Part 1 of Essay
There are many factors, which determine ADHD. This paper will show the different symptoms of ADHD and how the brain effects this disorder. It is especially difficult to establish this diagnosis in children younger than age four or five years because their characteristics behavior is much more variable than that of older ....

Part 2 of Essay
.... In order to be diagnosed with ADHD some symptoms that cause impairment must have been present before seven years of age. Also some impairment from the symptoms must be present in at least two settings such as work, home or school. It is very unusual for an individual to display the same level of dysfunction in all settings or within the dame setting at all times. There must also be clear evidence of interference with developmentally appropriate social, academic, or occupational functioning (First, 1994, p.78). ....