Signs and Symptoms of Autism Spectrum Disorder: What You Need to Know

Until three of my children were diagnosed with autism, I had very little understanding of what it actually looked like. Like so many parents, I had heard of autism, but I didn’t know the real signs and symptoms of autism, especially in toddlers and young children.

I truly believe that education is the key to awareness and acceptance. This guide is here to help you recognize the signs and symptoms of autism so you can feel more confident in what to look for and when to seek support.

📌 Editor’s Note: This post was originally published in 2017 and updated in 2025 to reflect current language, understanding, and best practices around autism.

What is Autism Spectrum Disorder (ASD)?

Autism is a neurodevelopmental condition that affects how a person communicates, processes information, and experiences the world.
It is typically identified in early childhood, though many are diagnosed later in life. Autism exists on a spectrum, which means signs and support needs vary widely from person to person.

Because autism is a spectrum, no two autistic individuals are exactly alike. That said, most people diagnosed with autism experience differences in three key areas:

Communication (Verbal & Non-Verbal)

Communication can look very different from child to child. Some may speak fluently, while others might use few words or none at all. Others might rely on scripts, gestures, or communication devices. Eye contact, tone of voice, or body language might not match what’s typically expected—but that doesn’t mean they aren’t communicating. We just have to learn how to listen differently.

Social Interaction & Relationships

This is an area where a lot of misunderstanding happens. Autistic kids might prefer playing alone, take time to warm up socially, or struggle with picking up on social cues. That doesn’t mean they don’t care or don’t want friends—it just means they connect differently. Many autistic people form incredibly deep, meaningful relationships once you give them the space to be themselves.

Flexibility in Thinking & Behavior

Routines and predictability are often really important. Changes can feel overwhelming, and that’s okay. Autistic individuals might also have focused interests that they’re really passionate about—sometimes called “special interests.” These aren’t just hobbies; they’re often sources of joy, comfort, and expertise. Repetitive behaviors like hand-flapping or pacing aren’t bad habits—they’re often a way to self-soothe and regulate emotions.

Understanding these core areas helps shift the conversation away from “what’s wrong” and toward “what’s different.” And different isn’t less—it’s just different.

Early Signs and Symptoms of Autism in Infants and Toddlers

Disclaimer: Not all autistic children will show every sign listed here, and some may show signs at different developmental stages. Every child is unique.

• No big smiles or other warm, joyful expressions by 6 months
• No back-and-forth sharing of sounds, smiles, or other facial expressions by 9 months
• Does not answer to name by 12 months
• There is no babbling or “baby talk” by 12 months
• No pointing, reaching or waving by 12 months
• Has no spoken words by 16 months
• No meaningful two-word phrases (non-repeating) by 24 months
• ANY REGRESSION OR LOSS OF SPEECH

These early signs and symptoms of autism may show up in the first year or two of life, though some children may develop typically before regressing later.

Common Signs and Symptoms of Autism in Children

While every autistic child is unique, many parents notice a consistent pattern of behaviors that match the signs and symptoms of autism. Recognizing these early can lead to earlier support.

• Extremely Intense Emotions
• Speech delay and, or learning disability
• May not want to be held/touched/cuddled
• Avoidance & sensitivity to noise and sound
• Meltdowns and difficulty self-regulating
• Twirling and spinning of self and objects
• Social & emotional Immaturity
• Different ways of expressing empathy or emotional understanding
• Difficulties falling and staying asleep
• Anxiety / Depression
• Motor coordination challenges or sensory-motor differences
• Low muscle tone, tires easily during physical activity
• Problems Playing with Others, Appearing “Bossy” or “Controlling”
• May relate to peers differently or prefer adults
• Inflexible Emotions and behaviors Can’t Let Go of Issues
• May struggle with traditional social norms or find friendships in different ways
• Inconsistent Eye Contact with others
• Extreme intensity of interests
• Lack of Coping Skills struggling with unexpected transitions
• Struggles with conversations, very one-sided
• Monotone or varying vocal inflections, often related to communication style
• Persistent repetition of words or actions
• Impulsive, lack of impulse control

Signs & Symptoms of Autism Spectrum Disorder

If you recognize signs of autism in your child, don’t hesitate to speak with your pediatrician or a developmental specialist. While early support can be beneficial, many children and adults thrive once they have the right tools, understanding, and community.

Whether you’re just starting to research or already suspect something, learning about the signs and symptoms of autism is one of the most empowering things you can do as a parent.