Why does a baby’s hand
automatically close on your finger?

That reaction is called the grasp reflex. Everyone has reflexes, automatic nerve actions that the body makes without being directed by the brain. Has the doctor ever tapped your knee with a little rubber hammer, and did your leg kick without your telling it to? That’s a reflex, and it happened automatically.

Babies are born with some special reflexes, including the grasp reflex. The suck reflex is another one. We see it when a baby takes a pacifier. Babies typically lose the grasp reflex at about three months of age, and they lose the suck reflex at about four months.

—Patricia Landry, M.D.