Causes of ADHD
The exact cause of the development of ADHD is not known, but according to the ADHD familial genetic studies of the National Institute of Mental Health (NIMH), occurrences of ADHD developing in children is related to genetics and abnormalities with neurotransmitters. A child with ADHD siblings is 300-500 percent more likely to have this disorder and a child diagnosed with this disorder is four times as likely to have ADHD diagnosed relative. This suggests that ADHD is hereditary.
It has also been observed that people suffering from ADHD have abnormalities regarding their neurotransmitters specifically the Dopamine, which is responsible in controlling movements, assists in concentration, and regulates memory, and attention-seeking behavior. ADHD cases present low dopamine levels in the brain which is manifested by a child with low attention span and uncontrollable restlessness. In some cases, entire parts of the brain do not function as well compared to the same brain part in people who do not have this condition. Parts of the brain that are abnormally smaller are also observed to be present in some people with ADHD.
Another abnormality found in other patients is a mutated version of the DRD4 gene, which is involved in receiving signals carried between brain nerves. However, in some cases, genetics do not play a part in the development of ADHD. Some people with ADHD even have normally functioning brains that aren't smaller, which is the case in many ADHD individuals. Whatever the exact causes for ADHD are, they always cause the condition to develop during childhood. It may not be obvious for some children, but they will eventually be diagnosed with the condition once the symptoms start to become more and more apparent.