A child or adult with attention deficit disorder (ADHD) may be diagnosed with one of three sub-groups:
- ADHD-Combined Type means that the individual is hyperactive, inattentive, and impulsive
- ADHD-Hyperactive-Impulsive Type means that the individual is hyperactive and impulsive
- ADHD-Inattentive Type means that the individual is only inattentive.
It is not difficult to understand what behaviors go with being hyperactive or impulsive. But what does inattentive mean?
The guidelines listed in the Diagnostic and Statistical Manual of Mental Disorders-IV, used to establish whether a child or adult is inattentive, requires the clinician to identify at least six behaviors out of nine (see Inattentive ADHD in a Nutshell).
One of the nine behaviors listed refers to being distracted by external stimuli (sounds or visual stimuli). Another refers to difficulty sustaining attention. The remaining seven describe difficulties related to the concept of executive function — the ability to conceptualize a task, plan how to carry it out, and complete it in a timely way. (These problems can also be thought of as difficulties with organization and planning your time.) Thus, a child or adult who had difficulties with executive function alone could meet the criteria to be identified as having inattention.