ADHD Overview

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Rowdy, rambunctious, out-of-control children are nothing new, but when is a child's misbehavior something more than that? Attention Deficit Hyperactivity Disorder, usually referred to as ADHD, is a puzzling condition, a neurobehavioral disorder that's rather common but surrounded by myths and controversies that often obscure the facts. Many people deny that the condition even exists, attributing children's problems to laziness, a basic desire to act out, an unruly personality or simply too much sugar. But extensive research has shown that the condition is real, even if some of its characteristics, fundamental causes and treatment avenues remain topics of debate.

Practically every child and even some adults exhibit some of the behaviors associated with ADHD. However, for those who must deal with the disorder, it can be enormously frustrating and disruptive to everyday life. Although adults can also suffer from ADHD, it's commonly linked with children; 3 to 5 percent of American children have it, and the CDC estimates that 4.4 million children between ages 7 and 14 have been diagnosed [sources: NIMH, CDC]. ADHD is a genetic condition -- not something acquired or caused by life experience or insufficient parental supervision. It develops gradually in early childhood, usually by age 7, and occurs more often in boys than girls.


Contrary to some rumors, ADHD is not a new disorder, nor an amalgamation of disparate symptoms. In 1845, a doctor named Heinrich Hoffman described the then-unnamed disorder in a book titled "The Story of Fidgety Book." In 1902, Sir George Frederick Still, a pediatric physician in Britain who later served the royal family, delivered lectures detailing the condition.

On the next page, we'll look at some causes of ADHD and how the brain of an ADHD patient differs from that of someone without the condition


Causes of ADHD and the ADHD Brain

While sugar cubes might rot your teeth, research has shown that sugar doesn't affect behavior.
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Despite the intense scrutiny it has faced, scientists have yet to produce a single, definitive cause for ADHD. There are some things that researchers are certain don't cause it, such as a child's surroundings and upbringing. (While environmental factors can cause a child further difficulties or make a case of ADHD more pronounced, they don't produce the disorder itself.) Research has knocked certain theories out of contention -- for example, studies examining the effects of refined sugars and other food additives show that they have little to no effect on behavior -- and the remaining candidates all indicate underlying genetic or neurological causes [source: NIMH]. Additionally, there seems to be a strong hereditary component to ADHD, and prenatal exposure to alcohol and cigarettes may make the condition worse.

General consensus among researchers now points to some genes playing major roles in ADHD's development, with numerous, as yet unidentified genes likely playing smaller parts. Following that premise, ADHD doesn't appear to be caused by one basic genetic defect. Instead, it's the result of interactions produced by many genes and systems working together. When some of those genes contain defects, the systems governing behavior are thrown out of whack.


Recent studies have shown actual anatomical and structural differences in the brains of children with ADHD versus those without the condition. These studies indicate that the brain's frontal lobe is involved with the development of ADHD. Weak connections between areas of the frontal lobe may contribute to some of the disorder's symptoms.


Some research involving brain scans shows that children with ADHD had smaller frontal and temporal lobes. The frontal lobe controls, among other things, planning and attention, both of which are negatively affected by ADHD. In one study, two other areas of the brain, the temporal and inferior parietal cortices, showed increased gray matter -- up to 24 percent more [source: Psychiatric News]. More gray matter appeared to contribute to inattention, and the bigger frontal lobe seemed to boost hyperactivity. Although the children studied were or had been on stimulant medications, as commonly prescribed, researchers didn't believe that the changes in brain size were caused by the use of medication [source: Psychiatric News].

Another study found overall brain shrinkage of 3 to 4 percent among children with ADHD [source: NIH]. This study determined that using ADHD medication didn't hurt the brain and might actually aid brain development. Children who hadn't used medication had even less white matter than those with ADHD who had medicated. White matter helps to connect different parts of the brain, and those with more, or thicker, white matter tend to have more developed brains. ­

Despite all these new discoveries about the brain and ADHD, some studies show conflicting or overlapping results. Many avenues of research remain to be explored, with much attention focused on how brain structure and neural connections change in ADHD patients. Now, let's take a look at ADHD symptoms and how a diagnosis is made.


ADHD Symptoms and Diagnosis

Some kids just can't sit still.
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The Diagnostic and Statistical Manual of Mental Disorders, commonly known as DSM-IV, offers a detailed and rather complicated set of criteria for diagnosing ADHD. The DSM lists two different categories of possible symptoms. Category A contains nine symptoms that fall under the title of Inattention. Category B contains nine symptoms of Hyperactivity-Impulsivity. In order to be used for a diagnosis, the symptoms in question must "have been present for at least six months to a point that is disruptive and inappropriate for developmental level" [source: CDC]. Symptoms of inattention include trouble listening to directions and staying organized, as well as seeming distracted and being forgetful. People who are hyperactive or impulsive may speak or yell when they're not supposed to and disrupt others.

