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What is Autism?

Autism, or autism spectrum disorder (ASD), refers to a broad range of conditions characterized by challenges with social skills, repetitive behaviors, speech and nonverbal communication. Autism spectrum disorder (ASD) is a developmental disorder that affects communication and behavior. Although autism can be diagnosed at any age, it is said to be a “developmental disorder” because symptoms generally appear in the first two years of life.

People with ASD have:

   ♦  Difficulty with communication and interaction with other people

   ♦  Restricted interests and repetitive behaviors

   ♦  Symptoms that hurt the person’s ability to function properly in school, work, and other areas of life

Autism is known as a “spectrum” disorder because there is wide variation in the type and severity of symptoms people experience. ASD occurs in all ethnic, racial, and economic groups. Although ASD can be a lifelong disorder, treatments and services can improve a person’s symptoms and ability to function. A combination of genetic and environmental factors influence the development of autism, and autism often is accompanied by medical issues such as:

   ♦  Gastrointestinal (GI) disorders

   ♦  Seizures

   ♦  Sleep disturbances

Autism affects an estimated 1 in 59 children.

Many people with autism also have sensory issues. These can include aversions to certain sights, sounds and other sensations.

Autism’s hallmark signs usually appear by age 2 to 3. Often, it can be diagnosed as early as 18 months. Some associated development delays can appear even earlier.


Diagnosis in older children and adolescents

ASD symptoms in older children and adolescents who attend school are often first recognized by parents and teachers and then evaluated by the school’s special education team. The school’s team may perform an initial evaluation and then recommend these children visit their primary health care doctor or doctors who specialize in ASD for additional testing.

Parents may talk with these specialists about their child’s social difficulties including problems with subtle communication. These subtle communication issues may include problems understanding tone of voice, facial expressions, or body language. Older children and adolescents may have trouble understanding figures of speech, humor, or sarcasm. Parents may also find that their child has trouble forming friendships with peers.

Diagnosis in adults

Diagnosing ASD in adults is often more difficult than diagnosing ASD in children. In adults, some ASD symptoms can overlap with symptoms of other mental-health disorders, such as anxiety or attention-deficit/hyperactivity disorder (ADHD).

Adults who notice the signs and symptoms of ASD should talk with a doctor and ask for a referral for an ASD evaluation. While testing for ASD in adults is still being refined, adults can be referred to a neuropsychologist, psychologist, or psychiatrist who has experience with ASD. The expert will ask about concerns, such as:

   ♦  Social interaction and communication challenges

   ♦  Sensory issues

   ♦  Repetitive behaviors

   ♦  Restricted interests

Information about the adult’s developmental history will help in making an accurate diagnosis, so an ASD evaluation may include talking with parents or other family members.

Getting a correct diagnosis of ASD as an adult can help a person understand past difficulties, identify his or her strengths, and obtain the right kind of help. Studies are now underway to determine the types of services and supports that are most helpful for improving the functioning and community integration of transition-age youth and adults with ASD.

Mild Autism

The term "mild autism" is not an official diagnosis. It's simply a more descriptive term than "Asperger syndrome" or "autism." Generally speaking, when people use the term mild autism they are referring to individuals whose symptoms fit an autism spectrum diagnosis, but who has strong verbal skills and few behavioral issues. Those individuals may, however, have significant problems with social communication. They may also have problems coping with too much sensory input (loud noise, bright lights, etc.)

Key Points:

   ♦  Mild autism is essentially similar to or identical to Asperger syndrome

   ♦  People with mild autism may be difficult to recognize until they are under stress or coping with complex social situations

   ♦  Most people with mild autism are now considered to have Level 1 Autism Spectrum Disorder

Severe autism

Severe autism is not an official diagnosis; instead, it is a descriptive term along with profound autism, low functioning autism, and classic autism. People with "severe autism" are often non-verbal and intellectually disabled, and may have very challenging behaviors.

