fucked in the head vs shit-for-brains

fucked in the head

adj

  • Not quite right mentally: perverted, stupid, or mentally ill. 

shit-for-brains

adj

  • Extremely stupid. 

noun

  • An extremely stupid person. 

How often have the words fucked in the head and shit-for-brains occurred in a corpus of books? (source: Google Ngram Viewer )