There are three types of possible ADHD diagnosis. The differing names reflect the nature of the patient's symptoms. ADHD, Predominantly Inattentive Type means that the subject has demonstrated symptoms from category A for six months. ADHD, Predominantly Hyperactive-Impulsive Type refers to those who show symptoms from category B for six months. Finally, ADHD, Combined Type is for someone who has shown symptoms from both categories for six months.


L­et's take a closer look at the types of ADHD and their accompanying symptoms. A child of the Predominantly Inattentive Type may have trouble completing tasks, paying attention to instructions and focusing in class. He or she may also appear tired or daydream frequently. This variation of ADHD can be more difficult to detect because the symptoms may be less obvious than those of another type. That isn't usually the case with children of the Predominantly Hyperactive-Impulsive Type, who often show constant energy, can't sit still and need to remain active at all times. Impulsive children don't check and consider their actions or statements. They'll seemingly do things without thinking, such as make inappropriate comments. Someone with the Combined Type of ADHD may show any of the aforementioned symptoms.

An ADHD diagnosis is usually made by a pediatrician, neurologist, psychologist, psychiatrist or trained social worker. Teachers, who work closely with many children and are likely experienced at dealing with ADHD, are often useful in helping to spot possible cases. They can help monitor children and discuss potential issues with parents. Many schools also require teachers to fill out evaluation forms, which a professional considering a diagnosis of ADHD may examine.

In addition to consulting with teachers and parents, the person making the diagnosis may look at a child's behavior during situations that demand restraint and discipline. The practitioner will see how the child's disruptive behaviors affect his life and relationships, when they occur, how long the issues have been present, other complicating factors (such as other disorders) and the situation at home. And while various types of brain scans and magnetic imaging have been used in studying ADHD, specialists don't use these techniques in diagnosing the disorder. Once a child is diagnosed, he or she generally receives treatment (something we'll discuss in a later section) and is re-evaluated and monitored through the years.

ADHD can be misdiagnosed because many children display some of the symptoms of the disorder while not having the disorder itself. Similarly, their symptoms may actually be caused by another disorder or some other personal or social problem. The various types of ADHD can also lead someone to misinterpret or overlook symptoms. A brash, unruly, hyperactive child will attract more attention than one who is quiet, distracted and aloof, although both might be equally afflicted with ADHD.

A child's symptoms might appear only in some environments, such as when he or she is at school. In that case, it may not be ADHD at all. The National Institute of Mental Health states that the symptoms must negatively affect the child's life in more than one environment to be considered ADHD.


ADHD Medications and Treatment

There's lots of controversy over these little white pills.
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While several types of health care professionals can diagnose ADHD, only some may be able to adequately treat the patient since some professionals, like social workers, can't prescribe medication. Both counseling and medication are commonly used in treating ADHD. Many psychiatrists specialize in treating the disorder, and some have further expertise in dealing with children or families.

The first task in treating ADHD is confirming the diagnosis, making sure that the behavior isn't caused by some traumatic event or by a different disorder or disease. You also have to make sure it isn't simple misbehavior. Once that's done, a child may begin some combination of therapy and medication. The child's parents sometimes attend counseling with their child or may undergo separate counseling or find support groups. There are many different approaches that fall under the general title of counseling or therapy, including psychotherapy, behavior therapy and instruction in social skills. Therapy can help a child understand his or her condition and the stresses that accompany it, for example, or learn how to control the impulse to be disruptive in class.


Many medications exist for treating ADHD, but Ritalin and Adderall, which has been approved for use in children as young as 3 years old, are among the best-known. Most ADHD drugs are considered stimulants, with Strattera being a major exception. These stimulants are designed to help children with ADHD maintain focus and concentration. In 10 percent of children, stimulants aren't effective [source: NIMH]. Some patients have to try several different medications or adjust dosages in order to find one that works. And of course, these medications have the potential for side effects, such as lack of appetite, anxiety or insomnia. Children who begin taking medication for ADHD often need to continue doing so as teenagers and as adults.

Ritalin remains a controversial drug. Proponents of Ritalin point out that the drug has been used for more than half a century and that a person can't overdose on Ritalin alone. (An overdose is possible if the medication is taken in combination with other drugs or if other health problems are present.) When properly prescribed, children of all ages have benefited from using Ritalin. Ritalin pumps up dopamine levels in the brain, boosting the patient's ability to focus and concentrate.

Still, some debate persists over whether Ritalin is overprescribed. A study published in a 1998 issue of the Journal of the American Medical Association that found no evidence of widespread overprescription of the medication [source: PsychCentral]. But other authorities, among them the Drug Enforcement Administration (DEA), have found worrying trends. A study released in 2007 found that children of divorced parents were two times more likely to be on Ritalin [source: Reuters]. Since 1993, worldwide ADHD prescriptions have increased by 300 percent [source: Reuters]. In August 2008, a prominent Australian doctor estimated that 30 percent of ADHD cases in Australia are misdiagnosed and that even those properly diagnosed often don't need medication [source: The Daily Telegraph].

