Discordance in psychotic illness across related individuals can be traced to differential exposure to trauma. The association between trauma and psychosis is apparent across different levels of illness and vulnerability to psychotic disorder, suggesting true association rather than reporting bias, reverse causality, or passive gene-environment correlation. Positive psychotic symptoms in vulnerable individuals may arise as a consequence of the level and frequency of exposure to abuse rather than neglect, suggesting symptom-specific and exposure-specific underlying mechanisms.
Childhood Trauma and Psychosis: A Case-Control and Case-Sibling Comparison Across Different Levels of Genetic Liability, Psychopathology, and Type of Trauma (kun abstract)
Am J Psychiatry, December 01, 2011