Ever notice that classic movie scene where a character, overwhelmed by a situation, heads to the sink, splashes cold water on their face, and suddenly feels better? Well, it’s not magic – it’s science! This phenomenon can be attributed to the activation of the Mammalian Dive Reflex, an evolutionary adaptive response exhibited by mammals, including humans, when exposed to cold water. The reflex induces physiological changes, such as bradycardia (a decrease in heart rate), peripheral vasoconstriction (reduced blood flow to extremities), and alterations in respiratory patterns. These responses collectively engage the parasympathetic nervous system, promoting a state of physiological calmness. Consequently, individuals experiencing panic or anxiety may find relief through methods like splashing cold water on their face, taking brief ice-cold showers, or applying ice to their face while momentarily holding their breath, as these actions can trigger the Mammalian Dive Reflex.
Here’s a quick video explaning this reflex: