Causes of ADHD

Despite much clinical research, the precise causes of ADHD are unknown. For parents who seek answers about their child’s behavior this can be extremely frustrating. Many theories exist about how ADHD develops. While some attribute ADHD to a poor upbringing, laziness, low intelligence, or exposure to too much television, this is most certainly not the case. Rather, ADHD is most likely caused by one or more biological, environmental or physiological factors.

Heredity is widely considered to be one of the primary causes of ADHD. Children who have ADHD are five times as likely to have a family member with it as well. Twin studies, in which researchers look for common traits between identical and non-identical twin pairs and compare their occurrence, provide good insight into the potential heritability of the disorder. Studies show that when one identical twin has ADHD the other twin has it 82 percent of the time. Conversely, in non-identical twins, if one has ADHD the other one has it 38 percent of the time. Because identical twins share 100 percent of their genetic material and non-identical twins share only 50 percent, the higher rates of ADHD between identical twins indicate a genetic component to the disorder.

Environmental factors are also suspected to be causes of ADHD. ADHD is more prevalent in children whose mothers used tobacco products or consumed alcohol during pregnancy. Exposure to lead paint has also been associated with some ADHD symptoms, particularly hyperactivity. These toxins negatively impact the development of brain tissue and may result in long-term behavioral effects.

What is certain is that children who have ADHD have brains that function differently and develop more slowly than other Causes of ADHDchildren. Specifically, the frontal lobe, which is responsible for executive functions such as planning, behavioral control, problem solving and decision-making, matures at a rate about three years slower than other children. Brain studies of children with ADHD have also shown a generally delayed maturation of the cerebral cortex, which could be one of the causes of ADHD.

Children may develop ADHD because of one of these factors or because of a combination of them. Whatever the case, ADHD is extremely common, impacting around 5 percent of children in the United States, and is highly treatable. So while the exact cause of the disorder remains a bit of a mystery, parents can take comfort in knowing that there are a myriad of treatments to help their child manage their symptoms at home and at school.

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