flashback vs subconscience

flashback

noun
  • A vivid mental image of a past trauma or other sensation that the trauma is happening in the present, especially one that recurs. 

  • A dramatic device in which an earlier event is inserted into the normal chronological flow of a narrative. 

  • The condition of the flame propagating down the hose of an oxy-fuel welding system. 

  • A query that operates against data from an earlier time, before it was changed. 

  • A similar recurrence of the effects of a hallucinogenic drug. 

verb
  • To undergo a flashback; to experience a vivid mental image from the past. 

subconscience

noun
  • Synonym of subconscious 

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