That change is incredibly subtle, which is why, when you look at other people, when you look at the person sitting next to you, you don't see their skin or their face changing color.
Ky ndryshim eshte tejmase i lehte dhe shpjegon pse kur shohim njerez te tjere, per shembull kur sheh  personin e ulur afer teje, nuk arrin te dallosh ndryshimin e ngjyres tek lekura e tyre.