Key Points:

   ♦  Severe autism is usually diagnosed as Level 3 Autism Spectrum Disorder

   ♦  Severe autism is extremely challenging and may include aggression and other difficult behaviors

   ♦  Most people with severe autism never gain meaningful use of spoken language

   ♦  Some people with symptoms of severe autism do gain the ability to communicate through signs, picture boards, or other means


Research suggests that autism develops from a combination of genetic and non-genetic, or environmental, influences.

These influences appear to increase the risk that a child will develop autism. However, it’s important to keep in mind that increased risk is not the same as cause. For example, some gene changes associated with autism can also be found in people who don’t have the disorder. Similarly, not everyone exposed to an environmental risk factor for autism will develop the disorder. In fact, most will not.


Genetic factors may be the most significant cause for autism spectrum disorders. Early studies of twins had estimated heritability to be over 90%, meaning that genetics explains over 90% of whether a child will develop autism. However, this may be an overestimation, as new twin studies estimate the heritability at between 60–90%.Many of the non-autistic co-twins had learning or social disabilities. For adult siblings the risk for having one or more features of the broader autism phenotype might be as high as 30%.

However, in spite of the strong heritability, most cases of ASD occur sporadically with no recent evidence of family history. It has been hypothesized that spontaneous de novo mutations in the father's sperm or mother's egg contribute to the likelihood of developing autism. There are two lines of evidence that support this hypothesis.

First, individuals with autism have significantly reduced fecundity, they are 20 times less likely to have children than average, thus curtailing the persistence of mutations in ASD genes over multiple generations in a family. Second, the likelihood of having a child develop autism increases with advancing paternal age,and mutations in sperm gradually accumulate throughout a man's life.


Epigenetic mechanisms may increase the risk of autism. Epigenetic changes occur as a result not of DNA sequence changes but of chromosomal histone modification or modification of the DNA bases. Such modifications are known to be affected by environmental factors, including nutrition, drugs, and mental stress.

Prenatal environment

The risk of autism is associated with several prenatal risk factors, including advanced age in parent, diabetes, bleeding, and use of psychiatric drugs in the mother during pregnancy. Autism has been linked to birth defect agents acting during the first eight weeks from conception, though these cases are rare.

Infectious processes

Prenatal viral infection has been called the principal non-genetic cause of autism. Prenatal exposure to rubella or cytomegalovirus activates the mother's immune response and may greatly increase the risk for autism in mice. Congenital rubella syndrome is the most convincing environmental cause of autism. Infection-associated immunological events in early pregnancy may affect neural development more than infections in late pregnancy, not only for autism, but also for psychiatric disorders of presumed neurodevelopmental origin, notably schizophrenia.

Environmental agents

Teratogens are environmental agents that cause birth defects. Some agents that are theorized to cause birth defects have also been suggested as potential autism risk factors, although there is little to no scientific evidence to back such claims. These include exposure of the embryo to valproic acid, paracetamol, thalidomide or misoprostol. These cases are rare. Questions have also been raised whether ethanol (grain alcohol) increases autism risk, as part of fetal alcohol syndrome or alcohol-related birth defects. All known teratogens appear to act during the first eight weeks from conception, and though this does not exclude the possibility that autism can be initiated or affected later, it is strong evidence that autism arises very early in development.

Other maternal conditions

Thyroid problems that lead to thyroxine deficiency in the mother in weeks 8–12 of pregnancy have been postulated to produce changes in the fetal brain leading to autism.

Thyroxine deficiencies can be caused by inadequate iodine in the diet, and by environmental agents that interfere with iodine uptake or act against thyroid hormones.

Diabetes in the mother during pregnancy is a significant risk factor for autism; a 2009 meta-analysis found that gestational diabetes was associated with a twofold increased risk.

A 2014 review also found that maternal diabetes was significantly associated with an increased risk of ASD. Although diabetes causes metabolic and hormonal abnormalities and oxidative stress, no biological mechanism is known for the association between gestational diabetes and autism risk.

Maternal obesity during pregnancy may also increase the risk of autism, although further study is needed.

