Originally posted by GerryL I'm guessing he actually used less lights than what you would normally think.
Reflectors would most likely supplement the lesser number of lights.
The hair in particular has a circular highlight which you won't usually get with just a light from above as it would also highlight the upper portion (peak) of the hair.
Look at the reflections and shadows. There are 5 reflections on the hair. 2 from each side, and one overhead.
Reflectors aren't going to give you those hard specular reflections on the hair, and the hard (almost blown out) light on the sides of the face.
For the higher set of lights, they are only giving the hair light that you see at 10 and 2 o'clock.
The hair reflections at the base of her hair are the same ones that are lighting her neck and the sides of her face. You can tell that they are behind her because the light doesn't reach around to her cheeks. You can see the line of shadow (especially on her right cheek, but it is there on both cheeks) that show that the overhead light is lighting the front of her face and the rim lights are lighting the sides. Also, the fact that the light doesn't wrap around indicates that the light is pretty hard/small.
For the front/overhead light, all the hair isn't lit up, because of the angle of the light. If it were more overhead, then you would see the reflection at the peak of the hair. It doesn't need to be a circular or ring light to make that ring shaped reflection in her hair.