The vast majority of people have an ongoing conversation with themselves, an inner voice, that plays an important role in their daily lives. But between 5-10 per cent of the population do not have the same experience of an inner voice, and they find it more difficult to perform certain verbal memory...
Ooh, I don't really do that. I just tried it and it kind of works, but I think I'm much better with impressions in my real voice. I'd have to practice more.