","year":"2002","journal-title":"Aviat. Space Environ. Med."},{"key":"ref51","doi-asserted-by":"publisher","first-page":"1294","DOI":"10.1038\/jcbfm.2008.15","article-title":"Brief exposure to hyperoxia depletes the glial progenitor pool and impairs functional recovery after hypoxic-ischemic brain injury","volume":"28","author":"Koch","year":"2008","journal-title":"J. Cereb. Blood Flow Metab."},{"key":"ref52","doi-asserted-by":"publisher","first-page":"303","DOI":"10.1016\/0013-4694(88)90002-8","article-title":"Quantitative EEG changes due to hypobaric hypoxia in normal subjects","volume":"69","author":"Kraaier","year":"1988","journal-title":"Electroencephalogr. Clin. Neurophysiol."},{"key":"ref53","doi-asserted-by":"publisher","first-page":"873","DOI":"10.1152\/jappl.1952.4.12.873","article-title":"Relationship of oxygen tension to hemoglobin oxygen saturation in the arterial blood of normal men","volume":"4","author":"Lambertsen","year":"1952","journal-title":"J. Appl. Physiol."},{"key":"ref54","doi-asserted-by":"publisher","first-page":"77","DOI":"10.1016\/s0140-6736(51)91165-8","article-title":"The oxygen paradox. experiments on the effects of oxygen in human anoxia","volume":"1","author":"Latham","year":"1951","journal-title":"Lancet"},{"key":"ref55","doi-asserted-by":"publisher","first-page":"1443","DOI":"10.1113\/EP087967","article-title":"Is alkalosis the dominant factor in hypoxia-induced cognitive dysfunction?","volume":"104","author":"Leacy","year":"2019","journal-title":"Q. J. Exp. Physiol."},{"key":"ref56","doi-asserted-by":"publisher","first-page":"723","DOI":"10.1172\/JCI11003","article-title":"Brain tissue responses to ischemia","volume":"106","author":"Lee","year":"2000","journal-title":"J. Clin. Investig."},{"key":"ref57","doi-asserted-by":"publisher","first-page":"126","DOI":"10.1080\/10508414.2014.892751","article-title":"Effect of mild hypoxia on working memory, complex logical reasoning, and risk judgment","volume":"24","author":"Legg","year":"2014","journal-title":"Int. J. Aviat. Psychol."},{"key":"ref58","doi-asserted-by":"publisher","first-page":"198","DOI":"10.3233\/WOR-2012-0156-198","article-title":"Could mild hypoxia impair pilot decision making in emergencies?","volume":"41","author":"Legg","year":"2012","journal-title":"Work"},{"key":"ref59","doi-asserted-by":"publisher","first-page":"545","DOI":"10.1080\/00140139.2020.1842514","article-title":"Normobaric hypoxia training in military aviation and subsequent hypoxia symptom recognition","volume":"64","author":"Leinonen","year":"2020","journal-title":"Ergonomics"},{"key":"ref60","doi-asserted-by":"publisher","first-page":"231","DOI":"10.1016\/S0034-5687(97)02523-1","article-title":"Ventilation during simulated altitude, normobaric hypoxia and normoxic hypobaria","volume":"107","author":"Loeppky","year":"1997","journal-title":"Respir. Physiol."},{"key":"ref61","doi-asserted-by":"publisher","first-page":"C629","DOI":"10.1152\/ajpcell.00265.2015","article-title":"Oxygen sensing by the carotid body: mechanisms and role in adaptation to hypoxia","volume":"310","author":"L\u00f3pez-Barneo","year":"2016","journal-title":"Am. J. Phys. Cell Phys."},{"key":"ref62","doi-asserted-by":"publisher","first-page":"1007","DOI":"10.1053\/j.jvca.2012.06.010","article-title":"Development and validation of a cerebral oximeter capable of absolute accuracy","volume":"26","author":"MacLeod","year":"2012","journal-title":"J. Cardiothorac. Vasc. Anesth."},{"key":"ref63","doi-asserted-by":"publisher","first-page":"3","DOI":"10.3357\/AMHP.4335.2016","article-title":"Physiological and cognitive effects of acute normobaric hypoxia and modulations from oxygen breathing","volume":"87","author":"Malle","year":"2016","journal-title":"Aerosp. Med. Hum. Perform."