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Autism Spectrum Disorders

What Are Autism Spectrum Disorders (ASD)?

Fast Facts

  • Autism Spectrum Disorders (ASD) are a group of developmental brain disorders. They can cause major social, communication, and behavioral challenges.
  • The Centers for Disease Control and Prevention (CDC) estimates approximately 1 in 88 children in the United States has an ASD.
  • ASDs begin before age three. They last for life, although symptoms may improve over time.
  • ASDs occur in all racial, ethnic, and socioeconomic groups. They are almost five times as common among boys as girls.
  • The main research-based treatment for ASDs is behavioral intervention. This involves structured teaching of skills. It is very important to begin as early as possible in order to help a child reach his or her full potential.

Autism is a group of brain development disorders. They are also called autism spectrum disorders (ASD) because of the wide range of symptoms, skills, and levels of impairment, or disability, that children with ASD can have. Symptoms usually start before age three. They can delay or cause problems in many different skills that develop from infancy to adulthood. The main signs and symptoms of autism involve problems with communication, social interactions, and repetitive behaviors.


Symptoms of autism spectrum disorders (ASD) vary from child to child but generally fall into three areas:

  • Communication—both verbal (spoken) and non-verbal (unspoken, such as pointing, eye contact, and smiling)
  • Social—such as sharing emotions, understanding how others think and feel, and holding a conversation
  • Routines or repetitive behaviors (also called stereotyped behaviors)—such as repeating words or actions, obsessively following routines or schedules, and playing in repetitive ways

Children with ASD do not follow typical patterns of development when it comes to social and communication skills. Parents are usually the first to notice this. Often, certain behaviors become more noticeable when they compare their children to others of the same age.

In some cases, babies with ASD may seem very different early in their development. Even before their first birthdays, some become overly focused on certain objects, rarely make eye contact, and fail to engage in typical back-and-forth play and babbling with their parents. Other babies may develop normally until they are two or three, but then start to lose interest in others. They become silent, withdrawn, or indifferent to social signals.

Some Types of ASD

  • Autistic disorder (classic autism): This is what most people think of when hearing the word "autism." People with autistic disorder usually have major language delays, social and communication challenges, and unusual behaviors and interests. Many also have intellectual disability.
  • Asperger's disorder (Asperger syndrome): People with Asperger syndrome might have social challenges and unusual behaviors and interests. However, they typically do not have problems with language or intellectual disability.
  • Pervasive developmental disorder not otherwise specified (PDD-NOS): People who meet some of the criteria for autistic disorder or Asperger syndrome, but not all, may be diagnosed with PDD-NOS. They may have only social and communication challenges.

Social Impairment

Most children with ASD have trouble engaging in everyday social interactions. They may:

  • Make little eye contact
  • Tend to look and listen less to people in their regular environment or fail to respond to other people
  • Not readily seek to share their enjoyment of toys or activities by pointing or showing things to others
  • Respond unusually when others show anger, distress, or affection
Child with teacher

A therapist works with a child with autism doing ABA (Applied Behavioral Analysis) therapy.

Communication Issues

By their first birthdays, typical toddlers can say one or two words, turn when they hear their names, and point when they want a toy, according to the American Academy of Pediatrics' developmental milestones. When offered something they do not want, they make it clear through words, gestures, or facial expressions that the answer is "no."

Children with ASD may have trouble reaching such milestones. For example, some may:

  • Fail or be slow to respond to their names or other verbal attempts to gain their attention
  • Fail or be slow to develop gestures, such as pointing and showing things to others
  • Coo and babble in the first year of life, but then stop
  • Develop language at a delayed pace
  • Learn to communicate using pictures or their own sign language
  • Speak only in single words or repeat certain phrases over and over
  • Repeat words or phrases that they hear, a condition called echolalia
  • Use words that seem odd, out of place, or have special meaning known only to those familiar with the child's way of communicating.


Children with ASD often have repetitive motions or unusual behaviors. For example, some children may repeatedly flap their arms or walk in specific patterns. Others may subtly move their fingers by their eyes in what looks to be a gesture. These repetitive actions are called "stereotyped behaviors."

Children with ASD also tend to have overly focused interests. They may become fascinated with moving objects or parts of objects, like the wheels on a moving car. They might spend a long time lining up toys in a certain way, rather than playing with them. They may also become very upset if someone accidentally moves one of the toys. Children with ASD often have great interest in numbers, symbols, or science topics.

Children with ASD:

  • might have problems learning to talk or having a conversation
  • might not look people in the eye when talking
  • may have to line up toys or other objects before they can pay attention
  • may say the same sentence again and again to calm themselves down
  • may flap their arms or flick their fingers to tell others they are happy, sad, or anxious
  • might hurt themselves to tell others they are not happy.

Children with ASD may vary from mildly impaired to severely disabled. Some people with autism never learn how to talk.

How Common Is ASD?

There are various estimates of the number of children with ASD. A Center for Disease Control and Prevention (CDC) survey found that around 1 in 88 children has ASD. Although higher than in previous studies, experts disagree whether this shows a true increase in ASD. This is because guidelines for diagnosis have changed. Also, many more parents and doctors now know about ASD, so parents are more likely to have their children diagnosed. Boys are at four to five times greater risk than girls.

Read More "Autism Spectrum Disorder" Articles

Dan Marino Helping Those with Autism Spectrum Disorders / What Are Autism Spectrum Disorders (ASD)? / Diagnosis, Treatment & Research

Winter 2013 Issue: Volume 7 Number 4 Page 18-19