7 citations,
December 2002 in “PubMed” The scalp has a natural speckled pattern of increased pigment around hair follicles, possibly linked to local hormone production.
19 citations,
July 2009 in “Clinical and Experimental Dermatology” The study found that long-term sun exposure does not significantly affect follicular plugs on the scalp, and the scalp's appearance is unique compared to other body parts.