Autism spectrum disorder (ASD) is a neurological and developmental condition marked by behaviors that can interfere with everyday function and create challenges for communication and social engagement. It can range in severity from mild to disabling.
ASD refers to a number of developmental conditions and disorders that used to be diagnosed separately, including autism, pervasive developmental disorder not otherwise specified (PDD-NOS), and Asperger syndrome.
1 in 54
Children diagnosed with autism by age 8
More boys diagnosed than girls
Age in childhood when it first appears
Researchers are not sure what causes autism, but they believe genetic and environmental factors play a role. Risk factors can include having older parents or a sibling with ASD, genetic or chromosomal conditions like Down syndrome or fragile X syndrome, and very low birth weight. ASD occurs in all racial, ethnic, and socioeconomic groups, but boys are four times more likely to be diagnosed than girls.
Brain imaging studies have shown that people on the autism spectrum may experience differences in brain development early in life, such as changes to the formation of the amygdala and corpus callosum. Some evidence points to a critical period before, during, and immediately after birth for developing ASD.
Coexisting conditions can include attention deficit hyperactivity disorder (ADHD), anxiety, depression, and epilepsy.
Autism Signs and Symptoms
Autism spectrum disorder varies widely in its severity and symptoms. Individuals with ASD have unique strengths, challenges, and needs, and cognitive and behavioral symptoms can range from mild to severe.
People with ASD may communicate, behave, interact, and learn in different ways than other people. They often have difficulty with social interaction, emotional skills, and verbal and nonverbal communication.
Early symptoms often include a significant delay in developing language or social skills. The behaviors associated with ASD usually appear within a child’s first 2 years. Children or adults with ASD may:
avoid eye contact or prefer to be alone
have trouble understanding or talking about feelings
have difficulty reading social cues (including tone, facial expressions, and body language)
show a narrow, intense focus on specific topics, interests, or objects
engage in repetitive behaviors, such as rocking or repeating words or phrases
have difficulty adapting to changes in routine
be sensitive to light, sound, clothing, or temperature
Some people on the spectrum may also demonstrate strengths for certain types of learning and remembering detailed information. They can be strong visual or auditory learners and may be gifted in math, science, music, or art.
Autism Spectrum Diagnosis
When a child is between 18 and 24 months old, their pediatrician will conduct autism-specific screening that assesses behavior and development. If there are concerns, the doctor will refer the child to a team of specialists for a neurological assessment as well as cognitive and language testing. Specialists may include developmental pediatricians, pediatric neurologists, child psychologists or psychiatrists, and speech-language pathologists. Doctors with training in autism apply strict criteria before making a final diagnosis.
While ASD is typically diagnosed by 24 months of age, older children and adults can also be diagnosed. ASD may go unrecognized for years, especially in children who have mild symptoms or have other disabilities. With older children, caregivers or teachers may raise concerns about their social, emotional, and academic development. Adults may report communication challenges that interfere with work or social situations, repetitive behaviors, sensory issues, or restricted interests.
There is no cure for autism, but research shows that early intervention can help lessen developmental challenges and help children on the spectrum develop important skills. Services are available through local early intervention systems for children up to age 3 and through local public school systems for children 3 years and older. There are a variety of therapies and behavioral interventions for people of any age that can help reduce symptoms that interfere with everyday function.
A child with ASD may be more likely to achieve independence, healthy routines, and robust relationships through a personalized combination of therapies tailored to their specific needs. These can include developmental, behavioral, educational, social-relational, and alternative treatments. Often a combination of speech and language therapy, occupational therapy, and physical therapy can help with social and cognitive development. In some cases, medication may help manage irritability, aggression, self-harming behaviors, or other conditions such as ADHD, anxiety, and depression.
Autism Research Efforts
Current research efforts are exploring the causes, diagnosis, early detection, prevention, and treatment of autism.
The Center for Disease Control’s Study to Explore Early Development (SEED) is a multi-year research study designed to help identify factors that may put children at risk for ASD and other developmental disabilities.
Orlena was driving with her young daughter in the car when she suffered a stroke because of a rare brain vessel disorder called Moyamoya. After two brain surgeries and six months unable to care for her daughter, Orlena began to reclaim her independence and became a Moyamoya advocate.
