P&G BeautyArticles & NewsHomeP&G Announces Reusable Shampoo BottlesThe bottles span across a line of its brands such as Pantene and Head & Shoulders.HomeHair Health Starts With the Scalp: Insights from Two P&G Head & Shoulders ExpertsHair care scientists scratched their heads for some time before they could put their finger on the primary causes of dandruff. Now, with the flakes brushed away, they are seeing the scalp in a new light. Two Procter & Gamble scientists, James Schwartz, Ph.D., and Rolanda Wilkerson, Ph.D., both with the Head & Shoulders brand, explain how in this exclusive interview.