},{"key":"ref64","doi-asserted-by":"publisher","first-page":"S10","DOI":"10.1213\/01.ane.0000269522.84942.54","article-title":"The light\u2013tissue interaction of pulse oximetry","volume":"105","author":"Mannheimer","year":"2007","journal-title":"Anesth. Analg."},{"key":"ref65","doi-asserted-by":"publisher","first-page":"3165","DOI":"10.1002\/hbm.24587","article-title":"White matter and hypoxic hypobaria in humans","volume":"40","author":"McGuire","year":"2019","journal-title":"Hum. Brain Mapp."},{"key":"ref66","doi-asserted-by":"publisher","first-page":"719","DOI":"10.1002\/ana.24264","article-title":"White matter hyperintensities and hypobaric exposure","volume":"76","author":"McGuire","year":"2014","journal-title":"Ann. Neurol."},{"key":"ref67","doi-asserted-by":"publisher","first-page":"225","DOI":"10.1016\/j.neubiorev.2017.01.019","article-title":"Effect of acute hypoxia on cognition: a systematic review and meta-regression analysis","volume":"74","author":"McMorris","year":"2017","journal-title":"Neurosci. Biobehav. Rev."},{"key":"ref68","doi-asserted-by":"publisher","first-page":"893","DOI":"10.1113\/jp278673","article-title":"CrossTalk proposal: barometric pressure, independent of PO2, is the forgotten parameter in altitude physiology and mountain medicine","volume":"598","author":"Millet","year":"2021","journal-title":"J. Physiol."},{"key":"ref69","doi-asserted-by":"publisher","first-page":"112","DOI":"10.28920\/dhm49.2.112-118","article-title":"The utility and safety of hypoxia experiences for rebreather divers","volume":"49","author":"Mitchell","year":"2019","journal-title":"Diving Hyperb. Med."},{"key":"ref70","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1017\/S1355617716000965","article-title":"Mechanisms of memory dysfunction during high altitude hypoxia training in military aircrew","volume":"23","author":"Nation","year":"2017","journal-title":"J. Int. Neuropsychol. Soc."},{"key":"ref71","doi-asserted-by":"publisher","first-page":"297","DOI":"10.2147\/PRBM.S51844","article-title":"Cognitive responses to hypobaric hypoxia: implications for aviation training","volume":"7","author":"Neuhaus","year":"2014","journal-title":"Psychol. Res. Behav. Manag."},{"key":"ref72","doi-asserted-by":"publisher","first-page":"231","DOI":"10.2147\/mder.s47319","article-title":"Pulse oximetry: fundamentals and technology update","volume":"7","author":"Nitzan","year":"2014","journal-title":"Med. Dev. Evidence Res."},{"key":"ref73","doi-asserted-by":"publisher","first-page":"847","DOI":"10.1007\/s12576-018-0603-y","article-title":"Hypoxia-induced lowered executive function depends on arterial oxygen desaturation","volume":"68","author":"Ochi","year":"2018","journal-title":"J. Physiol. Sci."},{"key":"ref74","doi-asserted-by":"publisher","first-page":"692","DOI":"10.1113\/expphysiol.2012.068015","article-title":"Effect of acute hypoxia on blood flow in vertebral and internal carotid arteries","volume":"98","author":"Ogoh","year":"2013","journal-title":"Exp. Physiol."},{"key":"ref75","doi-asserted-by":"publisher","first-page":"1443","DOI":"10.1152\/japplphysiol.00169.2017","article-title":"Acute hypoxia in a simulated high-altitude airdrop scenario due to oxygen system failure","volume":"123","author":"Ottestad","year":"2017","journal-title":"J. Appl. Physiol."},{"key":"ref76","doi-asserted-by":"publisher","first-page":"1045","DOI":"10.3357\/AMHP.5173.2018","article-title":"Arterial oxygen saturation, pulse oximetry, and cerebral and tissue oximetry in hypobaric hypoxia","volume":"89","author":"Ottestad","year":"2018","journal-title":"Aerosp. Med. Hum. Perform."