Like many medications, Ritalin carries a potential for abuse. Because of the drugs' stimulant properties, college students sometimes use Ritalin and Adderall as study aids. Young people have also been known to crush and snort the drugs, mimicking the effects of cocaine.



Adult ADHD and Related Disorders

Teens with ADHD are much more likely to get in car accidents.
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Many children with ADHD have accompanying disorders, some mild and treatable, others more severe. People with ADHD show an increased rate of substance abuse and are more likely to suffer injuries, particularly as a result of hyperactive or inattentive behavior. A small percentage of adult ADHD cases are accompanied by Tourette syndrome. Among children with ADHD, 33 to 50 percent have oppositional defiant disorder [source: NIMH]. More common among boys than girls, the condition is characterized by an argumentative, difficult, unruly attitude.

Conduct disorder is found in 40 percent of children with ADHD. The National Institute of Mental Health calls it a very serious condition, one that produces potentially dangerous behaviors, in which children may fight, lie, steal or perform other risky or illegal acts [source: NIMH].


Children with ADHD often have trouble in school, a situation made even more difficult for the 20 to 30 percent who have an accompanying learning disorder, such as dyslexia or difficulty with self-expression [source: NIMH]. The stress of dealing with these and other ADHD-related problems can spur the development of anxiety and depression, although proper treatment of ADHD can help to stave off these issues. Some ADHD sufferers also experience bipolar disorder. These conditions often have overlapping symptoms, the manic and depressed states representative of bipolar disorder seem similar to ADHD behavior.

ADHD and its related disorders don't simply disappear as a child passes into adolescence. It's during this time that the problems caused by the disorder can pose the greatest difficulties. For example, teenage drivers with ADHD are much more likely to have auto accidents than those who don't have ADHD [source: NIH].

Many people "outgrow" their ADHD as they enter adulthood. But up to 70 percent of people who have ADHD as children also have it as adults [source: NIMH]. As many as 5 million adults in the U.S. may have undiagnosed ADHD [source: ADDitude]. Some of these undiagnosed cases may suspect something is wrong or may attribute other causes to their issues, which can include difficulty concentrating, multiple car accidents, depression or anxiety.

In diagnosing ADHD in adults, specialists look for signs that the symptoms developed early in childhood and aren't manifestations of other problems. Like children, adults with ADHD often turn to a combination of therapy and medication for treatment, though adults take antidepressants more often than children. Some adults are afraid to confront their condition for fear of how treatment might change them. They may also associate their ADHD with creative or artistic impulses. But numerous testimonials exist of people diagnosed in adulthood with ADHD who received treatment and saw immense improvement in their lives, particularly in their ability to remain organized and complete tasks.

For more information about ADHD and related topics, please check out the links on the next page.


Lots More Information

Related Articles

More Great Links

  • "ADD/ADHD Statement of Drug Enforcement Administration." DEA. Dec. 12, 1996.
  • "Attention Deficit Hyperactivity Disorder." National Institute of Mental Health. April 3, 2008.
  • "Attention-Deficit/Hyperactivity Disorder (ADHD)." CDC. Sept. 20, 2005.
  • "Brain Shrinkage in ADHD Not Caused by Medications." National Institutes of Health. Oct. 8, 2002.
  • "Myths About ADD/ADHD." Attention Deficit Disorder Association.
  • "Research suggests how Ritalin works."
  • "Ritalin." The Partnership for a Drug-Free America.
  • "Symptoms of ADHD." CDC. Sept. 20, 2005.
  • "The Neurobiology of ADHD."
  • Anderson, Scott. "Ritalin use doubles after divorce, study finds." Reuters. June 5, 2007. &view=sphere
  • Baruchin, Aliyah. "Attention Deficits That May Linger Well Past Childhood." New York Times.
  • Baruchin, Aliyah. "Nature, Nurture and Attention Deficit." New York Times.
  • Baruchin, Aliyah. "Things To Know About A.D.H.D." New York Times.
  • Connolly, Maureen. "Adult ADD 101: Diagnosis and Treatment." ADDitude.
  • Farrow, S.J. "Sir George Frederick Still (1868-1941)." Oxford Journals.
  • Framingham, Jane. "Frequently Asked Questions About ADHD." March 27, 2006.
  • Fyfe-Yeomans, Janet and Sikora, Kate. "Medical experts expose ADHD misdiagnoses." The Daily Telegaph. August 21, 2008.,22049,24213952-5006009,00.html
  • Rosack, Jim. "Brain Scans Reveal Physiology of ADHD." Psychiatric News. Jan. 2, 2004.