Potentially early signs of autism spectrum disorder

Here are some of the most common early signs that may alert parents, caregivers, or professionals that a child could be on the autism spectrum:

• Lack of eye contact or limited use of facial expressions when interacting with others
• Not responding to their name by 12 months of age
• Delayed speech and language development or loss of previously acquired language skills
• Limited use of gestures, such as pointing, waving, or showing objects to others
• Rarely sharing enjoyment or interests with others (e.g., not showing or bringing things to share)
• Difficulty engaging in back-and-forth conversations or play
• Repetitive movements like hand-flapping, rocking, or spinning on the spot
• Lining up toys and objects instead of playing typically
• Focussing on part of an object rather than using the object as it was meant (e.g. spinning wheels of toy cars)
• Insistence on sameness, routines, or rituals, and becoming upset at small changes
• Highly focused interests or intense, unusual attachments to certain objects or topics
• Unusual reactions to sensory input, such as being overly sensitive to noises, lights, textures, or smells
• Walking on tip toes 
• Limited social smiling or lack of imitation of others’ behaviours
• Difficulty understanding or expressing emotions—their own or others’ (CDC, 2022; Autism Speaks, 2023).

These signs can appear as early as 12–18 months, though variations exist. Having one or two signs doesn’t necessarily mean a child has autism, but noticing several may warrant further evaluation.

DSM-5 criteria for autism spectrum disorder 

The Diagnostic and Statistical manual of Mental Disorders (DSM-V) defines three key areas for an Autism Spectrum Disorder (ASD) diagnosis:

• Social Communication and Interaction
  Children with ASD often have difficulty with social-emotional reciprocity, non-verbal communication (like eye contact or gestures), and developing or maintaining relationships.

• Restricted, Repetitive Behaviours or Interests
  This includes repetitive movements or speech, strict routines or rituals, intense interests, or unusual reactions to sensory input.

• Symptoms Present in Early Development
  Signs must be noticeable in early childhood, even if they become more apparent as social demands increase

• These disturbances are not better explained by global developmental delay or intellectual disability which frequently co-occur with ASD; to make dual diagnoses of ASD and intellectual disability, social communication should be below that expected for general developmental level.

Updated on:   09/02/2026 by: Dr. Jacques Duff – BA Psych; Grad Dip Psych; PhD; MAPS; MECNS; MAAAPB; MISNR; FANSA
Reviewed on: 22/02/2026 by: Bernard Ferriere - BA; Grad Dip App Psych; Dip Clinical Hypnosis; FCCP; MAPS; MASH; Clinical Psychologist