Automated testing of reaction time and its association with lead in children.

Following Needleman et al.'s (1979) report of a correlation between tooth lead estimates in children and reaction time as measured by Rodnick and Shakow's (1940) delayed reaction time paradigm, a version of the procedure with two delay periods of 3 s and 12 s was developed for automated presentation and scoring on a VIC-20 microcomputer. Data are presented from a study of 300 children aged 6-14 years. Mean reaction time over six trials for each delay period related in a curvilinear fashion with age, but no relationships were found with sex or intelligence. Age-adjusted reaction time related significantly with blood-lead levels, but accounted for only about 1 per cent of the variance. The effect was mainly observed in younger (6-10 years) children in whom higher lead was associated with slower reaction time.