In Ancient Egypt common mourners taking part in funerary cortege were depicted making many different gestures.
These women could raise their arms as if they were praying to the gods the return of the dead.
Some times their hands appear over their heads as beating them in an evident show of despair.

Common mourners from the tomb of Ameneminet. XIX Dynasty. Photo http://www.osirisnet.net
The ancient Egyptian mourners also put their hands in front of their eyes, maybe in an intention of showing the human reflect of covering the eyes (and also the face) when crying.
The artist of Ancient Egypt found also the way of depicting the sadness movements of those women by drawing their hands holding their back of the neck, crossing their arms on their chests, kneeling and/or bending their bodies forwards.

The wife is kneeling and crying, Isis stands on the left and Nephtys on the right. Painting from the tomb of Samut in Assassif. XIX Dynasty. Photo: http://www.osirisnet.net
But those gestures were usual in common mourners. What about the two professional mourners in the role of Isis and Nephthys?
These two women shared with the formers ones many of these gestures, but not all of them.