According to the U.S. National Institute of Mental Health, attention deficit hyperactivity disorder (ADHD) is a legitimate psychologic condition.
ADHD is a syndrome generally characterized by the following symptoms:
Some doctors categorize ADHD into three subtypes:
There is some debate over these criteria. Some argue the condition is overdiagnosed. Others say it's underdiagnosed. (See Difficulties in Identifying Children with ADHD section in this report.) One-third of cases are accompanied by learning disabilities and other neurologic or emotional problems, making an ADHD diagnosis particularly difficult. It is likely that the term attention-deficit hyperactivity disorder will eventually give way to subgroups of problems that include some of these general symptoms.
In the United States, about 4.7 million children ages 3 - 17 have been diagnosed at some point with ADHD. This accounts for 7.4% of all American children in this age range.
ADHD is a genuine disorder, but it is telling that the U.S. accounts for 90% of worldwide prescriptions for stimulants for ADHD. It is not known whether this reflects a real increase in ADHD, or a better ability to recognize it. Some say it may be an indication of a culture that places excessive value on normalcy and academic achievement at the expense of more frequent diagnoses.
Symptoms of ADHD usually occur around the age of 7. Studies indicate that ADHD symptoms in preschool children with ADHD do not differ significantly from older children.
The classic ADHD symptoms do not always adequately describe the child's behavior, nor do they describe what is actually happening in the child's mind. Some researchers focused on deficits in "executive functions" of the brain to understand and describe all ADHD behaviors. Such impaired executive functions in ADHD children can cause the following problems:
Hyperactivity. The term hyperactive is often confusing since, for some, it suggests a child racing around non-stop. A boy with ADHD playing a game, for instance, may have the same level of activity as another child without the syndrome. But when a high demand is placed on the child's attention, his brain motor activity intensifies beyond the levels of the other children. In a busy environment, such as a classroom or a crowded store, children with ADHD often become distracted and react by pulling items off the shelves, hitting people, or spinning out of control into erratic, silly, or strange behavior.
Impulsivity and Temper Explosions. Even before the "terrible twos," impulsive behavior is often apparent. The toddler may gleefully make erratic and aggressive gestures, such as hair pulling, pinching, and hitting. Temper tantrums, normal in children after age 2, are usually exaggerated and not necessarily linked to a specific negative event in the life of a child with ADHD. One of the most painful events a parent may experience is an abrupt and aggressive attack that may occur after cuddling a young child with ADHD. Often this reaction seems to be caused not by anger, but by the child's apparent inability to endure overstimulation or displays of physical affection.
Attention and Concentration. Children with ADHD are usually distracted and made inattentive by an overstimulating environment (such as a large classroom). They are also inattentive when a situation is low-key or dull. Some researchers theorize that certain parts of the brain in ADHD children may be underactive, so the children fail to be aroused by nonstimulating activities. In contrast, they may exhibit a kind of "super concentration" to a highly stimulating activity (such as a video game or a highly specific interest). Such children may even become over-attentive -- so absorbed in a project that they cannot modify or change the direction of their attention.
Impaired Short-Term Memory. Many doctors now believe that an essential feature in ADHD, as well as in learning disabilities, is an impaired working (also called short-term) memory. People with ADHD can't hold groups of sentences and images in their mind long enough to extract organized thoughts. They are not necessarily inattentive. Instead, a patient with ADHD may be unable to remember a full explanation (such as a homework assignment), or unable to complete processes that require remembering sequences, such as model building. In general, children with ADHD are often attracted to activities (television, computer games, or active individual sports) that do not tax the working memory, or produce distractions. Children with ADHD have no differences in long-term memory compared with other children.
Inability to Manage Time. Studies suggest that children with ADHD have difficulties being on time and planning the correct amount of time to complete tasks. (This may coincide with short-term memory problems.)
Lack of Adaptability. Children with ADHD have a very difficult time adapting to even minor changes in routines, such as getting up in the morning, putting on shoes, eating new foods, or going to bed. Any shift in a situation can precipitate a strong and noisy negative response. Even when they are in a good mood, they may suddenly shift into a tantrum if met with an unexpected change or frustration. In one experiment, These children can closely focus their attention when directly cued to a specific location, but they have difficulty shifting their attention to an alternative location.
Hypersensitivity and Sleep Problems.. Children with ADHD are often hypersensitive to sights, sounds, and touch. They may complain excessively about stimuli that seem low key or bland to others. Sleeping problems usually occur well after the point when most small children sleep through the night. In one study, 63% of children with ADHD had trouble sleeping.
Although ADHD is primarily thought of as a childhood disorder, diagnoses of attention-deficit disorder in adults are on the rise. Methylphenidate (Ritalin) was prescribed for nearly 800,000 adults in the U.S. in 1997, nearly three times the number in 1992. It is estimated that ADHD affects about 4.1% of adults ages 18 - 44 years in a given year. The disorder appears to be distributed equally between adult women and men.
Accompanying Mental Health Disorders. About 20 % of adults with ADHD also have major depression or bipolar disorder. Up to 50 % have an anxiety disorder. Bipolar disorder plus ADHD, in fact, may be very difficult to differentiate from ADHD alone in adults.
Accompanying Learning Disorders. About 20% of adults with ADHD have learning disorders, usually dyslexia and auditory processing problems. These problems should be considered in any treatment plan.
Effect on Work. Compared to adults without ADHD, those with the condition tend to reach lower educational levels, earn less money, and be fired more often. In fact, one study reported that by the time they are in their 30s, about 35% of ADHD adults are self-employed.
Substance Abuse. About 1 in 5 adults with ADHD also contend with substance abuse. Studies indicate that adolescents with ADHD are twice as likely to smoke cigarettes as their peers who do not have ADHD. Cigarette smoking during adolescence is a risk factor for the development of substance abuse in adulthood.
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