Early Signs

What is autism?

According to the National Institute of Health, autism spectrum disorders are a range of complex neurodevelopment disorders, characterized by social impairments, communication difficulties, and restricted, repetitive, and stereotyped patterns of behavior.  Autistic disorder, sometimes called autism or classical autism, is the most severe form of autism spectrum disorders, while other conditions along the spectrum include a milder form known as Asperger syndrome, and childhood disintegrative disorder and pervasive developmental disorder not otherwise specified.  Although autism spectrum disorders vary significantly in character and severity, they occur in all ethnic and socioeconomic groups and affect every age group.  Experts estimate that 1 out of 88 children will have an autism spectrum disorder (Centers for Disease Control and Prevention: Morbidity and Mortality Weekly Report, March 30, 2012- link to read full report below).  Males are four times more likely to have an autism spectrum disorder than females.

Signs and Symptoms

Autism spectrum disorders begin before the age of 3 and last throughout a person's life, although often times symptoms may improve over time. Some children with autism spectrum disorder show hints of future problems within the first few months of life. In others, symptoms might not show up until 24 months or later. Some children with autism spectrum disorders seem to develop normally until around 18 to 24 months of age and then they stop gaining new skills, or they lose the skills they once had.

An individual may exhibit the following*:

  • Not respond to their name by 12 months
  • Not point at objects to show interest (point at an airplane flying over) by 14 months
  • Not play "pretend" games (pretend to "feed" a doll) by 18 months
  • Avoid eye contact and want to be alone
  • Have trouble understanding other people's feelings or talking about their own feelings
  • Have delayed speech and language skills
  • Repeat words or phrases over and over (echolalia)
  • Give unrelated answers to questions
  • Get upset by minor changes
  • Have obsessive interests
  • Flap their hands, rock their body, or spin in circles
  • Have unusual reactions to the way things sound, smell, taste, look, or feel

* According to CDC Developmental Early Signs


The Modified Checklist for Autism in Toddlers (M-CHAT) is a validated screening for toddlers between 16 and 30 months of age, to assess a risk for autism spectrum disorders. To access and complete the M-CHAT, please visit here.

The M-CHAT Follow-Up Interview™ is also available for download here: M-CHAT Follow-up Interview. The interview is designed to reduce the cases of children who fail the M-CHAT but do not have an autism spectrum disorder. It is highly recommended that M-CHAT users also incorporate the M-CHAT Follow-up Interview into the screening process, given that recent findings demonstrate that the interview greatly reduces the false positive rate, which avoids unnecessary referrals. For more information, please refer to the following references:

Kleinman et al. (2008) Journal of Autism and Developmental Disorders


For additional resources on signs and symptoms of autism:
  • Center for Disease Control
  • National Institute of Health


For comparison, below is a listing of typical developmental milestones by age.

Developmental Milestones by Age

By 3-4 months

  • Watches faces with interest and follows moving objects 
  • Recognizes familiar objects and people; smiles at the sound of your voice 
  • Begins to develop a social smile.
  • Turns head toward sounds

By 7 Months

  • Responds to other people's emotions 
  • Enjoys face-to-face play; can find partially hidden objects
  • Explores with hands and mouth; struggles for out of reach objects 
  • Responds to own name
  • Uses voice to express joy and displeasure; babbles chains of sounds

By 12 Months/1 Year

  • Enjoys imitating people; tries to imitate sounds 
  • Enjoys simple social games, such as “gonna get you!”
  • Explores objects; finds hidden objects
  • Responds to “no;” uses simple gestures, such as pointing to an object 
  • Babbles with changes in tone; may use single words (“dada,”“mama,” “Uh-oh!”)
  • Turns to person speaking when his/her name is called.

By 24 Months/2 Years

  • Imitates behavior of others; is excited about company of other children 
  • Understands several words
  • Finds deeply hidden objects; points to named pictures and objects 
  • Begins to sort by shapes and colors; begins simple make-believe play 
  • Recognizes names of familiar people and objects; follows simple instructions 
  • Combines two words to communicate with others, such as “more cookie?”

By 36 Months/3 Years

  • Expresses affection openly and has a wide range of emotions 
  • Makes mechanical toys work; plays make-believe 
  • Sorts objects by shape and color, matches objects to pictures 
  • Follows a 2- or 3-part command; uses simple phrases to communicate with others, such as “go outside, swing?”
  • Uses pronouns (I, you, me) and some plurals (cars, dogs)

It is important for doctors to screen all children for developmental delays. If your child’s doctor does not routinely check your child with this type of developmental screening test, ask that it be done.

In some cases, the primary care doctor might choose to refer the child and family to a specialist for further assessment and diagnosis. Specialists who can do this type of evaluation include:

  • Developmental Pediatricians
  • Child Neurologists
  • Child Psychologists or Psychiatrists

If the doctor sees any signs of a problem, a comprehensive diagnostic evaluation is needed.

To learn more about the relationship between childhood development and the role of synchronization of brain hemispheres, please read Dr. Mark Flannery’s article, “Milestones to maturity: An age-by-age breakdown for milestones and a look at risks for autism, ADD, anxiety, and other childhood disorders.


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