Dr. Awkward (palindrome)
If we look at how communication works we find that words and phrases have a great influence on attention. They bring into the consciousness of the listener the concepts that are uttered. This is what meaning is – the concepts that a word or phrase can steer attention towards. This is what communication is – the sharing of attention by two (or more) brains on a sequence of concepts.
So it is not surprising that it is useful to talk to oneself. What we are doing when we self-talk is to steer our consciousness. In recent paper, Lupyan and Swingley look at how self-directed speech affects searching.
