Degeneration and regeneration of motor neurons in psychotic patients

The pattern of distribution of intramuscular nerve twigs was studied in muscle biopsies of peroneus brevis muscle from 62 schizophrenic and affective psychotic patients, and 8 normal control volunteers. Using methylene blue staining, the incidence of abnormally increased collateral branching was significantly greater in the patient population compared with normal controls. Paranoid psychotic patients had significantly higher values for branching than did non-paranoid schizophrenics. Abnormal branching was also correlated with excessive percentages of small angular muscle fibers. There was a significant relationship between increased branching and a positive family history of psychosis. The findings are suggestive of a process of neuronal degeneration followed by compensatory regeneration in some psychotic patients.