The conditions causing the psychological condition, Attention Deficit Hyperactivity Disorder or ADHD has continued to become a puzzle to psychologists. Overtime, the symptoms for ADHD have undergone numerous diagnoses. Although the main cause of ADHD remains unknown, present evidences show that ADHD is genetically acquired (Lilly, 2007). ADHD is a mental disorder characterized by problems of hyperactivity and impulsiveness. According to the Diagnostic and Statistical Manual of Mental Disorders-IV, inattention and hyperactivity-impulsivity are either or both of the two syndromes associated with this psychological disorder (House, 2002).
ADHD is one of the most common mental disorders among children in the United States and it is believed that it affects 4 to 5 percent of the children in the country (Coile, 2004). ADHD often affects the school performance of the children. Because of the lack of attention and hyperactivity of children, it is difficult for them to concentrate on learning or educational activities (House, 2002). One of the speculated roots of ADHD is through heredity and genetics. Researches presented that ADHD runs in families.
According to the Pediatric Annals, there is a 25 percent chance that the child of an adult with ADHD will also acquire the disease (Lilly, 2007). At present, since there is insufficient evidence on the real and exact cause of ADHD. Most researches consider the genetic explanation of ADHD as the most valid. It is believed that a particular gene is passed on from parents to children; this may be the inherent cause of ADHD. This can be well explained in identical twins. If one of the twins has ADHD, there is a greater risk that other will have it too (Driscoll, 2007).
Researches firmly suggest that ADHD occurs in cluster within families. ADHD occurs in biological relatives of children or adults with the disorder, implying the strong hereditary cause of the disorder. An ADHD twin studies found out that identical twins are most likely to manifest symptoms of ADHD, and this finding is consistent in all studies conducted (Joseph, 2006). One of the comprehensive reviews in the twin studies is made by Jay Joseph where he examined the continued misinterpretation on the findings of the twin studies.
He firmly believed that the similarities manifested by the twins are not presenting the possible genetic influences on ADHD but this may lie on the environmental factors experienced by the twins (Southhall, 2007). The twin studies are crucial theoretical assumptions. Some researchers claim that the studies are not supported by sufficient evidences. The study merely focused on identical twins, but there are fraternal twins and considered that the environmental factors are equal, there are changes in the findings.
Since the evidences is deeply anchored on identical twins who are treated more alike and spend more time together and has a greater tendency to experience confusion and closeness, thus, in a controlled environment, it is expect that the identical twins will correlate higher than the fraternal twins on ADHD measures (Joseph, 2006). ADHD twin studies are based on unsupported theoretical assumption and offer only a possible genetic influence on the symptoms of ADHD.
These studies recorded are based more on the psychological bond, more similar treatment and same environment experienced by identical twins than fraternal twins (Joseph, 2002). Another method of study used to discover the roots of ADHS is the adoption study. The difference of this approach on the twin studies is that, it is able to disentangle genetic and environmental influences on psychiatric disorders due to the genes that came from one family and was raised in the environment of another.
The rules of hereditary and environmental influences or the nurture and nature influences are relevant in this study of ADHD causes (Joseph, 2002). In this approach, participants are obtained from families with adopted children and families with their biological children, who both have ADHD and same type of families without the psychological disorder. However the research is proven to have a flaw; it is unable to consider the biological parents and relatives of the adopted children. This may contain pertinent information on the genetic influence of ADHD.
Therefore, the researchers were not able to make a definite comparison on the foster and biological families of the adopted children. Another flaw of the research is that hyperactivity of the parents is solely based on recollections of the parents if they experienced symptoms of ADHD when they were young. This method and data are unreliable for the having the possibility of giving false accounts (Joseph, 2002). The fundamental assumption of the adoption studies is that ADHD is more prevalent in biological families than in families with adopted children.
The studies found higher rates of hyperactivity in children and their biological parents than children with adoptive parents (Joseph, 2002). It is reasonable to dismiss the conclusions of the adoption studies since it did not perform blind diagnoses and introduced a genetically-biased research with conclusions favoring genetics. The control group is unable to serve its purpose if the researchers know the participants related to the cases and which belongs to the control group (Joseph, 2002).
Now, psychiatric geneticists see children inheriting a predisposition that will eventually develop into ADHD in the presence of unknown environmental factors which might include viruses and toxins (Joseph, 2002). Though the genetic influences are believed to be the most valid cause of Attention Deficit Hyperactivity Disorder (ADHD), they seem to only give possible genetic assumptions and add to the incomplete puzzle of the real cause of ADHD, as the root cause of the psychological disorder targeting most of our children is still unknown.