Daydreaming can also be a form of intrapersonal communication

Intrapersonal communication takes place before, during, and after an interaction. For example, you wanting to go out with friends is a thought before an interaction. While you’re out you think about what you’re going to eat. After, you reminisce about the day you had with your friends.

Intrapersonal communication can simply be thinking about a text message before you send it.