Four studies were conducted to examine the manner in which cognitively impulsive and reflective children use private speech to control their behaviors. The first study was a naturalistic observation of a group of impulsive (N=8) and reflective (N=8) nursery school children, identified by the Matching Familiar Figures Test. The Impulsive and…

This study investigated whether the stimulant methylphenidate (Ritalin) would differentially affect performance on a test of cognitive style by hyperactive children. Subjects were 55 children, (ages 7 to 15) referred to the Learning Clinic at the Hospital for Sick Children, Toronto, Canada for hyperactivity and/or learning problems. A paired…