Assertion: yawning | /r/HasProperty | facilitated
Facets:
value: by comparing the effect on yawning
type: MANNER
Source sentences:
text: Using human college-age subjects, the present study tested the commonly cited but previously untested hypothesis that yawning is facilitated by higher than normal levels of CO 2 or lower than normal levels of O 2 in the blood by comparing the effect on yawning of breathing 100% O 2 and gas mixtures with higher than normal levels of CO 2 (3 or 5%) with compressed air, the control condition.