What is infantile behavior in Brave New World?

Infantile behavior is something the masses are taught to exemplify since childhood. As adults they (mostly Betas) are encouraged to have sexual relations with multiple partners. They are encouraged to spend their free time using a drug called Soma and satisfy their primal desires. Responsibility to one another is discouraged. Bernard (an alpha) is repeatedly told by his superiors to stop his intellectual debates and participate in more infantile behavior.