At 15 years old, Zoe has been navigating her Tourette syndrome diagnosis for eight years. “I had to figure out at a young age how my emotions affect my tics, from good to awful ways. It has been frustrating to figure out on my own and learn to deal with. This was the first moment in my life where my parents couldn’t fix something for me.”
Sasha was diagnosed with epilepsy after sustaining a soccer-related brain injury in high school. Since then, Sasha has worked to find both a treatment that controlled her seizures and a career that fulfilled her desire to care for others. “Life isn’t meant to be lived taking multiple medications and having seizures you can’t control.”
Before frontotemporal lobe dementia, sometimes called Pick’s disease, Ken Keene Sr. was a respected community member and a handyman who could fix anything. For his oldest son and namesake Ken Keene Jr., there was nothing his father couldn’t do: “To my family, he was just that super dad. Then all of a sudden he’s reaching out for help.”
It started with a twinge. After a simple surgery and some physical therapy, Morgan wasn’t getting better. It took two more surgeries before she was diagnosed with Complex Regional Pain Syndrome (CRPS) type II.
In 2018, Kelly was diagnosed with glioblastoma after an MRI confirmed that a golf-ball-sized tumor above her right ear was affecting the left side of her body. After surgery to remove the tumor, Kelly was able to get through her darkest days with a healthy dose of humor. Now she is an advocate for other patients living with strokes and brain tumors.
When her father was diagnosed with vascular dementia in 2005, Nancy quickly shifted into the role of his caregiver. Nancy and her sisters drew from their individual strengths to provide their father with medical assistance and emotional support until his passing in 2012. At that time, he was diagnosed again with Lewy body dementia. “No matter what your financial situation, there’s probably going to be help out there… Just don’t do it alone, because burning yourself out is not going to help anybody.”
Maureen worked as a high school English teacher until she started experiencing a confusing array of symptoms that affected her ability to work, along with her relationships with family and friends. After visiting numerous specialists for years, Maureen received a delayed diagnosis of Lewy body dementia. Now Maureen wants to raise awareness about what life is like with living with this disease. “I felt that I just wanted to offer something to this community that I hadn’t been able to find really.”
For the first 32 years of his life, Joey experienced seizures from epilepsy. For several years, Joey worked hard in his career as a pipe welder and in construction until his seizures started happening more frequently and intensely. Brain surgery became Joey’s only viable option for treatment. Doctors were unsure if Joey would be able to survive after finding more brain damage than expected, but he surprised everyone by thriving during his post-surgery recovery.
At age 40, Ben was perfectly healthy and active until he started noticing the early symptoms of a neurological condition that weakened his physical movements. After a 2-year search for his diagnosis of X-linked adrenoleukodystrophy, he began his journey as an advocate for others living with rare diseases. Last year, Ben joined the board of the American Brain Foundation to further his impact.
In 2002, while her young daughter battled a fatal diagnosis of pons glioma, Michele experienced a life-threatening brain hemorrhage when a brain malformation she likely had since birth ruptured. She experienced drastic changes in the way her brain functioned, especially in regard to memory and spatial awareness. Today, Michele is still learning to adjust. “When someone’s brain is not functioning correctly it impacts everything in their life. It impacts how they think, how they feel about themselves, it’s a very hopeless space to be in as a person.”
Matt is a husband, father, and professional photographer. Over the past 11 years, he has had surgeries and radiation to remove five benign brain tumors. Following the third surgery, he began to experience more struggles in his daily life. “I think the biggest loss is my relationship to my family. They saw me as the dad and strong. Now they can’t count on me as much. It’s important to support people with brain disease ‘cause it can happen to anybody.’”
When she was in her early 30’s, Mary Jo’s relationship with her parents was forever altered by brain disease. Her father suffered a subdural hematoma, was diagnosed with diabetic neuropathy, and experienced a stroke while her mother was diagnosed with Alzheimer’s and dementia. “They’re a responsibility that I have to take care of as they have taken care of me.”
Tom suffers from dystonia, a painful neurological movement disorder with no known cure. When he first started experiencing strange pains and cramps in his neck muscles, he saw chiropractors and physical therapists—but when this didn’t help, Tom started down a long and painful road to an eventual diagnosis. Before his diagnosis at 30 years old, Tom was an athlete and an entrepreneur, but as his symptoms worsened, even performing everyday tasks became a challenge. Before long, the pain became debilitating. Over time, Tom learned to accept his new limitations and focus on his physical and mental health.