The two tests used are the Attention-Perception Test and the Gibson Spiral Maze Test. The 144 subjects ranged in age from 12 to 21 years, and all were either from centers under the administration of the juvenile court or the provincial prison of Granada, Spain. The control group consisted of 218 schoolchildren from four schools located in areas of different socioeconomic status. The results of the study showed that impulsivity and attention perception appear to be complementary traits which provide information useful for criminological prognosis. 11 tables, 18 references, 2 figures. (Author abstract modified)