Autism spectrum disorder (ASD) is one of the most common neurodevelopmental disorders in children. According to recent figures, the prevalence rate is between 1% and 1.5% (Chiarotti & Venerosi, 2020). Nonetheless, many people still don’t have a good knowledge about this disorder which may lead to late diagnosis and contribute to parents’ frustration and child’s suffering. Early detection is key as early intervention facilitates the development of the child and helps them reach important milestones. In this article we will discuss early signs of Autism which may alert parents and help them decide whether they should seek professional help.

Autism spectrum disorder is a severe developmental disorder which expresses itself through a spectrum of symptoms (Zwaigenbaum, Brian & Angie, 2019). It is linked to differences in the brain that occur early in life (Zachor, 2012). The exact cause of the disorder remains a mystery to science, however positive family history and male sex were found to be strong risk factors (Zwaigenbaum et al., 2019). The main characteristics of ASD include: problems with communication, social interaction, presence of repetitive behaviors and restricted interests. These are often accompanied by sensory issues, such as oversensitivity or undersensitivity to sounds, smells or touch (Understanding autism, n.d.).

The signs and symptoms of Autism vary widely from person to person which makes it more difficult to diagnose. Research has also identified different patterns of onset of the disorder (Zwaigenbaum & Penner, 2018). While some children with ASD show symptoms within the first 12 months of life, in others symptoms may not be present until 24 months or even later (Hyman, Levy & Myers, 2020). A pattern that describes developmental regression (loss of previously acquired skills) has been identified in 32.1% of affected children (Barger et al., 2013). Additionally, Autism is not a physical disability. Therefore, people on the spectrum look no different to others. Although symptoms of ASD are neurologically based they manifest as differences in behavior. Autism is usually diagnosed in children about the age of 3 but the warning signs can be spotted much earlier (Understanding Autism Spectrum Disorder, n.d.).

How parents can spot the warning signs?

6–12 months. Clinical presentation:

  • Limited or no eye contact – not looking at caregivers when communicating or playing with
  • Reduced or limited smiles or other joyful expressions directed at people.
  • Limited reciprocal sharing of sounds or facial expressions.
  • No babbling – 12 month olds should look at someone while they babble and take turns
    (like a back-and-forth babbling “conversation”).
  • No gesturing (e.g., pointing, reaching, waving ‘bye-bye’, shaking their head as to say “no”).
  • Limited response to name when called – young children with ASD don’t respond when
    their name is called even though their hearing is fine. This is due to difficulties with
    paying attention and understanding language.

9–12 months. Clinical presentation:

  • Emerging repetitive behaviors (e.g., spinning or lining up objects, hand flapping) – these
    forms of behavior are also seen in normally developing children on occasion, but in babies
    with Autism they occur regularly.
  • Unusual play (e.g., intense visual or tactile exploration of toys).

12–18 months. Clinical presentation:

  • No single words.
  • Absence of compensatory gestures (such as pointing) – not looking in the direction of
    a caregiver’s finger when they point to something.
  • Lack of pretend play – only engaging with a small number of toys, or play with just a part of
    the toy (the wheels of the toy car) rather than the whole toy.
  • Limited joint attention (initiating, responding, sharing of interests).

15–24 months. Clinical presentation:

  • No spontaneous or meaningful two-word phrases.

Any age. Clinical presentation:

  • Parental and other caregiver concerns about the possibility of ASD.
  • Developmental regression (a loss of words, skills, or social connection) – this type of
    regression doesn’t happen with all autistic children. But approximately 20% to 50%
    of parents of children with ASD report that their child lost some skills during 2nd year.

Note. Adapted from “Early detection for autism spectrum disorder in young children” by L. Zwaigenbaum, J.A.Brian and A. IP, 2019, Paediatrics & child health, 24(7), p. 424-432. Copyright 2019 by Canadian Paediatric Society.


The early signs of ASD are easy to miss since they are manifested in lack of certain behaviors rather than in emergence of unusual ones. Thus, it is more difficult to spot them. For example avoiding eye contact, reduced vocalization, lack of social smiling and babbling by 12 months of age are all considered to be major predictors of later problem behavior (Thurm et al., 2018). As the child gets older the behavioral signs evolve and become more transparent. They include performing repetitive movements, engaging in unusual play, paying more attention to objects than people, delayed language skills and difficulties with biological functions (such as feeding or sleeping). It is important to mention that some of those behaviors also appear in healthy children, however they are only temporary. If the behavior persists for long period of time and occurs often, it is a sign of concern.

Due to different onsets and symptoms of ASD it is crucial to perform developmental screenings regularly. Diagnosis needs to be performed by a professional such as pediatrician, psychiatrist, psychologist or neurologist. If your child shows any of the early warning signs of Autism and you are concerned about the way they move, act, play or speak contact your pediatrician. You can also check the developmental milestone checklist provided on CDC Web site which helps to determine whether your child is developing accurately ( Careful observation can lead to early diagnosis, treatment and a favorable outcome. Studies indicate that the sooner a child receives intervention, the better their results will be (Lord & Bishop, 2010).

Joanna Kozłowska

Psicóloga, Equipo Psicoaula


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