Raz Gross, M.D., M.P.H. (Young Investigator 2004) of Columbia University, proposes to follow up on results from his prior NARSAD-funded project that showed exposure of the brain to ionizing (x-ray) radiation early in childhood (before 5 years of age) is associated with an increased risk of schizophrenia later in life.

The study drew upon a landmark Israeli study of children 43-55 years ago who were exposed to x-rays of the head during childhood for the treatment of a scalp ringworm infection. Preliminary findings suggested that those exposed early (<5) had more than a two-fold, statistically significant increase in schizophrenia risk when compared with unexposed siblings. Increased schizophrenia risk also correlated with a higher x-ray dose exposure. Schizophrenia determination was done by a linkage of the cohort population to a national psychiatric case registry.

In the new project, Dr. Gross is seeking to obtain a better diagnosis of schizophrenia, by means of chart diagnosis; and to delineate the relationship between early exposure, premorbid cognitive function, and schizophrenia, by using IQ data at adolescence (age 16-17), available for this cohort from the Israeli Draft Board registry. Results may contribute to a better identification of the vulnerable periods in brain development that lead to schizophrenia.