Autism Symptoms & Signs: A Complete Guide for Parents
Understanding autism spectrum disorder (ASD) symptoms can help parents recognize early signs and seek appropriate support. This comprehensive guide covers symptoms across all ages, from infancy through school age.
Key Facts About Autism Symptoms
- Autism affects approximately 1 in 36 children in the United States according to the CDC
- Early signs can appear as young as 6-12 months
- Boys are 4 times more likely to be diagnosed than girls
- Early intervention significantly improves outcomes
Expert Insight: Recognizing the Signs Early
"With over 20 years of experience in ABA therapy, I've worked with hundreds of families who initially weren't sure whether the behaviors they noticed were cause for concern. Trust your instincts as a parent. If something feels different about your child's development, seeking an evaluation is never the wrong choice – even if everything turns out to be typical development, you'll have peace of mind."
– Jennifer Harbour, M.S., BCBA, Clinical Director at Buzz ABA
Specializing in verbal behavior and early childhood development
Autism Symptoms by Age
Autism symptoms can vary significantly depending on age. Here's what to look for at different developmental stages:
6-12 Months
- •Limited or no eye contact
- •Doesn't respond to name by 9 months
- •Doesn't smile back when you smile
- •Limited facial expressions
- •Doesn't reach to be picked up
- •Doesn't follow objects with eyes
12-18 Months
- •No single words by 16 months
- •Doesn't point to show interest
- •Loss of previously acquired skills
- •Limited imitation of others
- •Doesn't wave goodbye
- •Prefers to play alone
18-24 Months
- •No two-word phrases by 24 months
- •Doesn't engage in pretend play
- •Lines up toys or objects
- •Gets upset by minor changes
- •Unusual reactions to sounds or textures
- •Repetitive movements (rocking, spinning)
2-3 Years
- •Difficulty with back-and-forth conversation
- •Unusual tone of voice
- •Repeats words or phrases (echolalia)
- •Intense interest in specific topics
- •Difficulty understanding feelings
- •Prefers routines and resists change
4-5 Years
- •Difficulty making friends
- •Trouble understanding social cues
- •Takes things literally
- •Difficulty with imaginative play
- •Strong reactions to sensory input
- •Difficulty with transitions
School Age
- •Struggles with group activities
- •Difficulty reading social situations
- •Intense focus on specific interests
- •Challenges with flexibility
- •May experience bullying
- •Anxiety in social situations
Core Autism Symptoms Explained
According to the American Psychiatric Association's DSM-5, autism spectrum disorder is characterized by two main categories of symptoms: social communication challenges and restricted/repetitive behaviors.
Social Communication
Challenges with verbal and nonverbal communication in social contexts
Social Interaction
Difficulties developing and maintaining relationships
Restricted Interests
Highly focused interests that may be unusual in intensity or focus
Repetitive Behaviors
Repetitive movements, speech, or use of objects
Sensory Differences
Unusual responses to sensory input
When to Seek Professional Help
The American Academy of Pediatrics recommends autism screening for all children at 18 and 24 months. However, you should contact your pediatrician if you notice:
- No babbling by 12 months
- No pointing or waving by 12 months
- No single words by 16 months
- No two-word phrases by 24 months
- Any loss of language or social skills at any age
Free Autism Screening Tools
Take our free, validated screening tools to help identify potential signs of autism:
M-CHAT-R Screener
For toddlers ages 16-30 months. A 20-question screening tool recommended by pediatricians.
Take M-CHAT ScreeningCAST Screener
For children ages 4-11 years. A comprehensive 37-question assessment tool.
Take CAST ScreeningFrequently Asked Questions
Related Resources
Autism Diagnosis Guide
Complete guide to the evaluation process.
Autism in Girls
Why signs are often missed in girls and women.
Autism Levels Explained
Understanding Level 1, 2, and 3 support needs.
Understanding Autism Regression
When children lose previously acquired skills.
Late Autism Diagnosis
Finding support after diagnosis at any age.
Early Intervention Benefits
Why starting therapy early makes a difference.
Start Your Child's Journey Today
Buzz ABA provides comprehensive, evidence-based ABA therapy in Concord, Manchester, Nashua, and surrounding NH communities. Our neurodiversity-affirming approach helps children thrive.
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