key up vs motivate

key up

verb
  • To raise the intensity, excitement, tension, etc., of. 

  • To produce nervous tension in. 

  • To raise the pitch of. 

  • To raise (the whole ring of an arch) off its centering, by driving in the keystone forcibly. 

motivate

verb
  • To provide someone with an incentive to do something; to encourage. 

  • To animate; to propel; to cause to take action 

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