},{"key":"ref77","doi-asserted-by":"publisher","first-page":"975","DOI":"10.3357\/ASEM.3315.2012","article-title":"Hypoxic hypoxia at moderate altitudes: review of the state of the science","volume":"83","author":"Petrassi","year":"2012","journal-title":"Aviat. Space Environ. Med."},{"key":"ref78","author":"Phillips","year":"2016"},{"key":"ref79","author":"Phillips","year":"2012"},{"key":"ref80","doi-asserted-by":"publisher","first-page":"357","DOI":"10.3357\/AMHP.3925.2015","article-title":"Cognitive and perceptual deficits of normobaric hypoxia and the time course to performance recovery","volume":"86","author":"Phillips","year":"2015","journal-title":"Aerosp. Med. Hum. Perform."},{"key":"ref81","doi-asserted-by":"publisher","first-page":"1564","DOI":"10.1177\/154193120905302005","article-title":"Moderate intermittent hypoxia: effect on two-choice reaction time followed by a significant delay in recovery","volume":"53","author":"Phillips","year":"2009","journal-title":"Hum. Fact. Ergon. Soc. Ann. Meet. Proc."},{"key":"ref82","doi-asserted-by":"publisher","first-page":"596","DOI":"10.3357\/AMHP.4558.2016","article-title":"Cognition effects of low-grade hypoxia","volume":"87","author":"Pilmanis","year":"2016","journal-title":"Aerosp. Med. Hum. Perform."},{"key":"ref83","doi-asserted-by":"publisher","first-page":"10237","DOI":"10.1073\/pnas.172399499","article-title":"Appraising the brain\u2019s energy budget","volume":"99","author":"Raichle","year":"2002","journal-title":"Proc. Natl. Acad. Sci."},{"key":"ref84","doi-asserted-by":"publisher","first-page":"92","DOI":"10.3357\/AMHP.5228.2019","article-title":"Dry-EEG manifestations of acute and insidious hypoxia during simulated flight","volume":"90","author":"Rice","year":"2019","journal-title":"Aerosp. Med. Hum. Perform."},{"key":"ref85","doi-asserted-by":"publisher","first-page":"677","DOI":"10.3357\/ASEM.3182.2012","article-title":"Differences in cardio-ventilatory responses to hypobaric and normobaric hypoxia: a review","volume":"83","author":"Richard","year":"2012","journal-title":"Aviat. Space Environ. Med."},{"key":"ref86","doi-asserted-by":"publisher","first-page":"22","DOI":"10.1152\/jappl.1966.21.1.22","article-title":"Role of hypocapnia in the circulatory responses to acute hypoxia in man","volume":"21","author":"Richardson","year":"1966","journal-title":"J. Appl. Physiol."},{"key":"ref87","doi-asserted-by":"publisher","first-page":"160","DOI":"10.1080\/13854040590947407","article-title":"Apnea diving: long-term neurocognitive sequelae of repeated hypoxemia","volume":"20","author":"Ridgway","year":"2006","journal-title":"Clin. Neuropsychol."},{"key":"ref88","doi-asserted-by":"publisher","first-page":"1050","DOI":"10.3357\/AMHP.5052.2018","article-title":"Preliminary study of the effects of sequential hypoxic exposures in a simulated flight task","volume":"89","author":"Robinson","year":"2018","journal-title":"Aerosp. Med. Hum. Perform."},{"key":"ref89","first-page":"539","article-title":"The reduced oxygen breath paradigm for hypoxia training: physiological, cognitive, and subjective effects","volume":"72","author":"Sausen","year":"2001","journal-title":"Aviat. Space Environ. Med."},{"key":"ref90","doi-asserted-by":"publisher","first-page":"122","DOI":"10.1007\/s00421-002-0789-8","article-title":"Normo- and hypobaric hypoxia: are there any physiological differences?","volume":"89","author":"Savourey","year":"2003","journal-title":"Eur. J. Appl. Physiol."