Another characteristic manifestation of ADHD is excessive or developmentally inappropriate motor or vocal activity. Typical of this are pointless, excessive movements – running around, jumping, writhing, restlessness when seated, playing with hands, aimless doodling, etc. Hyperactivity in speech manifests itself through excessive bursts of speech, increased volume, frequent interruptions and sudden shouts. We may sometimes notice the child making odd sounds to accompany a given activity or loudly commentating on their current activity. Rapid speech may even lead to loss of breath.

Excessive activity is a typical behavior of almost all children with ADHD. Hyperactivity manifests itself during the first years of a child’s life, one conspicuous indicator is a constant movement of the hands, feet, lips or tongue.

Excessive, rapid, insufficiently coordinated movements lead to more frequent injuries. Children with ADHD are more likely to have disciplinary problems, most often however due to unintentional offences than any intentional violation of the rules. Their relationship towards adults is often without social constraints and they have difficulty submitting to adult authority. Children with ADHD are often not popular with their peers and can easily become isolated within a group.Some children with ADHD may have difficulties falling asleep.

For children with attention deficit disorder without hyperactivity (known as ADD or ADHD-PI or predominantly inattentive in the US) we may conversely notice hypoactivity. These children are very slow in their reactions, cumbersome and generally appear subdued or even apathetic. They are often wrongly labelled as lazy, despite merely being slower than their peers.