Autism’s genetic risk factors

Research tells us that autism tends to run in families. Changes in certain genes increase the risk that a child will develop autism. If a parent carries one or more of these gene changes, they may get passed to a child (even if the parent does not have autism). Other times, these genetic changes arise spontaneously in an early embryo or the sperm and/or egg that combine to create the embryo. Again, the majority of these gene changes do not cause autism by themselves. They simply increase risk for the disorder:

Autism’s environmental risk factors

Research also shows that certain environmental influences may further increase – or reduce – autism risk in people who are genetically predisposed to the disorder. Importantly, the increase or decrease in risk appears to be small for any one of these risk factors:

Increased risk

   ♦  Advanced parent age (either parent)

Pregnancy and birth complications (e.g. extreme prematurity [before 26 weeks], low birth weight, multiple pregnancies [twin, triplet, etc.) Pregnancies spaced less than one year apart

Decreased risk

   ♦  Prenatal vitamins containing folic acid, before and at conception and through pregnancy

No effect on risk

   ♦  Vaccines. Each family has a unique experience with an autism diagnosis, and for some it corresponds with the timing of their child’s vaccinations. At the same time, scientists have conducted extensive research over the last two decades to determine whether there is any link between childhood vaccinations and autism. The results of this research are clear: Vaccines do not cause autism. The American Academy of Pediatrics has compiled a comprehensive list of this research.

Recently several factors have been linked to an increased risk of autism spectrum disorder (ASD):

   ♦  Older parents

   ♦  Poor growth of the fetus in the womb

   ♦  Lack of oxygen when a baby is born

   ♦  Exposure to air pollution during pregnancy.


Early sign of autism

   ♦  Problems with eye contact.

   ♦  No response to his or her name.

   ♦  Problems following another person's gaze or pointed finger to an object (or "joint attention")

   ♦  Poor skills in pretend play and imitation.

   ♦  Problems with nonverbal communication.

Autism’s core symptoms are:

   ♦  Social communication challenges and restricted, repetitive behaviors.

   ♦  In autism, these symptoms begin in early childhood (though they may go unrecognized) persist and interfere with daily living.

Children and adults with autism have difficulty with verbal and non-verbal communication. For example, they may not understand or appropriately use:

   ♦  Spoken language (around a third of people with autism are nonverbal)

   ♦  Gestures

   ♦  Eye contact

   ♦  Facial expressions

   ♦  Tone of voice

   ♦  Expressions not meant to be taken literally

Restricted and repetitive behaviors vary greatly across the autism spectrum.

They can include:

   ♦  Repetitive body movements (e.g. rocking, flapping, spinning, running back and forth)

   ♦  Repetitive motions with objects (e.g. spinning wheels, shaking sticks, flipping levers)

   ♦  Staring at lights or spinning objects

   ♦  Ritualistic behaviors (e.g. lining up objects, repeatedly touching objects in a set order)

   ♦  Narrow or extreme interests in specific topics

   ♦  Need for unvarying routine/resistance to change (e.g. same daily schedule, meal menu, clothes, route to school

The autism spectrum is very wide. Some people might have very noticeable issues, others might not. The common thread is differences in social skills, communication, and behavior compared with people who aren’t on the spectrum.


Unfortunately, there's no 'cure' for autism spectrum disorder (ASD), but there are a range of specialist interventions that aim to improve communication skills and help with educational and social development. It can be difficult to know which intervention will work best for your child, because each person with ASD is affected differently. Some types of intervention can involve hours of intensive work, and this isn't always possible for many families because of the practical, emotional and financial commitments necessary. The goal of treatment is to maximize your child's ability to function by reducing autism spectrum disorder symptoms and supporting development and learning.

The range of home-based and school-based treatments and interventions for autism spectrum disorder can be overwhelming, and your child's needs may change over time. Your health care provider can recommend options and help identify resources in your area.

If your child is diagnosed with autism spectrum disorder, talk to experts about creating a treatment strategy and build a team of professionals to meet your child's needs.

