Below are two short articles from the National Institute of Neurological Disorders and Stroke and, also from the staff of the Mayo Clinic as well, plus a more comprehensive presentation from the National Institute of Health. We’ve included these articles for you so you can go progressively deeper into understanding the basic’s of what autism is. We have also included a list of references to serve as a starting point for further search results.
National Institute of Neurological Disorders and Stroke
WHAT IS AUTISM?
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.
By Mayo Clinic June 2, 2006
Mayoclinic.com Bookstore
Autism - Signs and Symptoms
In general, children with autism have problems in three crucial areas of development — social skills,
language and behavior. The most severe autism is marked by a complete inability to communicate or
interact with other people.
Because the symptoms of autism vary widely, two children with the same diagnosis may act quite differently
and have strikingly different skills.
If your child has autism, he or she may develop normally for the first few months — or years — of life and
then later become less responsive to other people, including you. You may recognize the following signs in
the areas of social skills, language and behavior:
Social skills
Fails to respond to his or her name
Has poor eye contact
Appears not to hear you at times
Resists cuddling and holding
Appears unaware of others' feelings
Seems to prefer playing alone — retreats into his or her "own world"
Language
Starts talking later than other children
Loses previously acquired ability to say words or sentences
Does not make eye contact when making requests
Speaks with an abnormal tone or rhythm — may use a singsong voice or robot-like speech
Can't start a conversation or keep one going
May repeat words or phrases verbatim, but doesn't understand how to use them
Behavior
Performs repetitive movements, such as rocking, spinning or hand-flapping
Develops specific routines or rituals
Becomes disturbed at the slightest change in routines or rituals
Moves constantly
May be fascinated by parts of an object, such as the spinning wheels of a toy car
May be unusually sensitive to light, sound and touch
Young children with autism also have a hard time sharing experiences with others. When someone reads to
them, for example, they're unlikely to point at pictures in the book. This early-developing social skill is crucial
to later language and social development.
As they mature, some children with autism become more engaged with others and show less marked
disturbances in behavior. Some, usually those with the least severe impairments, eventually may lead
normal or near-normal lives. Others, however, continue to have severe impairments in language or social
skills, and the adolescent years can mean a worsening of behavior problems.
The majority of children with autism are slow to acquire new knowledge or skills. However, some children
with autism have normal to high intelligence. These children learn quickly yet have trouble communicating,
applying what they know in everyday life and adjusting in social situations. An extremely small number of
children with autism are "autistic savants" and have exceptional skills in a specific area, such as art or math.
Autism Discussion on what Autism is
Introduction
Not until the middle of the twentieth century was there a name for a disorder that now appears to affect an
estimated 3.4 every 1,000 children ages 3-10, a disorder that causes disruption in families and unfulfilled
lives for many children. In 1943 Dr. Leo Kanner of the Johns Hopkins Hospital studied a group of 11 children
and introduced the label early infantile autism into the English language. At the same time a German
scientist, Dr. Hans Asperger, described a milder form of the disorder that became known as Asperger
syndrome. Thus these two disorders were described and are today listed in the Diagnostic and Statistical
Manual of Mental Disorders DSM-IV-TR (fourth edition, text revision)1 as two of the five pervasive
developmental disorders (PDD), more often referred to today as autism spectrum disorders (ASD). All these
disorders are characterized by varying degrees of impairment in communication skills, social interactions,
and restricted, repetitive and stereotyped patterns of behavior.
The autism spectrum disorders can often be reliably detected by the age of 3 years, and in some cases as
early as 18 months.2 Studies suggest that many children eventually may be accurately identified by the age
of 1 year or even younger. The appearance of any of the warning signs of ASD is reason to have a child
evaluated by a professional specializing in these disorders.
Parents are usually the first to notice unusual behaviors in their child. In some cases, the baby seemed
“different” from birth, unresponsive to people or focusing intently on one item for long periods of time. The
first signs of an ASD can also appear in children who seem to have been developing normally. When an
engaging, babbling toddler suddenly becomes silent, withdrawn, self-abusive, or indifferent to social
overtures, something is wrong. Research has shown that parents are usually correct about noticing
developmental problems, although they may not realize the specific nature or degree of the problem.
