It’s the muscle that pulls them down.” He shook his head and
looked at me again. “Ooh! You’ve got a fantastic thirty-nine.
That’s one of the best I’ve ever seen. It’s genetic. There should
be other members of your family who have this heretofore
unknown talent. You’ve got it, you’ve got it.” He laughed again.
“You’re in a position to flash it at people. See, you should try
that in a singles bar!”
Ekman then began to layer one action unit on top of
another, in order to compose the more complicated facial
expressions that we generally recognize as emotions. Happiness,
for instance, is essentially A.U. six and twelve — contracting
the muscles that raise the cheek (orbicularis oculi, pars
orbitalis) in combination with the zygomatic major, which pulls
up the corners of the lips. Fear is A.U. one, two, and four, or,
more fully, one, two, four, five, and twenty, with or without
action units twenty-five, twenty-six, or twenty-seven. That is:
the inner brow raiser (frontalis, pars medialis) plus the outer
brow raiser (frontalis, pars lateralis) plus the brow-lowering
depressor supercilii plus the levator palpebrae superioris (which
raises the upper lid) plus the risorius (which stretches the lips)
plus the parting of the lips (depressor labii) plus the masseter
(which drops the jaw). Disgust? That’s mostly A.U. nine, the