The sucking reflex appears between 0 and 3 months of age, and the infant will suck when something is placed in the infant’s mouth. It disappears on its own 3-4 months after birth and is gradually replaced by active feeding movements. However, during sleep and on some other occasions, infants still show spontaneous sucking movements for a period of time. A positive sucking reflex is indicative of the cerebral cortex if it is still present after 1 year of age. So, what are the tests for a positive sucking reflex? When the lips are gently scratched or tapped, there is an immediate contraction of the orbicularis oris muscle and the upper and lower lips pucker, causing a “sucking” action. Normal people do not have this reflex. 1.Time of appearance: 0-3 months old. 2.Characteristic: The infant will suck when something is put into the baby’s mouth. 6 weeks later, the breathing, sucking and swallowing reflexes are coordinated with each other and feeding will become more efficient. 3.Clinical manifestation: When the lips are gently scratched or tapped, the orbicularis oris muscle will contract immediately and the upper and lower lips will pucker, causing a “sucking” action. Normal people do not have this reflex. 4. Disappearance time: It will begin to disappear slowly after 3 months. Nowadays, medical science has borrowed the sucking reflex of comatose patients to turn “waste” into “treasure” and successfully put in the gastric tube.