desensitize vs immobilize

desensitize

verb
  • To cause to become less sensitive or insensitive. 

immobilize

verb
  • To render motionless; to stop moving or stop from moving. 

  • To modify a surface such that things will not stick to it 

  • To tie up a capital: make a capital investment that makes that capital unavailable. 

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