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Autism Spectrum Disorder

What is Autistic Spectrum Disorder?

Autism Spectrum Disorder (ASD) is a complex neurological and developmental disorder that begins early in life and affects how a person acts and interacts with others, communicates, and learns. ASD affects the structure and function of the brain and nervous system. Because it affects development, ASD is called a developmental disorder. It can last throughout a person’s life.

ASD is characterized to varying degrees by difficulties in social interaction, issues with verbal and nonverbal communication, and repetitive behaviors. With the May 2013 publication of the DSM-5 diagnostic manual, all autism disorders were merged into one umbrella diagnosis of ASD. Previously, they were recognized as distinct subtypes, including autistic disorder, childhood disintegrative disorder, pervasive developmental disorder – not otherwise specified (PDD-NOS) and Asperger syndrome.

It is considered a spectrum disorder because there is a wide range of symptoms, skills and levels of impairment or disability among people with the disorder. Usually first diagnosed in early childhood, ASD causes severe and pervasive impairment in thinking, feeling, language, and the ability to relate to others. The disorder also can be associated with intellectual disability, difficulties in motor coordination and attention and physical health issues such as sleep and gastrointestinal disturbances. Some persons with ASD excel in visual skills, music, math and art. About 25 percent of those with ASD are nonverbal but can learn to communicate using other means.

How common is Autism?

ASD affects more than 3 million individuals in the U.S. and tens of millions worldwide. Moreover, government autism statistics suggest that prevalence rates have increased 10 to 17 percent annually in recent years. A survey by the U.S. Centers for Disease Control and Prevention (CDC) that examined health and school records of 8-year-olds in 11 communities throughout the country found that approximately 1 in 68 children in 2010 was on the autism spectrum. Boys face about four to five times higher risk than girls, with 1 in 42 boys diagnosed with ASD versus one in 189 girls. The CDC report confirms other recent studies that reveal more children are being diagnosed with ASD than ever before – a ten-fold increase in prevalence in 40 years.

Signs and Symptoms

Autism spectrum disorder (ASD) is characterized by the following criteria:

  • Persistent deficits in social communication and social interaction across multiple contexts;
  • Restricted, repetitive patterns of behavior, interests or activities;
  • Symptoms present in the early developmental period (typically recognized in the first two years of life); and,
  • Symptoms cause clinically significant impairment in social, occupational or other important areas of current functioning.

Autism appears to have its roots in very early brain development. The most obvious signs of autism and symptoms of autism tend to emerge between 2 and 3 years of age, however many children show symptoms of autism by 12 months to 18 months of age. These may include:

  • Problems with eye contact
  • No response to his or her name
  • Problems following another person’s gaze or pointed finger to an object
  • Poor skills in pretend play and imitation
  • Problems with nonverbal communication

Many parents are not aware of these “early” signs of autism and don’t start thinking about autism until their children do not start speaking at a typical age. Children with autism do not progress through normal stages of child development. Some children show signs of future issues once they’re born. Other children may develop typically until they’re 18-36 months old, and then development stalls: When an affectionate, babbling toddler suddenly becomes silent, withdrawn, self-abusive, or indifferent to social overtures, something is wrong.

People with autism tend to appear indifferent and remote and are unable to form emotional bonds with others. In addition, they will often have unusual responses to sensory experiences, such as certain sounds or the way objects look. Symptoms can range from mild to severe depending on the individual.


Diagnosis of autism spectrum disorder (ASD) is often a two-stage process. The first stage involves general developmental screening during well-child checkups with a pediatrician or an early childhood health care provider. Children who show some developmental problems are referred for additional evaluation. The second stage involves a thorough evaluation by a team of doctors and other health professionals with a wide range of specialties. At this stage, a child may be diagnosed as having ASD or another developmental disorder.

Because ASD is a complex disorder that sometimes occurs along with other illnesses or learning disorders, the comprehensive evaluation may include brain imaging and gene tests, along with in-depth memory, problem-solving and language testing.


Currently, there is no proven cure for autism spectrum disorder. However, treating ASD early, using school-based programs, and getting proper medical care can greatly reduce ASD symptoms and increase the child’s ability to grow and learn new skills.

Behavioral interventions

Early intervention is crucial: Research has shown that intensive behavioral therapy during the toddler or preschool years can significantly improve cognitive and language skills in young children with ASD. Even though there isn’t a single-best treatment package for all children with ASD, they respond well to highly structured, specialized programs. Among the many methods available for treatment and education of people with autism, applied behavior analysis (ABA) is effective in helping those with ASD control their behavior.


At this time, the only medications approved by the FDA to treat aspects of ASD are the antipsychotics risperidone (Risperdal) and aripripazole (Abilify). These medications can help reduce irritability—specifically aggression, self-harming acts, or temper tantrums—in children ages 5 to 16 who have ASD. Additional drugs are often used to help improve symptoms of autism, although not specifically approved by the FDA for this purpose. These can include other antispychotics, as well as antidepressant and stimulant medications.

Co-Occurring Conditions

Children with ASD can also develop mental disorders such as anxiety disorders, attention deficit hyperactivity disorder (ADHD) or depression. Research shows that people with ASD are at higher risk for some mental disorders than people without ASD. Managing these co-occurring conditions with medications or behavioral therapy can reduce symptoms that appear to worsen a child’s ASD symptoms. Controlling these conditions allows children with ASD to focus more on managing the ASD.