Autism Spectrum Disorder

Overview

Autism spectrum disorder (ASD) is a neurological and developmental disorder that affects how people interact with others, communicate, learn, and behave. Although autism can be diagnosed at any age, it is described as a “developmental disorder” because symptoms generally appear in the first 2 years of life.

According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), a guide created by the American Psychiatric Association that health care providers use to diagnose mental disorders, people with ASD often have:

Difficulty with communication and interaction with other people
Restricted interests and repetitive behaviors
Symptoms that affect their ability to function 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.

People of all genders, races, ethnicities, and economic backgrounds can be diagnosed with ASD. Although ASD can be a lifelong disorder, treatments and services can improve a person’s symptoms and daily functioning. The American Academy of Pediatrics recommends that all children receive screening for autism. Caregivers should talk to their child’s health care provider about ASD screening or evaluation.

Signs and symptoms of ASD

The list below gives some examples of common types of behaviors in people diagnosed with ASD. Not all people with ASD will have all behaviors, but most will have several of the behaviors listed below.

Social communication / interaction behaviors may include:

Making little or inconsistent eye contact
Appearing not to look at or listen to people who are talking
Infrequently sharing interest, emotion, or enjoyment of objects or activities (including infrequent pointing at or showing things to others)
Not responding or being slow to respond to one’s name or to other verbal bids for attention
Having difficulties with the back and forth of conversation
Often talking at length about a favorite subject without noticing that others are not interested or without giving others a chance to respond
Displaying facial expressions, movements, and gestures that do not match what is being said
Having an unusual tone of voice that may sound sing-song or flat and robot-like
Having trouble understanding another person’s point of view or being unable to predict or understand other people’s actions
Difficulties adjusting behaviors to social situations
Difficulties sharing in imaginative play or in making friends

Restrictive / repetitive behaviors may include:

Repeating certain behaviors or having unusual behaviors, such as repeating words or phrases (a behavior called echolalia)
Having a lasting intense interest in specific topics, such as numbers, details, or facts
Showing overly focused interests, such as with moving objects or parts of objects
Becoming upset by slight changes in a routine and having difficulty with transitions
Being more sensitive or less sensitive than other people to sensory input, such as light, sound, clothing, or temperature

People with ASD may also experience sleep problems and irritability.

People on the autism spectrum also may have many strengths, including:

Being able to learn things in detail and remember information for long periods of time
Being strong visual and auditory learners
Excelling in math, science, music, or art

Causes and related factors

Researchers don’t know the primary causes of ASD, but studies suggest that a person’s genes can act together with aspects of their environment to affect development in ways that lead to ASD. Some factors that are associated with an increased likelihood of developing ASD include:

Having a sibling with ASD
Having older parents
Having certain genetic conditions (such as Down syndrome or Fragile X syndrome)
Having a very low birth weight

Source: https://www.nimh.nih.gov/health/topics/autism-spectrum-disorders-asd