About Autism

• There are no biological markers for autism, so screening must focus on behavior.
• Studies comparing autistic and typically developing children show problems with eye contact, orienting to one’s name, joint attention, pretend play, imitation, nonverbal communication, and language development are measurable by 18 months of age.
• Current screening methods may not identify children with milder variants of autism, those without mental retardation or language delay

Symptoms of ASD typically become clearly evident during early childhood, between ages 12 and 24 months. However, symptoms may also appear earlier or later.

Early symptoms may include a marked delay in language or social development.

The DSM-5 divides symptoms of ASD into two categories:

• problems with communication and social interaction
• restricted or repetitive patterns of behavior or activities

To be diagnosed with autism, a person must experience symptoms in both of these categories.

ASD can involve a range of issues with communication, many of which appear before age 5.

Here’s a general timeline of what this might look like:

• From birth: trouble maintaining eye contact
• By 9 months: not responding to their name
• By 9 months: not displaying facial expressions reflective of their emotions (like surprise or anger)
• By 12 months: not engaging in basic interactive games, like peek-a-boo or pat-a-cake
• By 12 months: not using (or only using a few) hand gestures, like hand-waving
• By 15 months: not sharing their interests with others (by showing someone a favorite toy, for example)
• By 18 months: not pointing or looking where others point
• By 24 months: not noticing when others appear sad or hurt
• By 30 months: not engaging in “pretend play,” like caring for a baby doll or playing with figurines
• By 60 months of age: not playing turn-taking games, like duck-duck goose

Additionally, autistic children might have trouble expressing their feelings or understanding those of others starting at 36 months.

As they age, they might have difficulty talking or very limited speaking skills. Other autistic children might develop language skills at an uneven pace. If there’s a particular topic that’s very interesting to them, for example, they might develop a very strong vocabulary for talking about that one topic. But they might have difficulty communicating about other things.

As autistic children begin talking, they might also talk in an unusual tone that can range from high-pitched and “sing-songy” to robotic or flat.

They might also show signs of hyperlexia, which involves reading beyond what’s expected of their age. Children on the autism spectrum might learn to read earlier than their neurotypical peers, sometimes as early as age 2. But they tend to not comprehend what they’re reading.

While hyperlexia does not always accompany autism, research suggests nearly 84 percent of children with hyperlexia are on the spectrum.

As they interact with others, autistic children might have difficulty sharing their emotions and interests with others or find it hard to maintain back-and-forth conversation. Nonverbal communication, like maintaining eye contact or body language, might also remain difficult.

These challenges with communication can persist throughout adulthood.

In addition to the communication and social issues mentioned above, autism also includes symptoms related to body movements and behaviors.

These can include:

• Repetitive movements, like rocking, flapping their arms, spinning, or running back and forth
• Llining objects, like toys, up in strict order and getting upset when that order is disturbed
• Attachment to strict routines, like those around bedtime or getting to school
• Repeating words or phrases they hear someone say over and over again
• Getting upset over minor changes
• Focusing intently on parts of objects, like the wheel of a toy truck or the hair of a doll
• Unusual reactions to sensory input, like sounds, smells, and tastes
• Obsessive interests
• Exceptional abilities, like musical talent or memory capabilities

Some autistic people might experience additional symptoms, including:

• Delayed movement, language, or cognitive skills
• Seizures
• Gastrointestinal symptoms, like constipation or diarrhea
• Excessive worry or stress
• Unusual levels of fear (either higher or lower than expected)
• Hyperactive, inattentive, or impulsive behaviors
• Unexpected emotional reactions
• Unusual eating habits or preferences
• Unusual sleep patterns