Other questions I have on this paper —

- Authors make little acknowledgement of the anticipatory tachycardia seen in HCs. That HC tachycardia could be to the same level as pats. And that some pats had an anticipatory bradycardia.
- No discussion of lack of hyperventilation in the supine anticipatory phase.
- No mention that I could see of the time course of end-tidal CO2 and reduced MCA velocity. Their conjecture is that fear -> hyperventilation -> dec. CO2 -> cerebral vasoconstriction -> inc. cerebral vascular resistance -> dec. cerebral blood flow. If the drop in MCA velocity occurs immediately on standing rather than following the slower onset of respiratory alkalosis - that knocks down their theory.

