Related Experiment Video
Updated: Apr 5, 2026
Training Rats to Voluntarily Dive Underwater: Investigations of the Mammalian Diving Response
Published on: November 12, 2014
Diving into the Ice Bucket Challenge: Intraparenchymal Hemorrhage and the Mammalian Diving Reflex
Kathleen McKee1, Sarah Nelson1, Ayush Batra2
1Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA ; Department of Neurology, Massachusetts General Hospital, Boston, MA, USA ; Harvard Medical School, Boston, MA, USA ; both the authors contributed equally to this study.
Abstract:
Triggered by facial exposure to cold water and apnea, the mammalian diving reflex consists of bradycardia and peripheral arteriolar vasoconstriction leading to an increase in central arterial pressure. It has been previously associated with ischemic stroke but not definitively with intracerebral hemorrhage. We present a case of intracerebral hemorrhage occurring in a woman with poorly controlled hypertension following her participation in the amyotrophic lateral sclerosis fund-raising "Ice Bucket Challenge," in which ice-cold water was poured on her head. We suspect that facial exposure to ice-cold water triggered the diving reflex, causing a hypertensive surge and ultimately the intracerebral hemorrhage.
