In terms of cognitive function, intelligence and cognitive deficits are common amongst youths with conduct disorder, particularly those with early-onset and have intelligence quotients (IQ) one standard deviation below the mean[27] and severe deficits in verbal reasoning and executive function.[28] Executive function difficulties may manifest in terms of one's ability to shift between tasks, plan as well as organize, and also inhibit a prepotent response. These findings hold true even after taking into account other variables such as socioeconomic status (SES), and education. However, IQ and executive function deficits are only one piece of the puzzle, and the magnitude of their influence is increased during transactional processes with environmental factors.[29]