Where is the “attention deficit” in ADHD? Perspectives from cognitive neuroscience and recommendations for future research

The suggestion that individuals with attention deficit hyperactivity disorder (ADHD) suffer from a subtle neurological dysfunction has existed throughout the history of modern clinical observations. However, after 100 years of observation and research, the identity of the primary mechanism(s) underlying this childhood disorder has yet to be conclusively resolved, as illustrated by the variety of neuropsychological theories covered in this edition. Whereas behavioral observations of “inattention” reliably distinguish children with ADHD from non-ADHD children (1), determination of whether inattention is a cognitive hallmark that identifies ADHD children from their non-ADHD counterparts has been more elusive. Clarification of this issue would allow for the development of more complete and accurate theoretical models of ADHD, aide in the etiological determination of the disorder, and inform cognitive neuroscience of the structure of attentional processes in normal and abnormal development. Clinically, such information would allow for more objective diagnostic procedures, earlier detection, and targeted therapies for rehabilitation.