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What is ADD
Learn More About Attention Deficit Disorder

By , About.com Guide

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What is ADD / ADHD?

The Basics

Attention deficit hyperactivity disorder -- also referred to ADD or ADHD -- is a biological, brain based condition that is characterized by poor attention and distractibility and/or hyperactive and impulsive behaviors. It is one of the most common mental disorders that develop in children. Symptoms may continue into adolescence and adulthood. If left untreated, ADHD can lead to poor school/work performance, poor social relationships and a general feeling of low self esteem. Read more about the basics of ADHD.

Symptoms

The most prevalent symptoms of ADHD are inattention and distractibility and/or hyperactive and impulsive behaviors. Difficulties with concentration, mental focus, and inhibition of impulses and behaviors are chronic and pervasive and impair an individual’s daily functioning across various settings -- home, school or work, in relationships, etc. Read more about the symptoms and diagnostic criteria for ADHD.

Prevalence

It is estimated that between 3 and 5 percent of preschool and school age children have ADHD or approximately two million children in the United States. This means in a class of 25 to 30 students, it is likely that at least one student will have this common condition. ADHD begins in childhood, but it often lasts into adulthood. Studies estimate that 30-70 percent of children with ADHD will continue to have symptoms into adolescence and adulthood. Read more about the prevalence of ADHD.

Causes

The exact cause of ADHD has not been determined, however the condition is thought to have a genetic and biological component. ADHD tends to occur among family members. Many research studies currently focus on identifying which genes, or combination of genes, may cause a person to be more susceptible to ADHD. Physical differences in parts of the brain are also thought to be linked to ADHD. Read more about the causes of ADHD. Watch a video describing the causes.

Risk Factors

Genetics and heredity are the major risk factors, as ADHD tends runs in families. Brain abnormalities or structural differences have also been found in individuals with ADHD. Early brain injury/trauma or other impediment to normal brain development such as exposure to chronic low levels of lead, prematurity, obstetrical complications, cigarette smoke exposure in utero, and malnourishment can all result in a child being at greater risk for ADHD. Read more about the risk factors for ADHD.

ADD versus ADHD - Understanding the Differences

Wondering about the differences between ADD and ADHD? ADD or attention deficit disorder is a general term frequently used to describe individuals that have attention deficit hyperactivity disorder without the hyperactive and impulsive behaviors. The terms are often used interchangeably for both those who do and those who do not have symptoms of hyperactivity and impulsiveness. Read more about the different types of ADHD.

Related Reading:
ADHD: More Than Just Hyperactivity
ADHD is Real
Myths of ADHD
Growing Up with ADHD

Sources:

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition, Text Revision) DSM-IV Washington, D.C. 2000.

Barkley PhD, Russell A. Attention Deficit Hyperactivity Disorders: A Handbook for Diagnosis and Treatment. New York: Guildford Press. 1998.

Center for Disease Control and Prevention. “Prevalence of Diagnosis and Medication Treatment for Attention-Deficit Hyperactivity Disorder: United States, 2003.” Morbidity and Mortality Weekly Report, Mental Health in the United States. 54(34);842-847. 02 Sept. 2005.

National Institute of Mental Health. Department of Health and Human Services. National Institutes of Health. 2006.

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