In certain circumstances, which may include seeing blood or having your eyes examined, your involuntary nervous system behaves as if you were lying down, when actually you are sitting or standing up.
Dalam situasi tertentu, misalnya ketika Anda melihat darah atau ketika mata Anda diperiksa, sistem saraf Anda secara spontan bertindak seperti ketika Anda sedang berbaring, padahal Anda sedang duduk atau berdiri.