I had a girlfriend who had dated Paul Ekman, the man who developed the field of facial micro expressions. So I found out about the field.
Ekman had done work at U.C. Med school in San Francisco to use panels of viewers to look at videos of subjects facial and physical expressions to build a catalog of the expression's meanings.
For example when a person puts both hands behind his head and leans back he is saying: ‘I’m not listening’. When he is talking and covers his mouth, he is saying: ‘I don’t believe what I’m telling you’.
Ekman went further and explored micro-expressions. He became so convinced of his experimental reliability that he tried to apply his findings to other cultures…. Latin America. It didn’t work.
The CIA tried to use his techniques to detect lying. They couldn’t make it work. So Ekman went off to help the Soviets.
I never considered the field meaningful. Ekman had too many possible meanings for the physical expressions he studied.
Now I see that the world of digital geniuses are going to use facial expressions and body movements to improve language understanding in the computer world.
More nonsense as far as I can tell.