 |
Additional Information
|
|
What is autism?
Autism (sometimes called “classical autism”)
is the most common condition in a group of developmental
disorders known as the autism spectrum disorders (ASDs). Autism
is characterized by impaired social interaction, problems
with verbal and nonverbal communication, and unusual, repetitive,
or severely limited activities and interests. Other
ASDs include Asperger syndrome, Rett syndrome, childhood
disintegrative disorder, and pervasive developmental disorder
not otherwise specified (usually referred to as PDD-NOS). Experts
estimate that three to six children out of every 1,000 will
have autism. Males are four times more likely to
have autism than females.
What are some common signs of autism?
There are three distinctive behaviors that characterize
autism. Autistic children have difficulties
with social interaction, problems with verbal and nonverbal
communication, and repetitive behaviors or narrow, obsessive
interests. These behaviors can range in impact from
mild to disabling.
The hallmark feature of autism is impaired social interaction. Parents
are usually the first to notice symptoms of autism in their
child. As early as infancy, a baby with autism may
be unresponsive to people or focus intently on one item to
the exclusion of others for long periods of time. A
child with autism may appear to develop normally and then
withdraw and become indifferent to social engagement.
Children with autism may fail to respond to their name and
often avoid eye contact with other people. They have
difficulty interpreting what others are thinking or feeling
because they can’t understand social cues, such as
tone of voice or facial expressions, and don’t watch
other people’s faces for clues about appropriate behavior. They
lack empathy.
Many children with autism engage in repetitive movements
such as rocking and twirling, or in self-abusive behavior
such as biting or head-banging. They also tend to start
speaking later than other children and may refer to themselves
by name instead of “I” or “me.” Children
with autism don’t know how to play interactively with
other children. Some speak in a sing-song voice about
a narrow range of favorite topics, with little regard for
the interests of the person to whom they are speaking.
Many children with autism have a reduced sensitivity to
pain, but are abnormally sensitive to sound, touch, or other
sensory stimulation. These unusual reactions may
contribute to behavioral symptoms such as a resistance to
being cuddled or hugged.
Children with autism appear to have a higher than normal
risk for certain co-existing conditions, including fragile
X syndrome (which causes mental retardation), tuberous sclerosis
(in which tumors grow on the brain), epileptic seizures,
Tourette syndrome, learning disabilities, and attention deficit
disorder. For reasons that are still unclear, about
20 to 30 percent of children with autism develop epilepsy
by the time they reach adulthood. While people with
schizophrenia may show some autistic-like behavior, their
symptoms usually do not appear until the late teens or early
adulthood. Most people with schizophrenia also have
hallucinations and delusions, which are not found in autism.
How is autism diagnosed?
Autism varies widely in its severity and symptoms and may
go unrecognized, especially in mildly affected children or
when it is masked by more debilitating handicaps. Doctors
rely on a core group of behaviors to alert them to the possibility
of a diagnosis of autism. These behaviors are:
-
impaired ability to make friends with peers
-
impaired ability to initiate or sustain a conversation
with others
-
absence or impairment of imaginative and social play
-
stereotyped, repetitive, or unusual use of language
-
restricted patterns of interest that are abnormal
in intensity or focus
-
preoccupation with certain objects or subjects
-
inflexible adherence to specific routines or rituals
Doctors will often use a questionnaire or other screening
instrument to gather information about a child’s
development and behavior. Some screening instruments
rely solely on parent observations; others rely on a combination
of parent and doctor observations. If screening instruments
indicate the possibility of autism, doctors will ask for
a more comprehensive evaluation.
Autism is a complex disorder. A comprehensive evaluation
requires a multidisciplinary team including a psychologist,
neurologist, psychiatrist, speech therapist, and other professionals
who diagnose children with ASDs. The team members will
conduct a thorough neurological assessment and in-depth cognitive
and language testing. Because hearing problems can
cause behaviors that could be mistaken for autism, children
with delayed speech development should also have their hearing
tested. After a thorough evaluation, the team usually meets
with parents to explain the results of the evaluation and
present the diagnosis.
Children with some symptoms of autism, but not enough to
be diagnosed with classical autism, are often diagnosed with
PDD-NOS. Children with autistic behaviors but well-developed
language skills are often diagnosed with Asperger syndrome. Children
who develop normally and then suddenly deteriorate between
the ages of 3 to 10 years and show marked autistic behaviors
may be diagnosed with childhood disintegrative disorder. Girls
with autistic symptoms may be suffering from Rett syndrome,
a sex-linked genetic disorder characterized by social withdrawal,
regressed language skills, and hand wringing.
What causes autism?
Scientists aren’t certain what causes autism, but
it’s likely that both genetics and environment play
a role. Researchers have identified
a number of genes associated with the disorder. Studies
of people with autism have found irregularities in several
regions of the brain. Other studies suggest that people
with autism have abnormal levels of serotonin or other neurotransmitters
in the brain. These abnormalities suggest that autism
could result from the disruption of normal brain development
early in fetal development caused by defects in genes that
control brain growth and that regulate how neurons communicate
with each other. While these findings are intriguing,
they are preliminary and require further study. The
theory that parental practices are responsible for autism
has now been disproved.
What role does inheritance
play?
Recent studies strongly suggest that some people have a
genetic predisposition to autism. In families with
one autistic child, the risk of having a second child with
the disorder is approximately 5 percent, or one in 20. This
is greater than the risk for the general population. Researchers
are looking for clues about which genes contribute to this
increased susceptibility. In some cases, parents and
other relatives of an autistic child show mild impairments
in social and communicative skills or engage in repetitive
behaviors. Evidence also suggests that some emotional
disorders, such as manic depression, occur more frequently
than average in the families of people with autism.
Do symptoms of autism change
over time?
For many children, autism symptoms improve with treatment
and with age. Some children with autism grow up to
lead normal or near-normal lives. Children whose language
skills regress early in life, usually before the age of 3,
appear to be at risk of developing epilepsy or seizure-like
brain activity. During adolescence, some children with
autism may become depressed or experience behavioral problems. Parents
of these children should be ready to adjust treatment for
their child as needed.
How is autism treated?
There is no cure for autism. Therapies and behavioral
interventions are designed to remedy specific symptoms and
can bring about substantial improvement. The ideal
treatment plan coordinates therapies and interventions that
target the core symptoms of autism: impaired social
interaction, problems with verbal and nonverbal communication,
and obsessive or repetitive routines and interests. Most
professionals agree that the earlier the intervention, the
better.
-
Educational/behavioral interventions: Therapists
use highly structured and intensive skill-oriented training
sessions to help children develop social and language
skills. Family counseling for the parents and siblings
of children with autism often helps families cope with
the particular challenges of living with an autistic
child.
-
Medications: Doctors often
prescribe an antidepressant medication to handle symptoms
of anxiety, depression, or obsessive-compulsive disorder. Anti-psychotic
medications are used to treat severe behavioral problems. Seizures
can be treated with one or more of the anticonvulsant
drugs. Stimulant drugs, such as those used for
children with attention deficit disorder (ADD), are sometimes
used effectively to help decrease impulsivity and hyperactivity.
-
Other therapies: There are
a number of controversial therapies or interventions
available for autistic children, but few, if any, are
supported by scientific studies. Parents should use caution
before adopting any of these treatments.
To read the rest of this article from the National Institute
of Neurological Disorders and Stroke, please click here: http://www.ninds.nih.gov/disorders/autism/detail_autism.htm |