Pret Badha Pisaach Badha as per astrology a modern logical approach on the combinations as given in classics,

 Psychological disorders like schizophrenia, bipolar, and other such spectrum disorders were perhaps mentioned as Grah Badha in scriptures and classical texts these factors were attributed to Grah's in the nomenclature terminology like Bhoot Grah, Pisach Grah. Before explaining the factor let's first understand what Grah is? One given definition is of one that grips or holds. So what would be the Bhoot or Pisach Grah this would definitely mean the Grah or planet that is malefic and one that has Moon ( mind) under a steadfast grip, This Bhoot Grah may have its accomplice Grah's ( malefic like Saturn, Rahu/Ketu/12th lord ) applying their grip on planets Mercury ( intellect) Jupiter ( Wisdom/higher intelligence and ability to think and remember). Mars though a malefic is related to factual but logical circumstances it would often trigger the circumstantial environment conditions due to build-up of negative emotions like aggression, frustration, and feeling of inequality in a violent or aggressive form which is called Unmaad or ( frenzy of emotions depicted through crazy behavior almost like insanity).Udyot Kar Jha sir please feel free to correct me if my line of thinking does not concur as per accepted norms of astrological classics.