Several authors have noted that there are no reported cases of people with schizophrenia who were born blind or who developed blindness shortly after birth, suggesting that congenital or early (C/E) blindness may serve as a protective factor against schizophrenia.

Protective effects of blindness may not exist if other forms of severe sensory loss are present.

http://journal.frontiersin....psyg.2012.00624/full