chemically imbalanced vs manic-depressive

chemically imbalanced

adj

  • Mentally ill. 

  • Used other than figuratively or idiomatically: see chemically, imbalanced. 

manic-depressive

adj

  • Exhibiting manic depression. 

noun

  • A person with manic depression. 

How often have the words chemically imbalanced and manic-depressive occurred in a corpus of books? (source: Google Ngram Viewer )