On the relation between IQ, impulsivity, and delinquency: remarks on the Lynam, Moffitt, and Stouthamer-Loeber (1993)...

A recent report by D. Lynam, M. Moffitt, & M. Stouthamer-Loeber (1993) examined the inverse relation between IQ and delinquency and concluded that the observed relation represents "an influence of compromised intelligence on delinquent behavior" (p. 193). Specifically, the role of impulsivity in understanding this relation was discounted. The author considers the conceptual, operational, and analytical bases of the Lynam et al. report and argues that their neurologically based view of "executive dysfunction" as underlying delinquency is selectively portrayed. It is further contended that IQ scores, used as their index of brain-behavior relations, are only remotely related to specifiable neurological functioning. The Lynam et al. conclusion that impulsivity cannot appreciably explain the relation between IQ and delinquency is shown to depend on the analytical approach used. Analyzed alternatively, impulsivity emerges as the more important predictor that can mediate the observed IQ and delinquency relation. Social policy implications of these differing interpretations are noted.