The pervasive developmental disorders, or autism spectrum disorders, range from a severe form, called
autistic disorder, to a milder form, Asperger syndrome. If a child has symptoms of either of these disorders,
but does not meet the specific criteria for either, the diagnosis is called pervasive developmental disorder
not otherwise specified (PDD-NOS). Other rare, very severe disorders that are included in the autism
spectrum disorders are Rett syndrome and childhood disintegrative disorder. This brochure will focus on
classic autism, PDD-NOS, and Asperger syndrome, with brief descriptions of Rett syndrome and childhood
disintegrative disorder on the following page.
Rare Autism Spectrum Disorders
Rett Syndrome
Rett syndrome is relatively rare, affecting almost exclusively females, one out of 10,000 to 15,000. After a
period of normal development, sometime between 6 and 18 months, autism-like symptoms begin to appear.
The little girl's mental and social development regresses—she no longer responds to her parents and pulls
away from any social contact. If she has been talking, she stops; she cannot control her feet; she wrings her
hands. Some of the problems associated with Rett syndrome can be treated. Physical, occupational, and
speech therapy can help with problems of coordination, movement, and speech.
Scientists sponsored by the National Institute of Child Health and Human Development have discovered that
a mutation in the sequence of a single gene can cause Rett syndrome. This discovery may help doctors
slow or stop the progress of the syndrome. It may also lead to methods of screening for Rett syndrome, thus
enabling doctors to start treating these children much sooner, and improving the quality of life these
children experience.*
Childhood Disintegrative Disorder
Seizures and a very low IQ
*Rett syndrome. NIH Publication No. 01-4960. Rockville, MD: National Institute of Child Health and Human
Development, 2001. Available at http://www.nichd.nih.gov/publications/pubskey.cfm?from=autism
**Frombonne E. Prevalence of childhood disintegrative disorder. Autism, 2002; 6(2): 149-157.
***Volkmar RM and Rutter M. Childhood disintegrative disorder: Results of the DSM-IV autism field trial.
Journal of the American Academy of Child and Adolescent Psychiatry, 1995; 34: 1092-1095.
What Are the Autism Spectrum Disorders?
The autism spectrum disorders are more common in the pediatric population than are some better known
disorders such as diabetes, spinal bifida, or Down syndrome.2 Prevalence studies have been done in
several states and also in the United Kingdom, Europe, and Asia. A recent study of a U.S. metropolitan area
estimated that 3.4 of every 1,000 children 3-10 years old had autism.3 This wide range of prevalence points
to a need for earlier and more accurate screening for the symptoms of ASD. The earlier the disorder is
diagnosed, the sooner the child can be helped through treatment interventions. Pediatricians, family
physicians, daycare providers, teachers, and parents may initially dismiss signs of ASD, optimistically
thinking the child is just a little slow and will “catch up.” Although early intervention has a dramatic impact on
reducing symptoms and increasing a child's ability to grow and learn new skills, it is estimated that only 50
percent of children are diagnosed before kindergarten.
All children with ASD demonstrate deficits in 1) social interaction, 2) verbal and nonverbal communication,
and 3) repetitive behaviors or interests. In addition, they will often have unusual responses to sensory
experiences, such as certain sounds or the way objects look. Each of these symptoms runs the gamut from
mild to severe. They will present in each individual child differently. For instance, a child may have little
trouble learning to read but exhibit extremely poor social interaction. Each child will display communication,
social, and behavioral patterns that are individual but fit into the overall diagnosis of ASD.
Children with ASD do not follow the typical patterns of child development. In some children, hints of future
problems may be apparent from birth. In most cases, the problems in communication and social skills
become more noticeable as the child lags further behind other children the same age. Some other children
start off well enough. Oftentimes between 12 and 36 months old, the differences in the way they react to
people and other unusual behaviors become apparent. Some parents report the change as being sudden,
and that their children start to reject people, act strangely, and lose language and social skills they had
previously acquired. In other cases, there is a plateau, or leveling, of progress so that the difference
between the child with autism and other children the same age becomes more noticeable.
