Here I will mention two authors who try to explain the causes of this disorder. According to Grace, some possible reasons causing ADHD are related to the genetics of the family generation and the child's brain may have been exposed to toxins during pregnancy (Grace, 2011). According to the CDC, researchers believe that, similar to many other disorders, ADHD is likely caused by a combination of factors, such as genetics and environmental factors; researchers are also studying brain injury and nutrition (CDC,