The Emanuel Miller memorial lecture 1987. Childhood markers for adult disorders.

The paper is concerned with examining some indices, measured in childhood, that may be considered to be "vulnerability" or "genetic" markers for later adult disorder. The disorders of prime interest in this instance are schizophrenia and criminality. The source of data for the paper is a longitudinal study carried out in Mauritius, which started in 1972 with the examination of a total population of 3-yr-olds. While these subjects are not yet at an age when a sufficient number have developed schizophrenia to allow definitive statements to be made, sufficient data are available to indicate that indices employed as markers at age 3 predict later patterns of behaviour that are in line with studies in the literature as being characteristic of those who later become schizophrenic. The age 3 index which is employed is hyper- or hypo-activity of the electrodermal system. Later work has made particular use of smooth pursuit eye-movement, which has become a particularly strong candidate as a genetic marker for schizophrenia. Also reported is material that suggests that electrodermal activity may also be used to predict later delinquent patterns of behaviour.