What is another word for getting into head?
Pronunciation: [ɡˌɛtɪŋ ˌɪntʊ hˈɛd] (IPA) 
The phrase "getting into head" is a common expression that typically refers to when someone is able to influence or manipulate the thoughts and beliefs of another person. Synonyms for this phrase might include "psychological manipulation," "mind control," "brainwashing," or "thought coercion." Other related phrases might include "getting inside someone's mind," "manipulating someone's thoughts," or "playing mind games." These phrases can all be used to describe a situation where someone is attempting to influence another person's thought processes, often in an effort to gain power or control over them. While these tactics can sometimes be used for positive purposes, they may also be employed for less ethical or even sinister goals.
