What did Vygotsky called the use of language for self regulation?

Vygotsky called the use of language for self-regulation private speech.

He believed that children initially use language primarily for communication with others, but as they develop, they start using language to regulate their own thoughts and actions. This internalized speech, or private speech, helps children plan, solve problems, and control their behavior.

Vygotsky saw private speech as a crucial stage in cognitive development, a stepping stone towards more mature forms of self-regulation.