Attention-Deficit/Hyperactivity Disorder is a neurological condition that leads to difficulty controlling and halting ideas (inattention), movement (physical restlessness) and behaviour (impulsivity).
ADHD affects about 5% of children and follow-up studies have shown that symptoms persist into adulthood for more than half of these. A recent U.S. study estimates the prevalence rate of ADHD in the adult population at 4%. ADHD adults suffer above all from cognitive-attention problems (distractibility, mental restlessness), associated disorganization (e.g., procrastination: difficulty beginning and completing tasks, tendency to scatter one's attention, difficulty keeping track of time), and impulsivity. These are as much an impediment at work as in their private life. At times, ADHD adults also have difficulty modulating their emotional responses ("thin-skinned", "hypersensitive", "short-fused"). Often, these individuals will have learned to deal with their physical restlessness by channelling it into their work or through sports. Some will "self-medicate" by taking over-the-counter psychostimulants (e.g., caffeine, nicotine) or illicit drugs obtained on the street (e.g., cannabis, cocaine).
On account of these symptoms and their impact, many people with ADHD also suffer from poor self-esteem and a chronic sense of under-achievement.