Sneezing is a reflex action controlled by the medulla in the brain.打喷嚏是由大脑髓质控制的反射动作。At birth, an infant can perform only simple reflex actions and behaviours.刚出生的婴儿只会做出简单的反射动作和行为。In a reflex, the effector muscle acts before your brain is able to think.在做反射动作时，效应肌肉在大脑意识之前就做出反应。