I believe there is a correlation between a person’s vocal language and their body language. Many people talk with their hands. This means that they use their hands in motion while they’re speaking. Some people even believe that they could not speak if they were sitting on their hands or they could not move their hands. I think body language goes hand in hand with the vocal language.
For instance, when a person is shaking their head yes to indicate an affirmative answer they may also say the word yes. So these gestures mean the same thing. If a person was shaking their head (while gesturing no)but saying the word 'yes', the other person would be confused.