Actual and perceived cognitive performance during acute altitude exposure

Abstract

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Hypoxic Hypoxia at Moderate Altitudes: Review of the State of the Science

“…performance parameters. For example, increase in speed of card sorting task completion at 8000 ft (2438 m) ( 50 ); better logical reasoning performance at 8000 ft compared with 5000, 10,000, and 12,000 ft (1524, 3048, and 3658 m) ( 69 ); better cognitive performance and memory scores at 10,000 ft (3048 m) compared to ground and 14,000 ft (4267 m) ( 86 ); and an improved auditory reaction time when HbS o 2 dropped to 90% ( 90 ). Several studies did not fi nd any effects of moderate altitude or equivalent gas mixture on cognitive function at 10,000 ft ( 7 ) They concluded that selected cognitive and affective frontal lobe functions were preserved despite signifi cant HbS o 2 desaturation and a drop in diastolic blood pressure.…”

Air Metabolite Preclusion Reduces Conscious Thought

“…Conscious processes tend to be resource consuming and effortful (Bargh, 1994), and therefore reduced air resource might reduce conscious processes. Increased oxygen intake has been found to benefit (Moss, Scholey, & Wesnes, 1998), and decreased intake to harm (Terry, 2001), conscious processes. Oxygen intake is reduced during sleep, and conscious…”

“…Performance generally was impaired at the lowest oxygen levels. Participants performed more poorly at 10,000 than 14,000 feet on a divided attention task (Terry, 2001). Volunteers exhibited impaired performance on cognitive tasks at simulated higher altitudes (Crowley et al, 1992;Gerard, 2000 (Moss et al, 1998).…”