attention deficit hyperactivity disorder
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attention deficit hyperactivity disorder(ADHD), formerly called hyperkinesis or minimal brain dysfunction, a chronic, neurologically based syndrome characterized by any or all of three types of behavior: hyperactivity, distractibility, and impulsivity. Hyperactivity refers to feelings of restlessness, fidgeting, or inappropriate activity (running, wandering) when one is expected to be quiet; distractibility to heightened distraction by irrelevant sights and sounds or carelessness and inability to carry simple tasks to completion; and impulsivity to socially inappropriate speech (e.g., blurting out something without thinking) or striking out. Unlike similar behaviors caused by emotional problems or anxiety, ADHD does not fluctuate with emotional states; sleep deprivation may also cause symptoms in children that resemble those of ADHD. While the three typical behaviors occur in nearly everyone from time to time, in those with ADHD they are excessive, long-term, and pervasive and create difficulties in school, at home, or at work. ADHD is usually diagnosed before age seven. It is often accompanied by a learning disability.
The cause of ADHD is unknown, although there appears to be a genetic component in some cases. Intake of sugars is no longer considered to be a factor. Some studies suggest that although food additives, such as colorings, do not cause symptoms in the general population, they may aggravate hyperactivity in some susceptible individuals. It has been shown that people with ADHD have less activity in areas of the brain that control attention. Treatment usually includes behavioral therapy and emotional counseling combined with medications such as methylphenidate hydrochloride (Ritalin), dextroamphetamine (Dexedrine), or a combination drug called Adderall that correct neurochemical imbalances in the brain; over the long term, however, such medications do not appear to offer any benefits. Although symptoms may decrease after adolescence, they often persist into adulthood.
See A. Schwarz, ADHD Nation (2016).
Attention deficit hyperactivity disorder
A common psychiatric disorder of childhood characterized by attentional difficulties, impulsivity, and hyperactivity; known earlier as attention deficit disorder. Other older names for this disorder include minimal brain dysfunction, minimal brain damage, hyperactivity, hyperkinesis, and hyperactive child syndrome. Over time, these names were modified due to their implications about etiology and core symptoms: minimal brain dysfunction seemed to imply that children with this disorder were brain-damaged, while hyperactivity and its synonyms named a feature seen in many but not all of these children.
The three defining symptoms of attention deficit disorder are as follows:
(1) Attentional deficits. The child is described as having a short attention span. The child often fails to finish things he or she starts, does not seem to listen, and is easily distracted or disorganized. In more severe instances the child is unable to focus attention on anything, while in less severe cases attention can be focused on things of interest to the child.
(2) Impulsivity. The child is often described as acting before thinking, shifting excessively and rapidly from one activity to another, or having difficulty waiting for a turn in games or group activities.
(3) Hyperactivity. Many children with this disorder are hyperactive—and indeed, may have been noted to be so prior to birth. They may fidget, wiggle, move excessively, and have difficulty keeping still. This excessive activity is not noticeable when the children are playing; however, in the classroom or other quiet settings, the child cannot decrease his or her activity appropriately. Some affected children are active at a normal level or even sluggish. On the basis of the predominating symptoms, children with attention deficit hyperactivity disorder are subcategorized as having hyperactive symptoms (hyperactive type), lacking hyperactivity (inattentive type), and having both inattention and hyperactivity or impulsivity (combined type).
Many children with attention deficit hyperactivity disorder frequently show an altered response to socialization. They are often described by their parents as obstinate, impervious, stubborn, or negativistic. With peers, many affected children are domineering or bullying, and thus may prefer to play with younger children. Another characteristic often seen in children with the disorder is emotional lability. Their moods change frequently and easily, sometimes spontaneously, and sometimes reactively. Because of their behavioral difficulties, children with the disorder often have conflicts with parents, teachers, and peers. Commonly, difficulties in discipline and inadequacies in schoolwork lead to reproof and criticism. As a consequence, children with the disorder usually also have low self-esteem. Attention deficit hyperactivity disorder is frequently associated with other disorders, including disruptive behavior disorders, internalizing (mood and anxiety) disorders, and developmental disorders. See Affective disorders
Formerly believed to be largely caused by brain damage, and more recently believed by some to be caused by food allergy, attention deficit hyperactivity disorder is now considered to be mainly hereditary. It is estimated that 3–10% of children of elementary school age (roughly 6–19 years) manifest significant symptoms of attention deficit hyperactivity disorder. About twice as many boys as girls are affected with the disorder. The girls are much less likely than the boys to be aggressive and have serious behavioral difficulties, making the girls vulnerable to underidentification and undertreatment. It was formerly believed that attention deficit hyperactivity disorder was out-grown during adolescence. Although some signs of the disorder such as excessive activity may diminish or disappear in some affected children, other signs such as attentional difficulties, impulsivity, and interpersonal problems may persist. Despite the fact that this disorder is not uncommon in adults, the lower rates of hyperactivity in adults may result in the condition being frequently overlooked.
The treatment of the child or adult with this disorder involves three steps: evaluation, explanation of the problem to parents and child, and therapeutic intervention. Evaluation requires a detailed history of the child's psychological development and current functioning. Next, because the disorder is frequently associated with learning problems in school, it is desirable to obtain an individual intelligence test as well as a test of academic achievement. Since attention deficit hyperactivity disorder is often associated with other psychiatric disorders, it is important to carefully evaluate the presence of these other conditions. If a diagnosis of attention deficit hyperactivity disorder is confirmed, the parents or family should be educated regarding the nature of the condition and other associated conditions. Medication and guidance are the mainstays of the treatment. Approximately 70–80% of the children manifest a therapeutic response to one of the major stimulant drugs, such as amphetamines and methylphenidate. When effective, these medications increase attention, decrease impulsivity, and usually make the child more receptive to parental and educational requests and demands. Hyperactivity, when present, is usually diminished as well. Although usually less effective, other medications can be helpful to individuals who cannot tolerate or do not respond to stimulants. The common mechanism of action for such medications is their impact upon the neurotransmitters dopamine and norepinephrine.