Any intervention should focus on important aspects of your child's development. These are:

   ♦  Communication skills – such as using pictures to help communicate (as speech and language skills are usually significantly delayed)

   ♦  Social interaction skills – such as the ability to understand other people's feelings and respond to them

   ♦  Imaginative play skills – such as encouraging pretend play

   ♦  Academic skills – the "traditional" skills a child needs to progress with their education, such as reading, writing and maths.

Treatment options may include:

1. Parent education and training

The parents of a child with ASD play a crucial role in supporting their child and improving their skills. If your child has ASD, it's a good idea to find out as much as you can about the condition.

Communication advice for parents
Communication is particularly challenging for children with ASD. Helping your child to communicate can reduce anxiety and improve behaviour. Parents and other family members can learn how to play and interact with their children in ways that promote social interaction skills, manage problem behavior, and teach daily living skills and communication.

Many programs address the range of social, language and behavioral difficulties associated with autism spectrum disorder. Some programs focus on reducing problem behavior and teaching new skills. Other programs focus on teaching children how to act in social situations or communicate better with others. Applied behaviour analysis (ABA) can help children learn new skills and generalize these skills to multiple situations through a reward-based motivation system.

The following tips may be useful when communicating and interacting with your child:

   ♦  Use your child's name, so they know you're addressing them

   ♦  Keep background noise to a minimum

   ♦  Keep language simple

   ♦  Speak slowly and clearly, with pauses between words

   ♦  Accompany what you say with simple gestures

   ♦  Allow extra time for your child to process what you've said

2. Psychosocial treatments

If your child's behaviour is causing problems, they'll be assessed for possible triggers, such as a physical health condition, mental health problem, or environmental factors. A physical or mental cause will be addressed using medication and/or psychological treatments.

In some cases, such as where a child with ASD also has an anxiety problem, a psycho social treatment may also be recommended. These are supportive treatments that help people overcome challenges and maintain good mental health.

3. Educational therapies

Children with autism spectrum disorder often respond well to highly structure educational programs. Successful programs typically include a team of specialists and a variety of activities to improve social skills, communication and behaviour. Preschool children who receive intensive, individualized behavioral interventions often show good progress.

4. Medication

No medication can improve the core signs of autism spectrum disorder, but specific medications can help control symptoms. For example, certain medications may be prescribed if your child is hyperactive; anti-psychotic drugs are sometimes used to treat severe behavioral problems; and antidepressants may be prescribed for anxiety. Keep all health care providers updated on any medications or supplements your child is taking. Some medications and supplements can interact, causing dangerous side effects. In some cases, medication may be prescribed to treat some of the symptoms or conditions associated with ASD. For example:

   ♦  Sleeping problems – this may be treated with a medication such as melatonin

   ♦  Depression – this may be treated with a type of medication known as a Selective Serotonin Reuptake Inhibitor (SSRI)

   ♦  Epilepsy – this may be treated with a type of medication called an anticonvulsant

   ♦  Attention Deficit Hyperactivity Disorder (ADHD) – this may be treated with a medication such as methylphenidate

   ♦  Aggressive and challenging behaviour, such as tantrums or selfharming – this may be treated with a type of medication called an anti-psychotic if the behaviour is severe or psychological treatments haven't helped

   ♦  These medications can have significant side effects and are usually only prescribed by a doctor who specialises in the condition being treated. If medication is offered, your child will have regular check-ups to assess whether it's working.


As conclusion a diagnosis of autism can be overwhelming. For some people, it can even be frightening. But it's important to know that it is more than possible to live well with autism. Because autism is a spectrum disorder, it is possible to be mildly, moderately, or severely autistic. Confusingly, you can also have a combination of mild and severe symptoms. For example, it is possible to be very intelligent and verbal but also have severe symptoms of anxiety and sensory dysfunction.

It is important to know that autism is neither a mental illness nor a condition that gets worse over time. In fact, almost every autistic person grows and matures over time, particularly with intensive treatment. By the same token, however, there is no established cure for autism. This means that a child diagnosed with autism will almost certainly grow up to be an adult with autism with the challenges and strengths that come along with the diagnosis.


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