There are people who do not have internal monologue or “do not hear the voice” in their mind. I wonder what would be the reason/aspect/point of view from Dhamma.
If it’s not the proper forum, we can move it to Abhidhamma.
1. The first one is more related to vaci sankhara (vitakka/vicara.)
Before speaking or moving the body, we “talk to ourselves” about it, i.e., “the mind thinks about it” and even deliberate various aspects like “Should I say something?”, “Is it appropriate?” etc.
But how much one deliberates is relative. Some people think incessantly about whether to do something or say something. But there are others who just “go with the flow.”
That lady is in the second category. She does not even realize that she thinks before saying, writing, or doing things.
2. The second category is a more established “field of investigation.” See “Aphantasia.”
The opposite of aphantasia is phantasia or “to fantasize.” Again, some people spend hours fantasizing about various expectations or “reliving past events” by recalling those events. They have vivid images arising in their minds.
You can test your ability to make “imageries” in your mind. Close your eyes and try to imagine a red apple in your mind. Some can, and some cannot. Some people can go through past experiences in vivid detail (even with color).