body language vs emotion

body language

noun
  • Nonverbal communication by means of facial expressions, eye behavior, gestures, posture, and the like; often thought to be involuntary. 

  • Deliberate, usually culturally influenced, nonverbal communication using the body through facial expressions, gestures, dance, mime, etc. 

emotion

noun
  • A person's internal state of being and involuntary physiological response to an object or a situation, based on or tied to physical state and sensory data. 

  • A reaction by a non-human organism with behavioral and physiological elements similar to a person's response. 

How often have the words body language and emotion occurred in a corpus of books? (source: Google Ngram Viewer )