ADHD has had many different names since the early 1900s, many of which reflected the current thinking of the time. Before the disorder was officially recognized by the American Psychiatric Association (APA) as a mental disorder in the mid-1980s, ADHD was called minimal brain damage and minimal brain dysfunction.
Since then, the disorder has been renamed many times in the APA's Diagnostic and Statistic Manual of Mental Disorders (DSM). The first edition of the DSM called it “hyperactivity of childhood.” The second edition, published in 1968, changed the name to “hyperkinetic reaction of children.” In 1980, the third edition of the DSM renamed it “attention deficit disorder with or without hyperactivity.
So What's Taking So Long?
Given the dramatic advances in technology, you may be wondering how and why scientists could figure out how to send a man to the moon, but still not understand what causes a biological disorder that affects millions of children.
The easiest answer is that the human brain is a complicated labyrinth. Scientists now know that the primary symptom of childhood ADHD is an inability to self-regulate, or to control attention, temper, moods, and impulses.
The NIH conducted a landmark study in 1990 that showed there was reduced glucose uptake in the brains of children with ADHD compared with “normal” people. This study established a biological basis for ADHD by providing a measurable difference between the ADHD and non-ADHD brain. But scientists still don't understand where the difference comes from or exactly what it means.
With advances in technology, scientists are now able to explore the brain for abnormalities that could result in childhood ADHD. While past research focused almost exclusively on external factors like parental upbringing, environmental causes, and toxic culprits like sugar and lead, research today targets genetic, anatomical, functional, and chemical brain dysfunctions as potential causes of the disorder.