Autism Symptoms, Causes, Treatment, and More

Autism belongs to a group of developmental disabilities called autism spectrum disorders (ASD). The name "spectrum" stems from the fact that these disorders affect each child differently. These disorders involve delays in the development of many basic skills, including the abilities to socialize or form relationships with others and to communicate effectively. Children with autism may also have intellectual disabilities and behavioral challenges.

What Are the Symptoms of Autism Spectrum Disorders?

Symptoms of autism spectrum disorders typically appear before a child reaches age 3 and last throughout life. Children with ASD can display a wide range of symptoms, which can vary in severity from mild to disabling. General symptoms that may be present to some degree in a child with autism include:

  • Difficulty with verbal communication, including problems using and understanding language
  • Inability to participate in a conversation, even when the child has the ability to speak
  • Difficulty with non-verbal communication, such as gestures and facial expressions
  • Difficulty with social interaction, including relating to people and to his or her surroundings
  • Difficulty making friends and preferring to play alone
  • Unusual ways of playing with toys and other objects, such as only lining them up a certain way
  • Difficulty adjusting to changes in routine or familiar surroundings, or an unreasonable insistence on following routines in detail
  • Repetitive body movements, or patterns of behavior, such as hand flapping, spinning, and head banging
  • Preoccupation with unusual objects or parts of objects

People with a form of autism, called autistic savantism, have exceptional skills in specific areas, such as music, art, and numbers. People with this form of autism are able to perform these skills without lessons or practice.

What Are the Warning Signs That a Child May Have Autism Spectrum Disorders?

Babies develop at their own pace, some more quickly than others. However, you should consider an evaluation for autism if any of the following apply:

  • Your child does not babble or coo by 12 months of age (cooing typically starts when a child is 2 months old)
  • Your child does not gesture, such as point or wave, by 12 months of age
  • Your child does not say single words by 16 months
  • Your child does not say two-word phrases on his or her own (rather than just repeating what someone else says) by 24 months
  • Your child has lost any language or social skills (at any age)
  • Your child does not establish or maintain eye contact
  • Your child does not make facial expressions or respond to your facial expressions


What Causes Autism Spectrum DIsorders?

The exact cause of ASD is not known, but research has pointed to several possible factors, including genetics (heredity), metabolic or neurological factors, certain types of infections, and problems occurring at birth.

Recent studies strongly suggest that some people have a genetic predisposition to autism, meaning that a susceptibility to develop the condition may be passed on from parents to children. Researchers are looking for clues about which genes contribute to this increased vulnerability. In some children, environmental factors may also play a role. Studies of people with autism have found abnormalities in several regions of the brain, which suggest that autism results from a disruption of early brain development while still developing in the mother's womb.

Other autism theories suggest:

  • The body's immune system may inappropriately produce antibodies that attack the brains of children, causing autism. This theory is not widely thought of as being valid.
  • Abnormalities in brain structures cause autistic behavior.
  • Children with autism have abnormal timing of the growth of their brains. Early in childhood, the brains of children with autism grow faster and larger than those of normal children. Later, when normal children's brains get bigger and better organized, the brains of kids with autism grow more slowly.

Can Childhood Vaccines Cause Autism?

To date, there is no evidence that any vaccine can cause autism or any kind of behavioral disorder. A suspected link between the measles, mumps, rubella (MMR) vaccine and autism was suggested by some parents of children with autism, but well-documented, wide-ranging studies have discounted any association. One basis for the rejection of the theory is that typically, symptoms of autism are first noted by parents as their child begins to have difficulty with delays in speaking after age one. The MMR vaccine is first given to children at 12 to 15 months of age; autism cases with an apparent onset within a few weeks after the MMR vaccination may simply be an unrelated chance occurrence.

Speculation that a preservative used in vaccines, thimerosol, is responsible for an increase in autism cases has also led to studies that have shown no evidence of a link.


How Common Is Autism Spectrum Disorders?

Autism and related disorders affect an estimated 1 in 68 children. According to the CDC, more children today are diagnosed with ASD than ever before. Experts aren't sure if autism is getting more common or if doctors are just better at diagnosing the disorders.

How Is ASD Diagnosed?

If autism spectrum disorders symptoms are present, the doctor will begin an evaluation by performing a complete medical history and physical and neurological exam. Although there are no laboratory tests for autism, the doctor may use various tests -- such as X-rays and blood tests -- to determine if there is a physical, genetic, or metabolic disorder causing the symptoms.

If no physical disorder is found, the child may be referred to a specialist in childhood development disorders, such as a child and adolescent psychiatrist or psychologist, pediatric neurologist, developmental-behavioral pediatrician, or another health professional who is specially trained to diagnose and treat autism. The doctor bases his or her diagnosis on the child's level of development, and the doctor's observation of the child's speech and behavior, including his or her play and ability to socialize with others. The doctor often seeks input from the child's parents, teachers, and other adults who are familiar with the child's symptoms.

Subtypes of Autism Spectrum Disorder Include:


How Is Autism Treated?

There currently is no cure for autism, but treatment may allow for relatively normal development in the child and reduce undesirable behaviors. Children with autism generally benefit most from a highly structured environment and routines. Treatment for autism may include a combination of the following:

  • Special education: Education is structured to meet the child's unique educational needs.
  • Behavior modification: This includes strategies for supporting positive behavior and decreasing problem behaviors.
  • Speech, physical, or occupational therapy: These therapies are designed to increase the child's functional abilities.
  • Social skills therapies : These therapies address language and social pragmatics in those verbal individuals with autism.
  • Medication: There are no medications currently approved to treat autism, but medications may be used to treat certain symptoms, such as anxiety, hyperactivity, sleep disturbance, and other behaviors that may lead to injury.


What Is the Outlook for People With Autism?

The outlook for people with autism varies depending on the severity of symptoms, the age at which treatment is started, and the availability of supportive resources for the child. Symptoms in many children improve with intervention or with age. Some people with autism are able to lead normal or near-normal lives. Some severely affected children may not develop enough functional and communication skills to live independently as adults. The outlook is better for children with higher levels of intelligence who are able to communicate with language.

What Autism Research Is Being Done?

The National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health, is studying brain abnormalities that may cause autism and is looking for genes that may increase the risk of autism. Researchers also are investigating possible biologic markers present at birth that can identify infants at risk for developing autism. Other studies are examining how different brain regions develop and function in relation to each other, and how alterations in these relationships may result in the signs and symptoms of autism. Researchers hope these studies will provide new clues about how autism develops and how brain abnormalities affect behavior.

Can Autism Be Prevented?

There is no known way to prevent or cure autism. However, early diagnosis and intervention is critical and may help to maximize a child's ability to speak, learn, and function. It is very important that all children see a pediatrician regularly so that any signs of autism can be detected early.


WebMD Medical Reference Reviewed by Smitha Bhandari, MD on May 30, 2016



National Institutes of Health. 

U.S. Food and Drug Administration. 


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