What kind of experience is "brain pumping"

What does "brain tonic" mean here? I think it means doing something out of line that should not be done. Sometimes "brain pumping" is really something that you feel very cool, but it is boring and annoying to others, so sometimes "brain pumping" still makes people feel cute, but sometimes it is just casual.

Once a teacher was in class, because it was always possible to go to the toilet without saying hello to the teacher, but this was the first time the teacher taught us, so I went to the toilet without saying hello to the teacher, and then the teacher told me in class that I wanted to show him off, and then my roommate informed me that the teacher was angry with me by mobile phone, and then I was so angry that I didn't call. Can you blame me? Didn't the teacher see me?

Who would want to show off you? Then I entered the classroom from the front door, and the teacher didn't start giving me a lecture. Then I didn't know how to be "brain-dead", so I bowed to the teacher and said, "I'm sorry, teacher, I shouldn't go to the toilet without saying hello." Then the whole class was silent, and then there were bursts of laughter.

How can I put it? Once a person "fills his brain", he will make actions different from ordinary people. These actions are beyond the understanding of ordinary people, even mocking. Then there are several examples, such as criticizing that person in front of other people's boyfriends, saying bad things about her, and being particularly close to her. This is a kind of "brain tonic" performance. In class, the teacher asks questions and then