hyperkinesis vs outburst

hyperkinesis

noun
  • Abnormally increased and sometimes uncontrollable activity or muscular movements. 

  • A condition especially of childhood characterized by hyperactivity. 

outburst

noun
  • a sudden, often violent expression of emotion or activity. 

verb
  • To burst out. 

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