To those around him, Nash had lost his motivation to complete his dissertation and, later, to be a teacher.
In reality, Nash was preoccupied with his delusions.
According to the book, Nash hears voices that tell him what to do, but he does not have visual hallucinations.
Since this paper is based on the movie, this paper will use the visual hallucinations as a symptom of Nash's illness.
The movie paints a somewhat optimistic picture of Nash's life with schizophrenia.
He eventually is allowed to return to Princeton in a limited capacity and eventually wins the Nobel Prize.
This criteria describes Nash's ragged personal appearance, his work history, and the problems in his marriage.
DSM-IV also requires that these symptoms must be present for at least 6 months.
For John Nash, these symptoms lasted from at least when he was in graduate school, if not before, and continued for the rest of his life.
It is unclear exactly what causes schizophrenia, although it appears that a combination of genetic and environmental factors are involved (National Institute of Mental Health [NIMH], 2005).