},{"key":"ref91","doi-asserted-by":"publisher","first-page":"279","DOI":"10.1007\/s10877-012-9348-y","article-title":"Monitoring tissue oxygenation by near infrared spectroscopy (NIRS): background and current applications","volume":"26","author":"Scheeren","year":"2012","journal-title":"J. Clin. Monit. Comput."},{"key":"ref92","doi-asserted-by":"publisher","first-page":"97","DOI":"10.3357\/ASEM.2908.2011","article-title":"Physiological equivalence of normobaric and hypobaric exposures of humans to 25,000 feet (7620 m)","volume":"82","author":"Self","year":"2011","journal-title":"Aviat. Space Environ. Med."},{"key":"ref93","doi-asserted-by":"publisher","first-page":"72","DOI":"10.1007\/BF01617877","article-title":"Errors in 14 pulse oximeters during profound hypoxia","volume":"5","author":"Severinghaus","year":"1989","journal-title":"J. Clin. Monit."},{"key":"ref94","first-page":"1","article-title":"Acute and chronic effects of hypobaric exposure upon the brain,","volume-title":"Undefined.","author":"Sherman","year":"2018"},{"key":"ref95","doi-asserted-by":"publisher","first-page":"168","DOI":"10.1159\/000086206","article-title":"Hyperoxia with 100% oxygen following hypoxia-ischemia increases brain damage in newborn rats","volume":"88","author":"Shimabuku","year":"2005","journal-title":"Neonatology"},{"key":"ref96","doi-asserted-by":"publisher","first-page":"857","DOI":"10.3357\/ASEM.2640.2010","article-title":"Hypoxia awareness training for aircrew: a comparison of two techniques","volume":"81","author":"Singh","year":"2010","journal-title":"Aviat. Space Environ. Med."},{"key":"ref97","first-page":"794","article-title":"Hypoxia symptoms reported during helicopter operations below 10,000 ft: a retrospective survey","volume":"76","author":"Smith","year":"2005","journal-title":"Aviat. Space Environ. Med."},{"key":"ref98","doi-asserted-by":"publisher","first-page":"54","DOI":"10.3357\/ASEM.2013.2008","article-title":"Hypoxia symptoms in military aircrew: long-term recall vs. acute experience in training","volume":"79","author":"Smith","year":"2008","journal-title":"Aviat. Space Environ. Med."},{"key":"ref99","doi-asserted-by":"publisher","first-page":"449","DOI":"10.1007\/s12630-009-9084-z","article-title":"Optimizing preoxygenation in adults","volume":"56","author":"Tanoubi","year":"2009","journal-title":"Can. J. Anesthesia."},{"key":"ref100","doi-asserted-by":"publisher","first-page":"372","DOI":"10.3389\/fphys.2015.00372","article-title":"The impact of different environmental conditions on cognitive function: a focused review","volume":"6","author":"Taylor","year":"2016","journal-title":"Front. Physiol."},{"key":"ref101","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1177\/1179573520988193","article-title":"Hypobaria-induced oxidative stress facilitates homocysteine transsulfuration and promotes glutathione oxidation in rats with mild traumatic brain injury","volume":"13","author":"Tchantchou","year":"2021","journal-title":"J. Cent. Nerv. Sys. Dis."},{"key":"ref102","doi-asserted-by":"publisher","first-page":"654","DOI":"10.3357\/ASEM.2690.2010","article-title":"Hypoxia and flight performance of military instructor pilots in a flight simulator","volume":"81","author":"Temme","year":"2010","journal-title":"Aviat. Space Environ. Med."},{"key":"ref103","year":"2016"},{"key":"ref104","doi-asserted-by":"publisher","first-page":"e0239194","DOI":"10.1371\/journal.pone.0239194","article-title":"Comparison of hypobaric hypoxia symptoms between a recalled exposure and a current exposure","volume":"15","author":"Tu","year":"2020","journal-title":"PLoS One"},{"key":"ref105","doi-asserted-by":"publisher","first-page":"104","DOI":"10.1016\/j.physbeh.2015.02.006","article-title":"Acute hypoxic gas breathing severely impairs cognition and task learning in humans","volume":"142","author":"Turner","year":"2015","journal-title":"Physiol. Behav."