Traumatic brain injury and secondary attention-deficit/hyperactivity disorder in children and adolescents: The effect of reward on inhibitory control

Abstract

Poor inhibitory control and abnormalities in responding to rewards are characteristic of the developmental or primary form of attention-deficit/hyperactivity disorder (P-ADHD). A secondary form of ADHD (S-ADHD) may occur as a consequence of childhood traumatic brain injury (TBI), but the similarities and differences between these two forms of ADHD have not been well characterized. To address these issues, we studied two inhibitory control tasks under different reward conditions in four groups of children and adolescents: TBI who did not exhibit S-ADHD, TBI who did exhibit S-ADHD, P-ADHD, and healthy controls. Participants with TBI exhibited poor cancellation inhibition relative to controls. Although reward facilitated both cancellation and restraint inhibition similarly across groups, poor performance persisted in the P-ADHD group, and participants with S-ADHD exhibited a selective deficit in cancellation inhibition.

Keywords:

• Traumatic brain injury
• Attention-deficit/hyperactivity disorder
• Inhibitory control
• Rewards
• Development

Acknowledgments

Funding was provided by the Ontario Neurotrauma Foundation to Katia J. Sinopoli (2007-ABI-PHD-565, The Regulation of Thoughts and Actions in Children Following Traumatic Brain Injury). This research was also supported by an NIH (National Institutes of Health) 1RO1 grant to Keith O. Yeates and Maureen Dennis (HD048946-01A2, Social Outcomes in Pediatric Traumatic Brain Injury). We thank Shirley Chen for her help with the stop signal task and Renee Farrell and Alexandra Basile for their help with scoring and coding of demographic and questionnaire information.