Lama Ole’s answer:
In Buddhism, one speaks of four different kinds of madness:
The first kind arises if one used a lot of drugs or alcohol in former lives. Then in this life, one will be born without enough neurological connections in the brain—so the “machine” works with some defects.
Second, there are malfunctions that result from using a lot of drugs or alcohol in this life.
The third type appears when a person has lived so unhappily, brought so little joy into his life, and let himself go so much that he is no longer protected by the good impressions in the mind of a healthy person. Then various strange energies can come in and work inside a person. This is called schizophrenia.
And the fourth possibility is that a person has allowed so many negative and disturbing impressions to accumulate in the store consciousness that every time the mind comes to these points, it can’t stand it and tries to escape into something else. These would be states of paranoia.
After death, problems and disturbances associated with the body fall away, and one has new possibilities again. On the other hand, when one has built up very strong disturbing energies within oneself, then these also go along into the next life.