This study examines two questions: (1) are the natural environmental contingencies under which reflective and impulsive children operate different? and (2) if so, which, if any of these differences, predict the nature of behavior change? Forty impulsive and reflective children and their mothers were observed while solving discrimination problems…

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…