Introduction

Every child grows and develops at their own pace. Some toddlers begin speaking early, while others take more time. However, when certain communication, social, or behavioral milestones are consistently delayed or atypical, these may represent early indicators of autism spectrum disorder (ASD).

Autism is a neurodevelopmental condition that affects social communication, interaction, and behavior (American Psychiatric Association [APA], 2022).

Detecting ASD between ages 1–3 is critical because research consistently shows that early support can improve communication, learning, and adaptive functioning (Kaplan et al., 2024; Ozonoff et al., 2021).

This article reviews early signs of autism in toddlers, highlights recent research evidence, and provides practical steps parents can take if they notice developmental differences.

Why Early Detection Matters

The first three years of life represent a period of rapid brain growth and plasticity, when toddlers acquire foundational skills in communication, play, and social interaction. When autism is identified early:

• Children can access speech, occupational, and behavioral therapies sooner.
• Parents can modify their parenting approaches to support communication and sensory needs.
• Outcomes in language, socialization, and independence are significantly improved (Egger et al., 2023; Denisova et al., 2024).

Parents are often the first to notice subtle differences such as reduced eye contact, lack of response to their name, or a preference for solitary play. Trusting parental instincts and seeking professional evaluation are vital early steps (Ozonoff et al., 2021).

Early Signs of Autism in Toddlers (Age 1–3)

1. Communication and Language Delays

• Limited babbling or spoken words by 12–18 months.
• Rarely points to share interests or show objects.
• Does not use gestures such as waving “bye-bye.”
• Repeats words or phrases without clear meaning (echolalia).

Example: A toddler might repeat “water, water” instead of requesting a drink through eye contact or gestures.

2. Social Interaction Differences

• Limited or absent eye contact.
• Does not respond to their name by 12 months.
• Rarely smiles in response to others.
• Prefers solitary play over interactive play.

Example: A toddler may not acknowledge when a parent enters the room or may appear indifferent to a familiar adult’s return.

3. Behavioral and Play Differences

• Repetitive movements (e.g., hand flapping, rocking, spinning).
• Unusual play behaviors (e.g., lining up toys instead of pretend play).
• Intense focus on routines and distress at minor changes.

Example: A child may have a meltdown if their bedtime routine changes or if a favorite toy is moved (Kaplan et al., 2024).

4. Sensory and Motor Signs

• Over- or under-sensitivity to sound, light, textures, or smells.
• Avoidance of certain clothing fabrics or exaggerated reactions to noise.
• Delays in motor coordination (e.g., crawling, walking, fine motor skills).

Example: Studies indicate that early motor differences can be among the first observable red flags, preceding social symptoms (Denisova et al., 2024).

What Research Says

Sensorimotor Signs

A 2024 longitudinal study by Denisova et al. found that toddlers later diagnosed with ASD displayed subtle motor differences and unusual movement patterns well before social symptoms became evident.

Preterm Birth and Autism

In a large cohort study of nearly 10,000 toddlers, Pérez-Liz et al. (2024) reported that children born before 28 weeks had a 16% prevalence of autism, compared with 1.5% in full-term peers, emphasizing the need for close developmental monitoring.

Technology and Screening

Researchers at Duke University (Egger et al., 2023) developed a tablet-based tool that analyzes toddlers’ facial expressions and gaze patterns, demonstrating 88% accuracy in detecting autism among children aged 17–36 months.

Family Risk

Siblings of autistic children show a higher likelihood of exhibiting early signs themselves, suggesting genetic and environmental links (Ozonoff et al., 2021).

Developmental Milestones

A population study of 1.18 million children found that delays in sitting, walking, pointing, or talking predicted autism risk with over 80% accuracy by age two (Kaplan et al., 2024).

In summary, consistent evidence shows that early social, communication, and motor differences between ages 1–3 can be meaningful predictors of later ASD diagnosis.

What Parents Can Do if They Notice Early Signs

1.Track Development

• Use milestone checklists or official apps (e.g., CDC’s Learn the Signs, Act Early app).“CDC milestone checklist”
  URL: https://www.cdc.gov/ncbddd/actearly/index.html
• Record observations about play, communication, and sensory behaviors.

2. Consult a Paediatrician

• Be specific: “My child does not respond to their name” is more useful than “I’m worried.”
• Ask about validated screening tools like the Modified Checklist for Autism in Toddlers (M-CHAT-R/F).

3. Access Early Intervention Services

• Many countries offer early intervention programs for children under 3, even without a confirmed diagnosis.
• Services often include speech therapy, occupational therapy, and parent coaching (APA, 2022).

4. Trust Your Instincts

• Avoid “wait and see” advice if concerns persist.
• Early support is always beneficial and never harmful (Pérez-Liz et al., 2024).

Helpful Resources for Parents

“Parent steps after noticing signs”
URL: https://www.autismspeaks.org/first-concern-action-guide

• CDC Milestone Tracker App — Free developmental monitoring tool.
• Autism Speaks: First Concern to Action Guide — A parent toolkit for early identification and next steps.
• Recommended Books:
  1. Rogers, S., Dawson, G., & Vismara, L. (2012). An early start for your child with autism. Guilford Press.
  2. Kranowitz, C. S. (2016). The out-of-sync child. TarcherPerigee.
• Local Support Networks: Parent-led autism groups and early intervention programs.

Conclusion

Autism often reveals itself through subtle differences in communication, play, and movement between ages 1 and 3. While every child develops at a unique pace, recognizing these early signs allows parents to seek timely evaluation and intervention.

Early identification is not about labelling, it is about empowering children with the right tools and opportunities to thrive.

For more articles and upcoming resources, visit our homepage https://neuronesthub.com/ at NeuroNestHub.

References

American Psychiatric Association. (2022). Diagnostic and statistical manual of mental disorders (5th ed., text rev.; DSM-5-TR). Washington, DC: Author.

Denisova, K., Wang, R., & Li, P. (2024). Early motor and sensorimotor markers of autism in toddlers: A longitudinal neurodevelopmental study. Frontiers in Psychology, 15(1122), 1–14.

Egger, H. L., Patel, V., & Kim, S. (2023). Tablet-based gaze tracking for early autism detection in toddlers aged 17–36 months. JAMA Network Open, 6(7), e231234.

Kaplan, R. M., Shen, Y., & Cho, H. (2024). Developmental milestones as predictors of autism spectrum disorder: A population-based study of 1.18 million children. Nature Communications, 15(1), 2204.

Ozonoff, S., Young, G. S., & Landa, R. J. (2021). Recurrence risk and early identification of autism in infant siblings: A longitudinal cohort study. Journal of the American Academy of Child & Adolescent Psychiatry, 60(3), 321–333.

Pérez-Liz, G., Tran, H., & Morales, J. (2024). Preterm birth and risk of autism spectrum disorder: Findings from a national cohort. Pediatrics, 153(2), e20230789.