},{"key":"ref106","doi-asserted-by":"publisher","first-page":"839","DOI":"10.3357\/AMHP.5665.2020","article-title":"A novel method to measure transient impairments in cognitive function during acute bouts of hypoxia","volume":"91","author":"Uchida","year":"2020","journal-title":"Aerosp. Med. Hum. Perform."},{"key":"ref107","doi-asserted-by":"publisher","first-page":"153","DOI":"10.1016\/S0140-6736(10)61085-9","article-title":"Decompression illness","volume":"377","author":"Vann","year":"2011","journal-title":"Lancet"},{"key":"ref108","doi-asserted-by":"publisher","first-page":"720","DOI":"10.3357\/AMHP.5289.2019","article-title":"Hypoxia hangover and flight performance after normobaric hypoxia exposure in a hawk simulator","volume":"90","author":"Varis","year":"2019","journal-title":"Aerosp. Med. Hum. Perform."},{"key":"ref109","doi-asserted-by":"publisher","first-page":"197","DOI":"10.1007\/s11065-004-8159-4","article-title":"Neuropsychological functioning associated with high-altitude exposure","volume":"14","author":"Viru\u00e9s-Ortega","year":"2004","journal-title":"Neuropsychol. Rev."},{"key":"ref110","doi-asserted-by":"publisher","first-page":"A1","DOI":"10.3357\/ASEM.2576.2011","article-title":"Fifty years of decompression sickness research at brooks AFB, TX: 1960\u20132010","volume":"82","author":"Webb","year":"2011","journal-title":"Aviat. Space Environ. Med."},{"key":"ref111","doi-asserted-by":"publisher","first-page":"33","DOI":"10.1111\/nyas.12719","article-title":"Early history of high-altitude physiology","volume":"1365","author":"West","year":"2016","journal-title":"Ann. N. Y. Acad. Sci."},{"key":"ref112","doi-asserted-by":"publisher","first-page":"1384","DOI":"10.1113\/EP087647","article-title":"Cognitive performance is associated with cerebral oxygenation and peripheral oxygen saturation, but not plasma catecholamines, during graded normobaric hypoxia","volume":"104","author":"Williams","year":"2019","journal-title":"Q. J. Exp. Physiol."},{"key":"ref113","doi-asserted-by":"publisher","first-page":"3261","DOI":"10.1113\/jphysiol.2012.228551","article-title":"Regional brain blood flow in man during acute changes in arterial blood gases","volume":"590","author":"Willie","year":"2012","journal-title":"J. Physiol."},{"key":"ref114","doi-asserted-by":"publisher","first-page":"841","DOI":"10.1113\/jphysiol.2013.268953","article-title":"Integrative regulation of human brain blood flow","volume":"592","author":"Willie","year":"2014","journal-title":"J. Physiol."},{"key":"ref115","doi-asserted-by":"publisher","first-page":"1143","DOI":"10.3357\/ASEM.2987.2011","article-title":"Recollection of hypoxia symptoms Between training events","volume":"82","author":"Woodrow","year":"2011","journal-title":"Aviat. Space Environ. Med."},{"key":"ref116","doi-asserted-by":"publisher","first-page":"141","DOI":"10.1089\/ham.2014.1009","article-title":"Cognitive impairments at high altitudes and adaptation","volume":"15","author":"Yan","year":"2014","journal-title":"High Alt. Med. Biol."},{"key":"ref117","first-page":"72","article-title":"Time of useful consciousness determination in aircrew members with reference to prior altitude chamber experience and age","volume":"71","author":"Yoneda","year":"2000","journal-title":"Aviat. Space Environ. Med."},{"key":"ref118","first-page":"807","article-title":"Comparisons of altitude tolerance and hypoxia symptoms between nonsmokers and habitual smokers","volume":"68","author":"Yoneda","year":"1997","journal-title":"Aviat. Space Environ. 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