Signs and Symptoms

If autism is caught in infancy, treatment can take full advantage of the young brain’s remarkable plasticity. Although autism is hard to diagnose before 24 months, symptoms often surface between 12 and 18 months. If signs are detected by 18 months of age, intensive treatment may help to rewire the brain and reverse the symptoms.

The earliest signs of autism involve the absence of normal behaviors—not the presence of abnormal ones—so they can be tough to spot. In some cases, the earliest symptoms of autism are even misinterpreted as signs of a “good baby,” since the infant may seem quiet, independent, and undemanding. However, you can catch warning signs early if you know what to look for. Some autistic infants don’t respond to cuddling, reach out to be picked up, or look at their mothers when being fed.

Early signs Your baby or toddler doesn’t

• Make eye contact, such as looking at you when being fed or smiling when being smiled at 

• Respond to his or her name, or to the sound of a familiar voice 

• Follow objects visually or follow your gesture when you point things out 

• Point or wave goodbye, or use other gestures to communicate 

• Make noises to get your attention 

• Initiate or respond to cuddling or reach out to be picked up 

• Imitate your movements and facial expressions 

• Play with other people or share interest and enjoyment

• Notice or care if you hurt yourself or experience discomfort

Developmental Redflags

The following delays warrant an immediate evaluation by your child’s paediatrician: 

By 6 months: No big smiles or other warm, joyful expressions 

By 9 months: No back-and-forth sharing of sounds, smiles, or other facial expressions 

By 12 months: Lack of response to name, No babbling or “baby talk” , No back-and-forth gestures, such as pointing, showing, reaching, or waving

By 16 months: No spoken words 

By 24 months: No meaningful two-word phrases that don’t involve imitating or repeatin