I am hoping this image will illustrate what I mean by highlights in the hair. I don't mean the shine on the hair, I mean the subtle differences in colour between the different strands that catch the light. This is Adorana's Gianco hair on M4. I used two different texture maps in the hair shader - one darker, one lighter. Both are fur textures created with Genetica. The darker one is  used for the root and tip, but I use an hsv node to turn down the value for the root to .4. The lighter, brighter texture map is used for specularity.

Poser 11 Pro, Windows 10

Auxiliary Apps: Blender 2.79, Vue Complete 2016, Genetica 4 Pro, Gliftex 11 Pro, CorelDraw Suite X6, Comic Life 2, Project Dogwaffle Howler 8, Stitch Witch