Impulsivity and negative priming: evidence for diminished cognitive inhibition in impulsive children.

This study addresses the relationship between impulsivity and lack of inhibition. Inhibition was measured both by the interference score and by the negative priming effect in a Stroop colour-word paradigm. The negative priming effect in this paradigm is defined by slower naming of a target colour if this colour was the distractor in the immediately preceding trial. For the study, a total of 210 school children were selected. These were children rated high or low by their teachers for either social or cognitive impulsivity. A reduced negative priming effect showed up with social type but not with cognitive type impulsive children. No differences were found regarding the Stroop interference score. The divergence between negative priming and interference as a measure of inhibition was discussed. Overall, the findings corroborate the distinction between a cognitive and a social dimension of impulsivity.