Figure 4.

Cerebral oxygen delivery (cDO₂, absolute values) of all subjects (n = 9), Mean ±  SD. (a) Normobaric normoxia (NN) and hypobaric hypoxia (HH) conditions at 3,000 m and 5,500 m. (b) NN; normobaric hypoxia (NH); hypobaric hypoxia (HH), and hypobaric normoxia (HN) conditions. Left histograms represent cDO₂ baseline values, middle cDO₂ during hyperventilation, and right cDO₂ at the end of hypercapnia. ^# p < .05 for difference between baseline and hyperventilation values in all conditions; ^★ p < .05 for difference between hyperventilation and hypercapnia values in all conditions; ⁺ p = .014, ⁺ p < .05 for difference with baseline values; and *p = .046 for difference with NN during hypercapnia