Autism is a developmental disorder characterized by difficulties with social interaction and communication, and by restricted and repetitive behavior. Parents usually notice signs during the first three years of their child’s life. These signs often develop gradually, though some children with autism reach their developmental milestones at a normal pace before worsening.
Symptoms of Autism
Trouble with social interaction, impaired communication, restricted interests, repetitive behavior
Autism is associated with a combination of genetic and environmental factors. It has a affected 24.8 million people in 2015.
Risk factors during pregnancy include certain infections, such as rubella, toxins including valproic acid, alcohol, cocaine, pesticides and air pollution, fetal growth restriction, and autoimmune diseases.
Controversies surround other proposed environmental causes; for example, the vaccine hypothesis, which has been disproven. Autism affects information processing in the brain by altering connections and organization of nerve cells and their synapses. How this occurs is not well understood. In the DSM-5, autism and less severe forms of the condition, including Asperger syndrome and pervasive developmental disorder not otherwise specified (PDD-NOS), have been combined into the diagnosis of autism spectrum disorder (ASD).
Autistic individuals can display many forms of repetitive or restricted behavior, which the Repetitive Behavior Scale-Revised (RBS-R) categorizes as follows.]
Stereotyped behaviors: Repetitive movements, such as hand flapping, head rolling, or body rocking.
Compulsive behaviors: Time-consuming behaviors intended to reduce anxiety that an individual feels compelled to perform repeatedly or according to rigid rules, such as placing objects in a specific order, checking things, or hand washing.
Sameness: Resistance to change; for example, insisting that the furniture not be moved or refusing to be interrupted.
Ritualistic behavior: Unvarying pattern of daily activities, such as an unchanging menu or a dressing ritual. This is closely associated with sameness and an independent validation has suggested combining the two factors.
Restricted interests: Interests or fixations that are abnormal in theme or intensity of focus, such as preoccupation with a single television program, toy, or game.
Self-injury: Behaviors such as eye-poking, skin-picking, hand-biting and head-banging.
No single repetitive or self-injurious behavior seems to be specific to autism, but autism appears to have an elevated pattern of occurrence and severity of these behaviors
Infection with rubella during pregnancy causes fewer than 1% of cases of autism, vaccination against rubella can prevent many of those cases.
Autism spectrum disorder has no single known cause. Both genetics and environment may play a role.
- Genetics.For some children, autism spectrum disorder can be associated with a genetic disorder, such as Rett syndrome or fragile X syndrome.Other genes may affect brain development or the way that brain cells communicate, it can be inherited or occurs spontaneously.
- Environmental factors. Researchers are currently exploring whether factors such as viral infections, medications or complications during pregnancy, or air pollutants play a role in triggering autism spectrum disorder.
Autism spectrum disorder affects children of all races and nationalities, but certain factors increase a child’s risk. These may include
- Your child’s sex.Boys are more likely to develop autism spectrum disorder than girls are.
- Family history. Families who have one child with autism spectrum disorder have an increased risk of having another child with the disorder.
- Other disorders. Children with certain medical conditions have a higher than normal risk of autism spectrum disorder or autism-like symptoms.
- Extremely preterm babies. Babies born before 26 weeks of gestation may have a greater risk of autism spectrum disorder.
- Parents’ ages.Children born through Older parents will have connections with this disorder. However, more research is on to prove this.