enhanced vs heightened

enhanced

adj
  • Raised up, amplified. 

  • Having suffered the use of anabolic steroids or other performance-enhancing drugs. 

  • In a version or form that has been improved or made better than some other standard form. 

heightened

adj
  • increased in intensity or concentration; elevated, stepped-up 

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