ADD is situational: in the same individual its expression may vary greatly from one circumstance to another. There are certain classes, for example, in which the ADD child may perform remarkably well, while in others she is scattered, unproductive, and perhaps disruptive. Teachers may conclude that the child is wilfully deciding when, or when not, to buckle down and work diligently. Many children with ADD are subjected to overt disapproval and public shaming in the classroom for behaviours they do not consciously choose. These children are not purposively inattentive or disobedient. There are emotional and neurophysiological forces at play that do the actual deciding for them. We shall examine them in due course.
The second nearly ubiquitous characteristic of ADD is impulsiveness of word or deed, with poorly-controlled emotional reactivity. The adult or child with ADD can barely restrain himself from interrupting others, finds it a torture awaiting his turn in all manner of activities, and will often act or speak impulsively as if aforethought had never been invented. The consequences are predictably negative. One is forever trying to shut the barn door after the horse has bolted. "I want to control myself," a 33-year old man said at his first visit to my office, "but my mind won’t let me." The impulsiveness may express itself as impulse buying, the purchase of unneeded items on a sudden whim without regard for cost or consequence. "Impulse buying?", another man exclaimed during our first interview. "If I had the money I would impulse buy the whole world."
Hyperactivity is the third salient characteristic of ADD. Classically it is expressed by trouble keeping physically still, but it may also be present in forms not readily obvious to the observer. Some fidgetiness will likely be apparent--toes or fingers tapping, thighs pumping, nails being chewed, teeth biting the inside of the mouth. The hyperactivity may also take the form of excessive talking. In a minority of cases, especially in girls, hyperactivity may be absent altogether. They may go through school inattentive and absent minded but, as they cause no trouble, they are "passed through" from grade to grade. While the finding of hyperactivity is not required for the diagnosis of ADD, it can be quite dramatic for some patients. "The only thing that ever slowed me down was the police siren when I was caught speeding, " said a twenty-seven year old