Autism is characterized by impaired social interaction, problems with verbal and nonverbal communication, unusual, repetitive, or severely limited activities and interests. Males are four times more likely to have autism than females. It is estimated that three to six out of every 1,000 children in the United States have autism, and the number of diagnosed cases is rising. It is still not clear whether this is due to better detection and reporting of autism, a real increase in the number of cases, or both.
Common Signs of Autism
There are three distinctive behaviors that characterize autism. Autistic children have difficulties with social interaction, problems with verbal and nonverbal communication, and repetitive behaviors or narrow, obsessive interests. These behaviors can range in impact from mild to disabling. The hallmark feature of autism is impaired social interaction. Parents are usually the first to notice symptoms of autism in their child.
As early as infancy, a baby with autism may be unresponsive to people or focus intently on one item to the exclusion of others for long periods of time. A child with autism may appear to develop normally and then withdraw and become indifferent to social engagement. They may also fail to respond to their name and often avoid eye contact with other people.
Autistic children have difficulty interpreting what others are thinking or feeling because they cannot understand social cues, such as tone of voice or facial expressions, and do not watch other people’s faces for clues about appropriate behavior. Many children with autism engage in repetitive movements such as rocking and twirling, or in self-abusive behavior such as biting or head-banging.
These children may not know how to play interactively with other children. Some speak in a sing-song voice about a narrow range of favorite topics, with little regard for the interests of the person to whom they are speaking. They have a reduced sensitivity to pain, but are abnormally sensitive to sound, touch, or other sensory stimulation. These unusual reactions may contribute to behavioral symptoms such as a resistance to being cuddled or hugged.
Those born with the disorder appear to have a higher than normal risk for certain co-existing conditions, including fragile X syndrome (which causes mental retardation), tuberous sclerosis (in which tumors grow on the brain), epileptic seizures, Tourette syndrome, learning disabilities, and attention deficit disorder. For reasons that are still unclear, about 20 to 30 percent of children with autism develop epilepsy by the time they reach adulthood.
How is Autism diagnosed?
Autism varies widely in its severity and symptoms and may go unrecognized, especially in mildly affected children or when it is masked by more debilitating handicaps. Specialists rely on a core group of behaviors to alert them to the possibility of a diagnosis of autism as provided for by The DSM-IV-TR 299.00, these behaviors are:
- 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
Practitioners will often use a questionnaire or other screening instrument to gather information about a child’s development and behavior. Some screening instruments rely solely on parent observations; others rely on a combination of parent and doctor observations. If screening instruments indicate the possibility of autism, a more comprehensive evaluation will be required.
Autism is a complex disorder. A comprehensive evaluation requires a multidisciplinary team including a psychologist, neurologist, psychiatrist, speech therapist, and other professionals who diagnose children with ASDs. The team members will conduct a thorough neurological assessment and in-depth cognitive and language testing. Because hearing problems can cause behaviors that could be mistaken for autism, children with delayed speech development should also have their hearing tested. After a thorough evaluation, the team usually meets with parents to explain the results of the evaluation and present the diagnosis.
Children with some symptoms of autism, but not enough to be diagnosed with classical autism are often diagnosed with Pervasive Developmental Disorder not otherwise specified (PDD-NOS) as provided for in the DSM-IV-TR 299.80. Those with autistic behaviors but well-developed language skills are often diagnosed with Asperger’s Disorder also under DSM-IV-TR 299.80 while those who develop normally and then suddenly deteriorate between the ages of 3 to 10 years and show marked autistic behaviors may be diagnosed with Childhood Disintegrative Disorder per DSM-IV-TR 299.10.
Girls with autistic symptoms may be suffering from Rett syndrome, a sex-linked genetic disorder characterized by head growth deceleration, social withdrawal, regressed language skills, and hand wringing, DSM-IV-TR 299.80.
Causes of Autism
Scientists are not certain what causes autism, but it’s likely that both genetics and environment play a role. Researchers have identified a number of genes associated with the disorder. Studies of people with autism have found irregularities in several regions of the brain. Other studies suggest that people with autism have abnormal levels of serotonin or other neurotransmitters in the brain.
These abnormalities suggest that autism could result from the disruption of normal brain development early in fetal development caused by defects in genes that control brain growth and that regulate how neurons communicate with each other. These are however preliminary findings and require further study.
As regards environmental factors researchers are currently exploring whether viral infections and air pollutants, for instance, play a role in triggering autism. Other factors under investigation include problems during labor and delivery and the role of the immune system in autism. Some researchers believe that damage to the amygdala, a portion of the brain that serves as a danger detector, may play a role in autism.
One of the greatest controversies in autism centers on whether a link exists between autism and certain childhood vaccines, particularly the measles-mumps-rubella (MMR) vaccine and vaccines with thimerosal, a preservative that contains a small amount of mercury. Though most children’s vaccines have been free of thimerosal since 2001, the controversy continues.
To date, extensive studies have found no link between autism and vaccines and in February 2009 a special federal court ruled that there was no proven link between certain early childhood vaccines and autism that developed in three children.
Recent studies strongly suggest that some people have a genetic predisposition to autism. In families with one autistic child, the risk of having a second child with the disorder is approximately 5 percent, or one in 20. This is greater than the risk for the general population. Researchers are looking for clues about which genes contribute to this increased susceptibility.
In some cases, parents and other relatives of an autistic child show mild impairments in social and communicative skills or engage in repetitive behaviors. Evidence also suggests that some emotional disorders, such as manic depression, occur more frequently than average in the families of people with autism.
Treatment and Drugs
There is no cure for autism. Therapies and behavioral interventions are designed to remedy specific symptoms and can bring about substantial improvement. The ideal treatment plan coordinates therapies and interventions that target the core symptoms of autism: impaired social interaction, problems with verbal and nonverbal communication, and obsessive or repetitive routines and interests. Most professionals agree that the earlier the intervention, the better.
Educational/behavioral interventions: Therapists use highly structured and intensive skill oriented training sessions to help children develop social and language skills. Behavioral training and management will apply positive reinforcement, self-help, and social skills training to improve behavior and communication. Many types of treatments have been developed, including Applied Behavioral Analysis (ABA), Treatment and Education of Autistic and Related Communication Handicapped Children (TEACCH), and sensory integration.
Specialized therapies: These include speech, occupational, and physical therapy. Speech therapy can help a child with autism improve language and social skills to communicate more effectively. Occupational and physical therapy can help improve any deficiencies in coordination and motor skills. Occupational therapy may also help a child with autism to learn to process information from the senses (sight, sound, hearing, touch, and smell) in more manageable ways. Family counseling for the parents and siblings of children with autism often helps families cope with the challenges of living with an autistic child.
Medications: Doctors often prescribe an antidepressant medication to handle symptoms of anxiety, depression, or obsessive-compulsive disorder. Anti-psychotic medications are used to treat severe behavioral problems. Seizures can be treated with one or more of the anticonvulsant drugs. Stimulant drugs, such as those used for children with attention deficit disorder (ADD), are sometimes used effectively to help decrease impulsivity and hyperactivity.