Autism Spectrum Disorders

Autism spectrum disorder is a developmental disorder that begins in childhood and lasts throughout a person's life. It affects how a person acts and interacts with others, communicates, and learns.

Autism Spectrum Disorders Overview

Reviewed: May 8, 2014
Updated: 

Autism spectrum disorders (ASD) comprise neurological and developmental disorders that begin early in childhood, generally before age 3, and lasts throughout a person's life. ASD impacts the normal development of the brain in the areas of social interaction, communication skills, and cognitive function. Individuals with autism typically have difficulties in verbal and non-verbal communication, social interactions, and leisure or play activities.

It is called a "spectrum" disorder because people with ASD can have a range of symptoms. People with ASD might have problems talking and communicating with others, or they may have restricted interests and repetitive behaviors.

Individuals with ASD often suffer from numerous other medical conditions including allergies, asthma, epilepsy, digestive disorders, persistent viral infections, feeding disorders, sensory integration dysfunction, and sleeping disorders.

Boys are 4 times more likely to be diagnosed with ASD than girls. ASD occurs in people of all races, regions, and socio-economic statuses.

The causes of ASD are not known. Research suggests that both genes and environment play important roles.

There is currently no single standard treatment for ASD, partly because the symptoms are so diverse, but there are many ways to increase a person’s ability to grow and learn new skills even with ASD. Starting therapy early can lead to better results. Treatments include behavior and communication therapies, skills training, and medicines to control certain symptoms.

Autism Spectrum Disorders Symptoms

ASD varies from person-to-person and no 2 people will show the same symptoms. The hallmark feature of ASD is impaired social interaction. As early as infancy, a baby with ASD may be unresponsive to people or focus intently on one item to the exclusion of others for long periods of time. A child with ASD may appear to develop normally and then withdraw and become indifferent to social engagement.

Children with an ASD may fail to respond to their names and often avoid eye contact with other people. They have difficulty interpreting what others are thinking or feeling because they do understand social cues, such as tone of voice or facial expressions, and they do not watch other people’s faces for clues about appropriate behavior. They may lack empathy.

Many children with ASD engage in repetitive movements such as rocking and twirling, or in self-abusive behavior such as biting or head-banging. Children with ASD tend to start speaking later than other children and they do not play or interact with other children.

Children with symptoms of ASD may have other medical conditions, including Fragile X syndrome (which causes intellectual disability), tuberous sclerosis, epileptic seizures, Tourette syndrome, learning disabilities, and attention deficit disorder.

Autism Spectrum Disorders Causes

The exact causes of ASD are not known, but it’s likely that both genetics and environment play a role. Researchers have identified a number of genes associated with the disorder, and studies of people with ASD have found irregularities in several regions of the brain. Other studies have suggested that abnormal levels of serotonin or other neurotransmitters in the brain are associated with ASD. All of these findings are preliminary and require further study. Parental practices do not cause ASD.

Autism Spectrum Disorders Diagnosis

ASD varies widely in severity and symptoms and ASD may go unrecognized, especially in children who demonstrate only mild symptoms. Early indicators that require evaluation by an expert include:

  • no babbling or pointing by age 1
  • no single words by 16 months or two-word phrases by age 2
  • no response to name
  • loss of language or social skills
  • poor eye contact
  • excessive lining up of toys or objects
  • no smiling or social responsiveness

Later indicators of ASD include:

  • impaired ability to make friends with peers
  • impaired ability to initiate or sustain a conversation with others
  • absence or impairment of imaginative and social play
  • stereotyped, repetitive, or unusual use of language
  • restricted patterns of interest that are abnormal in intensity or focus
  • preoccupation with certain objects or subjects
  • inflexible adherence to specific routines or rituals

Health care providers will often use a questionnaire or other screening instrument, which rely on parent, care giver, and health care provider observations, to gather information about a child’s development and behavior. If screening instruments indicate the possibility of an ASD, a more comprehensive evaluation is usually indicated.

A comprehensive evaluation includes a multidisciplinary team, including a psychologist, neurologist, psychiatrist, speech therapist, and other professionals who diagnose children with ASDs. The team members conduct a thorough neurological assessment and in-depth cognitive and language testing to rule out hearing problems or other developmental disorders that cause behaviors that can be mistaken for an ASD.

Living With Autism Spectrum Disorders

For many children, symptoms improve with treatment and with age. During adolescence, some children with an ASD may become depressed or experience behavioral problems, and their treatment may need some modification as they transition to adulthood. People with an ASD usually continue to need services and supports as they get older, but many are able to work successfully and live independently or within a supportive environment.

Autism itself does not affect life expectancy. However, the risk of mortality among individuals with ASD is twice as high as the general population, in part due to drowning and other accidents.

Autism Spectrum Disorders Treatments

There is no cure for ASD. The goal of therapies and behavioral interventions is to improve specific symptoms. The ideal treatment plan will include therapies and interventions that are individualized to meet the specific needs of each person with ASD. Approaches to therapy include:

  • Educational/behavioral interventions. Intensive skill-oriented training sessions help children develop social and language skills, and family counseling for the parents and siblings of children with an ASD often helps families manage the challenges of living with a child with an ASD. Occupational therapy, physical therapy, speech therapy, and music therapy are also possible therapies that can be part of a complete treatment plan for ASD.
  • Medications. Doctors may prescribe medications for the treatment of specific autism-related symptoms, such as anxiety, depression, or obsessive-compulsive disorder. Selective serotonin reuptake inhibitors, such as fluoxetine (Prozac), fluvoxamine (Luvox), sertraline (Zoloft), and clomipramine (Anafranil) can be used to control anxiety, depression, and obsession-compulsive disorder in children. Antipsychotic medications, such as haloperidol (Haldol), olanzapine (Zyprexa), risperidone (Risperdal), and ziprasidone (Geodon), are used to treat severe behavioral problems. Seizures can be treated with one or more anticonvulsant drugs, such as carbamazepine (Tegretol), lamotrigine (Lamictal), topiramate (Topamax), and valproic acid (Depakote). Medications usually used to treat people with attention deficit hyperactivity disorder, such as methylphenidate (Ritalin, Concerta, Focalin), can also be used to help decrease impulsivity and hyperactivity in children with ASD.

Several controversial therapies or interventions are available for ASD, but few, if any, are supported by scientific studies. Parents should use caution before adopting any unproven treatments. Although dietary interventions have been helpful in some children, parents must be aware of their child’s overall health and nutritional status.