|
As early as the 1940's, psychiatrists have labeled children with
hyperactivity and extremely distracted and impulsive. Such children
have said to have "minimal brain dysfunction," "brain-injured child
syndrome," hyper kinetic reaction of childhood," "hyperactive child
syndrome," and "attention-deficit disorder (ADD)." These frequent label
changes show how uncertain researchers are about the causes of, and the
diagnostic criteria for the disorders.
In the past several years, the people who study ADHD have commenced
to clarify the disorder's symptoms and causes, and have reason to
believe that it may be genetic. Today's view on this disorder is very
different from the beliefs of just a few years ago. Researchers are
finding that ADHD is not a disorder of just attention, but is from a
developmental failure in the brain's circuitry and control for
inhibition and self-control. The loss of self-control weakens other
important brain functions mandatory for maintaining attention.
ADHD involves two sets of symptoms: inattention and a combination of
hyperactive and impulsive behaviors. Most children are more active and
distractive than adults are. Children are more inconsistent, affected
by brief actions and dominated by objects in their environment. The
younger the child, the less aware of time they are. This behavior is a
sign of a problem when it is displayed more in them than in their
peers. Boys are at least three times more prone than girls to develop
ADHD. Studies have found that ADHD in boys outnumber girls 9 to 1, this
is believed to be because boys are genetically likely to develop
disorders in the nervous system. These behaviors generally occur
between the ages of 3 and 5, even though some children don't start to
develop the disorder until late childhood or early adolescence.
Researchers are unable to find the reasons why this delay occurs.
Studies estimated that between 2 and 9. 5 percent of all school-age
children have ADHD; this is true in every culture and nation studied
throughout the word. Researchers had believes that this disorder only
existed in childhood and went away with age. Now they have found that
ADHD can continue into adulthood. Approximately 2/3 of 158 children
studied with ADHD in the 1970's, still had the disorder in there
twenties. Many of these people still have major adjustment problems at
work, school or in other social places. Psychiatrists and psychologist
are trying to better understand the causes of ADHD to help children and
adults with the disorder. Researchers have usually viewed ADHD as a
dysfunction in the realm of attention. Some say that is from a failure
to filter sensory inputs such as sights and sounds.
Joseph A. Sergeant of the University of Amsterdam has shown that
children with ADHD do not have difficulty in this particular area. They
have problems with reducing their spontaneous motor responses to such
input. Other researchers have reason to believe that children with ADHD
are less able to organize motor responses in anticipation to events.
Children with ADHD are also usually too insensitive to criticism about
them and their actions. Children with ADHD are less likely than other
children to do well on a commonly used test of reaction time. Other
children are more capable of pressing one of the several keys when they
see a warning light. These tests allow them to slow down after making
mistakes in order to better their performance, but children with ADHD
do not take this opportunity to better their test scores.
Resource: http://www.sciam.com/1998/0998issue/0998barkely.html
|
(0 vote)