ASD is defined by a certain set of behaviors that can range from the very mild to the severe. The following
possible indicators of ASD were identified on the Public Health Training Network Webcast, "Autism Among
Us.4"
Possible Indicators of Autism Spectrum Disorders
• Does not babble, point, or make meaningful gestures by 1 year of age
• Does not speak one word by 16 months
• Does not combine two words by 2 years
• Does not respond to name
• Loses language or social skills
Some Other Indicators
• Poor eye contact
• Doesn't seem to know how to play with toys
• Excessively lines up toys or other objects
• Is attached to one particular toy or object
• Doesn't smile
• At times seems to be hearing impaired
Social Symptoms
From the start, typically developing infants are social beings. Early in life, they gaze at people, turn toward voices, grasp a finger, and even smile. In contrast, most children with ASD seem to have tremendous
difficulty learning to engage in the give-and-take of everyday human interaction. Even in the first few months
of life, many do not interact and they avoid eye contact. They seem indifferent to other people, and often
seem to prefer being alone. They may resist attention or passively accept hugs and cuddling. Later, they
seldom seek comfort or respond to parents' displays of anger or affection in a typical way. Research has
suggested that although children with ASD are attached to their parents, their expression of this attachment
is unusual and difficult to “read.” To parents, it may seem as if their child is not attached at all. Parents who
looked forward to the joys of cuddling, teaching, and playing with their child may feel crushed by this lack of
the expected and typical attachment behavior.
Children with ASD also are slower in learning to interpret what others are thinking and feeling. Subtle social
cues—whether a smile, a wink, or a grimace—may have little meaning. To a child who misses these cues,
“Come here” always means the same thing, whether the speaker is smiling and extending her arms for a
hug or frowning and planting her fists on her hips. Without the ability to interpret gestures and facial
expressions, the social world may seem bewildering. To compound the problem, people with ASD have
difficulty seeing things from another person's perspective. Most 5-year-olds understand that other people
have different information, feelings, and goals than they have. A person with ASD may lack such
understanding. This inability leaves them unable to predict or understand other people's actions.
Although not universal, it is common for people with ASD also to have difficulty regulating their emotions.
This can take the form of “immature” behavior such as crying in class or verbal outbursts that seem
inappropriate to those around them. The individual with ASD might also be disruptive and physically
aggressive at times, making social relationships still more difficult. They have a tendency to “lose control,”
particularly when they're in a strange or overwhelming environment, or when angry and frustrated. They
may at times break things, attack others, or hurt themselves. In their frustration, some bang their heads, pull
their hair, or bite their arms.
Communication Difficulties
By age 3, most children have passed predictable milestones on the path to learning language; one of the
earliest is babbling. By the first birthday, a typical toddler says words, turns when he hears his name, points
when he wants a toy, and when offered something distasteful, makes it clear that the answer is “no.”
Some children diagnosed with ASD remain mute throughout their lives. Some infants who later show signs of
ASD coo and babble during the first few months of life, but they soon stop. Others may be delayed,
developing language as late as age 5 to 9. Some children may learn to use communication systems such as
pictures or sign language.
Those who do speak often use language in unusual ways. They seem unable to combine words into
meaningful sentences. Some speak only single words, while others repeat the same phrase over and over.
Some ASD children parrot what they hear, a condition called echolalia. Although many children with no ASD
go through a stage where they repeat what they hear, it normally passes by the time they are 3.
Some children only mildly affected may exhibit slight delays in language, or even seem to have precocious
language and unusually large vocabularies, but have great difficulty in sustaining a conversation. The “give
and take” of normal conversation is hard for them, although they often carry on a monologue on a favorite
subject, giving no one else an opportunity to comment. Another difficulty is often the inability to understand
body language, tone of voice, or “phrases of speech.” They might interpret a sarcastic expression such as
“Oh, that's just great” as meaning it really IS great.
While it can be hard to understand what ASD children are saying, their body language is also difficult to
understand. Facial expressions, movements, and gestures rarely match what they are saying. Also, their
tone of voice fails to reflect their feelings. A high-pitched, sing-song, or flat, robot-like voice is common.
