PHY3171 Lecture 15: L15 Dive response
Document Summary
Apnea: prevents aspiration of water (wet drowning) Peripheral vasoconstriction: redistributes blood flow from non-essential to essential organs (allows energy preservation for heart and brain) Bradycardia (decreased heart rate): helps to balance vasoconstriction, reduces energy consumption of heart. Temperature, presence of water + apnea: effects of these are present in 15-degree immersion. Face has receptor rich areas, innervated by trigeminal nerve originates from pons + medulla. Nerves branches receive input from changes in temperature + touch. Apnea voluntary or involuntary: voluntary = cerebral cortex. Water immersion temperature and touch/pressure: trigeminal nerve, first thing that happens when you put your face in the water = inhibition of respiratory muscle inhibition diaphragm in order to hold your breath. Respiratory centre also has effect on cardiovascular centre: cardiovascular centre. Sympathetic activity to peripheral organs causing vasoconstriction: tpr map. First thing that happens when you put your face in the water = inhibition of respiratory muscle inhibition diaphragm in order to hold your breath.