Infants’ first year development and familial liability of attention deficit hyperactivity disorder

Previous literature has demonstrated high heritability in Attention Deficit Hyperactivity Disorder (ADHD) and identified some early risk factors in later development of ADHD, including language ability, motor skills and temperament. Emerging evidence has further suggested the possible link between ADHD and poor cognitive functioning and sensory processing. However, little research has done on the relationship between familial ADHD liability and the expression of those early risk factors during infancy. This study explored how familial ADHD liability associated with infants’ behaviours at their first year of life. Infants were categorized into ADHD and control group based on their parental history of ADHD. Standardized assessment and parental reports were used to examine infants’ cognitive functioning, sensory processing, communication, motor ability and temperament. Results indicated that there were no significant differences in behavioural outcomes between infants with and without familial ADHD liability at both 6 and 12 months of age. These results suggested that familial history of ADHD was not a good predictor to detect early differences of cognitive functioning, sensory processing, communication, motor ability and temperament in infancy. Future research is necessary to fully understand the manifestation and pathogenesis of ADHD.