Didactics is a field of pedagogy that deals with theories, ideas, principles and instructions that answer the questions of what and how to teach.
Neurolinguistics The interdisciplina
Pedagogy is the science and art of education. It is related to how the teacher guides the teaching and learning process facilitating the acquisition and improvement of skills.
Psychology of language is the study of the psychological and neurobiological factors that enable humans to acquire, use, and understand language
Psycholinguistics = It is related with the theory of how to learn a language.
Science is the pursuit and application of knowledge and understanding of the natural and social world following a systematic methodology based on evidence.
Sociolinguistic = It is the study of the language but used in society.