Autism Spectrum
Disorder
What is Autism Spectrum Disorder (ASD)?
Autism Spectrum Disorder (ASD), referred to as Autism, is a complex, lifelong developmental condition that typically appears during early childhood and can impact a person’s social skills, communication, relationships, and self-regulation. The Autism experience is different for everyone. It is defined by a certain set of behaviors and is often referred to as a “spectrum condition” that affects people differently and to varying degrees.
While there is no known single cause of Autism, early diagnosis helps a person receive resources to support the choices and opportunities needed to live fully.
Signs & Characteristics
Autism impacts an individual throughout their lifespan. However, research shows that early diagnosis can improve their quality of life. The behaviors of Autism may be apparent in infancy, but they usually become clearer during early childhood. As part of a regular health visit, your child’s doctor should perform developmental screenings focused on Autism. This screening is recommended at ages 18 and 24 months for all children.
Your doctor will encourage you to ask specific questions about your child’s developmental progress. The National Institute of Child Health and Human Development (NICHD) developed a detailed list of behaviors, listed in four categories: communication, social behavior, stereotyped behavior, and other behavior. Additionally, the Centers for Disease Control and Prevention (CDC) developed a list of Signs and Symptoms, which can be found here.
Causes & Factors
There is no known single cause for Autism, but it is generally accepted that differences in brain structure or function cause it. Brain scans show differences in the shape and structure of the brain in Autistic people compared to neurotypical development. Researchers do not know the exact cause of Autism but are investigating several theories, including the links among heredity, genetics, and medical problems.
In many families, there appears to be a pattern of Autism or related disabilities, further supporting the theory that the disorder has a genetic basis.
While no one gene has been identified as causing Autism, researchers are searching for irregular segments of genetic code that people with Autism may have inherited. It also appears that some people are born with a susceptibility to Autism, but researchers have not yet identified a single “trigger” that causes Autism to develop.
Other researchers are investigating the possibility that under certain conditions, a cluster of genes may affect brain development, resulting in Autism. Still, other researchers are investigating complications during pregnancy or delivery and environmental factors such as viral infections, metabolic imbalances, and chemical exposure.
Genetic Vulnerability
Autism tends to occur more frequently than expected among individuals who have certain medical conditions, including fragile X syndrome (FXS), tuberous sclerosis, congenital rubella syndrome (CRS), and untreated phenylketonuria (PKU). Some harmful substances ingested during pregnancy also have been associated with an increased likelihood of Autism.