Ray Birdwhistell (1918 – 1994) determined that as adults, 7% of our communications are in the words we speak, 23% is in voice inflection, and 70% is in our facial expression and body language.
Birdwhistell pointed out that "human gestures differ from those of other animals in that they are polysemic, that they can be interpreted to have many different meanings depending on the communicative context in which they are produced". And, he "resisted the idea that "body language" could be deciphered in some absolute fashion". He also indicated that "every body movement must be interpreted broadly and in conjunction with every other element in communication"[50]
Voice changes, eye movement, hand movement, body position, . . . They all add to information on what we are thinking.