Pain insensitivity in the relatives of schizophrenia patients.

The psychiatric literature contains anecdotal reports of diminished pain sensitivity in schizophrenia that date back to Kraepelin. Yet, the phenomenon of pain insensitivity in schizophrenia remains largely unstudied. For example, it is not clear if pain insensitivity is a consequence of the illness or if it is also present in the well relatives of schizophrenia patients. To explore this issue, we examined pain thresholds and pain tolerances in healthy young adults. Compared with controls with no family history of psychopathology (n=21), participants with a family history of schizophrenia (n=32) showed elevated pain thresholds and pain tolerances to finger pressure. Pain insensitivity was also significantly correlated with elevated scores on measures of self-referential thinking, magical ideation, and perceptual disturbances. Finally, a sizeable minority (19%) of well relatives of schizophrenia patients showed extreme pain insensitivity compared to other participants. The pattern of findings suggests that pain insensitivity may warrant further exploration as a potential marker of underlying liability to psychosis.