van den Hout M A, Griez E
J Psychosom Res. 1982;26(2):209-14. doi: 10.1016/0022-3999(82)90038-1.
The effects of CO2 inhalation on subjective state, heart rate and blood pressure were studied in two differently instructed groups, with use of air for placebo. Participants who were told that inhalation would produce a state of pleasant relaxation reported a statistically significant, confirming change when administered CO2, whereas air was found not to alter the subjective state appreciably. Those who had expected unpleasant feelings of tension did show a non-significant change in this respect after CO2 inhalation and no such reaction at all to the placebo. Heart rate and diastolic blood pressure dropped significantly after CO2 intake. Surprisingly, participants were subject to a significant decrease in heart rate upon inhalation of air when relaxation was expected. Finally, a number of theoretical inferences are made and the role of cognitive processes in the clinical use of CO2 therapy is underscored.
在两个接受不同指导的组中，使用空气作为安慰剂，研究了吸入二氧化碳对主观状态、心率和血压的影响。被告知吸入会产生愉悦放松状态的参与者在吸入二氧化碳时报告了具有统计学意义的、得到证实的变化，而发现空气不会明显改变主观状态。那些预期会有不愉快紧张感的人在吸入二氧化碳后在这方面确实有不显著的变化，而对安慰剂则完全没有这种反应。吸入二氧化碳后心率和舒张压显著下降。令人惊讶的是，当预期放松时，参与者在吸入空气时心率会显著下降。最后，得出了一些理论推论，并强调了认知过程在二氧化碳疗法临床应用中的作用。
