Impulsivity and the multi-impulsive personality disorder

The purpose of this study was to test the hypothesis that impulsiveness is positively related to the total number of categories of distinct impulse control incidents. That is, high impulsive individuals are more likely to be involved in more separate types of impulsive acts than low impulsive subjects. This is an extension and replication of research done by Kennedy and Grubin [(1990) British Journal of Addiction, 85, 639-643] on the multi-impulsive personality disorder [Lacey & Evans (1986) British Journal of Addiction, 81, 641-649]. The current study extends past research by: (1) studying inmates from a general prison population; (2) controlling for IQ and educational achievement; (3) the inclusion of impulsive fire-setting as a disorder; and (4) using impulsiveness subtraits as well as a global measure of general impulsiveness. Our results indicate that an impulsiveness subtrait, motor impulsiveness, was significantly related to the number of different types of impulse control incidents an individual displays. Global impulsiveness was not related to these incidents. The number of impulse control disorders an inmate displayed was not related to age, duration of present sentence (years), educational achievement or intellect. Categories of impulsive incidents used in this study were independent except for other drug abuse and sedative dependence. These results are consistent with Kennedy and Grubin's (1990) results and support Lacey and Evans' (1986) proposed multi-impulsive personality disorder.