Effects of Hypoxia on Peripheral Visual Response to Dim Stimuli

Kobrick, John L.

doi:10.21236/ada019106

Cited by 2 publications

(2 citation statements)

References 2 publications

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“…Kobrick (1975) reported that hypoxia equivalent to 4,500 and 5,100-m altitudes slowed the response time needed to detect peripheral visual stimuli. Such impaired peripheral vision may also have influenced our results.…”

Section: Discussionmentioning

confidence: 99%

Postural instability at a simulated altitude of 5,000 m before and after an expedition to Mt. Cho-Oyu (8,201 m)

et al. 2010

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To clarify the effects of altitude acclimatization on postural instability at altitudes, six female climbers stood with their eyes open or closed on a force-measuring platform under normoxia (NC) and hypobaric hypoxia, equivalent to a 5,000 m altitude (HC), before and after an expedition to Mt. Cho-Oyu (8,201 m). The expedition extended over 84 days. We recorded sways in the center of foot pressure, electromyograms (EMGs) of lower-leg muscles, blood components and arterial oxygen saturation (SpO(2)). Before the expedition, the maximum amplitude of sway with the eyes open and integrated EMG from the medial gastrocnemius increased for HC. After the expedition, red blood cell (from 423.4 ± 15.4 to 498.0 ± 24.5 × 10(4) μl(-1)), hemoglobin content (from 12.6 ± 0.32 to 14.5 ± 1.00 g/dl) and 2,3-diphosphoglycerate (from 1.93 ± 0.21 to 2.24 ± 0.34 μmol/ml) increased. The SpO(2) under HC increased from 69.2 ± 9.6 to 77.2 ± 10.0%. The maximum amplitude of sway with the eyes open decreased for HC. No difference in the sway path length and integrated EMGs was observed between NC and HC. These results suggest that acclimatization can improve the impaired postural stability on initial arrival at altitudes. However, it is still unclear how long acclimatization period is needed. Further studies are needed to reveal this point.

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Section: Discussionmentioning

confidence: 99%

Postural instability at a simulated altitude of 5,000 m before and after an expedition to Mt. Cho-Oyu (8,201 m)

et al. 2010

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“…In a classical series, McFarland (1937aMcFarland ( , 1937bMcFarland ( , 1938 found significant impairments in arithmetical performance, word recognition, attention level, and short-term memory among high altitude expeditioners at altitudes up to 5400 m. High altitude workers at 4200 m often perceive a poor ability to concentrate (Forster, 1986), and learning complex mental tasks can take longer above 2400 m than at sea level (Denison et al, 1966). Kobrick (1975) found visual alertness to be impaired at 4000 m and higher. It is also interesting that longterm benefits of oxygen therapy on cognitive performance have been seen in the treatment of sea-level patients with hypoxemia caused by chronic obstructive pulmonary disease (Heaton et al, 1983).…”

Section: Neuropsychological Functionmentioning

confidence: 93%

Commuting to High Altitude: Value of Oxygen Enrichment of Room Air

West

2002

High Altitude Medicine & Biology

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Increasingly, lowlanders are commuting to high altitude for commercial, scientific, or defense reasons. Oxygen enrichment of room air at high altitude is a simple but highly effective way of improving sleep quality, mental performance, work efficiency, and general well-being. This review summarizes some of the practical aspects of providing oxygen enrichment including room construction, oxygen concentrators, ventilation levels, costs, use of liquid oxygen, fire hazard, and safe upper limits for oxygen enrichment. The physiological and medical effects of oxygen enrichment are discussed under the headings of sleep, neuropsychological function, and general well-being, productivity, and fatigue. Oxygen enrichment of room air can play a major role in improving living and working conditions for commuters to high altitude.

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Effects of Hypoxia on Peripheral Visual Response to Dim Stimuli

Cited by 2 publications

References 2 publications

Postural instability at a simulated altitude of 5,000 m before and after an expedition to Mt. Cho-Oyu (8,201 m)

Postural instability at a simulated altitude of 5,000 m before and after an expedition to Mt. Cho-Oyu (8,201 m)

Commuting to High Altitude: Value of Oxygen Enrichment of Room Air

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