Some children with relatively good language skills speak like little adults, failing to pick up on the “kid-
speak” that is common in their peers.
Without meaningful gestures or the language to ask for things, people with ASD are at a loss to let others
know what they need. As a result, they may simply scream or grab what they want. Until they are taught
better ways to express their needs, ASD children do whatever they can to get through to others. As people
with ASD grow up, they can become increasingly aware of their difficulties in understanding others and in
being understood. As a result they may become anxious or depressed.
Repetitive Behaviors
Although children with ASD usually appear physically normal and have good muscle control, odd repetitive
motions may set them off from other children. These behaviors might be extreme and highly apparent or
more subtle. Some children and older individuals spend a lot of time repeatedly flapping their arms or
walking on their toes. Some suddenly freeze in position.
As children, they might spend hours lining up their cars and trains in a certain way, rather than using them
for pretend play. If someone accidentally moves one of the toys, the child may be tremendously upset. ASD
children need, and demand, absolute consistency in their environment. A slight change in any routine—in
mealtimes, dressing, taking a bath, going to school at a certain time and by the same route—can be
extremely disturbing. Perhaps order and sameness lend some stability in a world of confusion.
Repetitive behavior sometimes takes the form of a persistent, intense preoccupation. For example, the
child might be obsessed with learning all about vacuum cleaners, train schedules, or lighthouses. Often
there is great interest in numbers, symbols, or science topics.
Problems That May Accompany ASD
Sensory problems
When children's perceptions are accurate, they can learn from what they see, feel, or hear. On the other
hand, if sensory information is faulty, the child's experiences of the world can be confusing. Many ASD
children are highly attuned or even painfully sensitive to certain sounds, textures, tastes, and smells. Some
children find the feel of clothes touching their skin almost unbearable. Some sounds—a vacuum cleaner, a
ringing telephone, a sudden storm, even the sound of waves lapping the shoreline—will cause these
children to cover their ears and scream.
In ASD, the brain seems unable to balance the senses appropriately. Some ASD children are oblivious to
extreme cold or pain. An ASD child may fall and break an arm, yet never cry. Another may bash his head
against a wall and not wince, but a light touch may make the child scream with alarm.
Mental retardation
Many children with ASD have some degree of mental impairment. When tested, some areas of ability may
be normal, while others may be especially weak. For example, a child with ASD may do well on the parts of
the test that measure visual skills but earn low scores on the language subtests.
Seizures
One in four children with ASD develops seizures, often starting either in early childhood or adolescence. 5
Seizures, caused by abnormal electrical activity in the brain, can produce a temporary loss of
consciousness (a “blackout”), a body convulsion, unusual movements, or staring spells. Sometimes a
contributing factor is a lack of sleep or a high fever. An EEG (electroencephalogram—recording of the
electric currents developed in the brain by means of electrodes applied to the scalp) can help confirm the
seizure's presence.
In most cases, seizures can be controlled by a number of medicines called “anticonvulsants.” The dosage
of the medication is adjusted carefully so that the least possible amount of medication will be used to be
effective.
Fragile X syndrome
This disorder is the most common inherited form of mental retardation. It was so named because one part
of the X chromosome has a defective piece that appears pinched and fragile when under a microscope.
Fragile X syndrome affects about two to five percent of people with ASD. It is important to have a child with
ASD checked for Fragile X, especially if the parents are considering having another child. For an unknown
reason, if a child with ASD also has Fragile X, there is a one-in-two chance that boys born to the same
parents will have the syndrome. 6 Other members of the family who may be contemplating having a child
may also wish to be checked for the syndrome.
Tuberous Sclerosis.
Tuberous sclerosis is a rare genetic disorder that causes benign tumors to grow in the brain as well as in
other vital organs. It has a consistently strong association with ASD. One to 4 percent of people with ASD
also have tuberous sclerosis.
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National Institute of Neurological Disorders and Stroke, Mayo Clinic, National Institute of Health, classical autism, autism spectrum, disorders, ASDs, Asperger syndrome, Rett syndrome