Signs of Autism in Toddler and How to Spot Them Early

Signs of autism in toddler often appear as delayed speech, limited eye contact, little interest in social play, repetitive behaviors, or extreme sensitivity to sounds, touch, or routines. Spotting these early signs can help parents take action sooner, leading to better support and development for their child.

It’s also important to note that some signs of autism in infants can show up before the toddler stage, giving parents an even earlier chance to seek help.

Recognizing Autism Behaviors in Toddlers

Autism results in many observable behaviors that are stereotypical in nature, however it also results in a myriad of behaviors that are unobservable and have significant impact on the individual experiencing them. When beginning to identify signs of autism within a toddler, it is helpful to have a deeper understanding of how the behaviors can manifest and work alongside each other to form the specific presentation in the child.

Autism Spectrum Disorder (ASD)

ASD is a neurodevelopmental condition that impacts the domains of social communication and engagement in repetitive and restrictive behaviors. Autism is diagnosed in approximately 2% of people, with rates of diagnosis increasing significantly in the previous two decades.

Development in diagnostic tools and research into autism and its impact has allowed for earlier diagnosis to take place. The earlier a child is identified as being at risk of autism, the earlier they can access treatment and support for skill development, resulting in increased positive long-term outcomes. Identifying these signs and engaging in early intervention is crucial to better identify the specific needs for the child and develop individualized treatment plans accordingly.

5 Signs of Autism in Toddler

5 signs of autism in a toddler include communication challenges, social difficulties, repetitive behaviors, sensory sensitivities, and developmental milestone delays.

These 5 signs of autism in toddler are some of the most common early red flags – but there are also subtle behaviors parents often miss. Want to know what they are and how to support your child early? Keep reading.

1. Communication Challenges

Communication challenges are a core characteristic of autism spectrum disorder. The learning of communication begins at birth as children are exposed to both verbal and non-verbal communication regularly in their day-to-day lives. Children with autism can experience disruption in communication due to limitations in imitation and social skills, and other influences such as sensory sensitivities and limited attending skills. Children with autism may also experience difficulties in decoding language and understanding what is being said to them.

Limited or Lack of Speech

Limited or lack of speech is not a symptom of autism that is seen in every individual. Some individuals with autism have extended vocabularies and an impressive ability to communicate verbally. This is sometimes associated with high functioning autism, where a child may appear advanced in speech or certain skills but still shows other signs of autism.

That being said, one of the most common signs of autism in toddlers that leads to further investigation is this limited or lack of speech. Below are some examples of how autism impacts speech and language development.

• Uneven language development – children with autism may develop some speech and language skills and still not be at the same level of ability as their neurotypical peers. Their speech and language development is often non-linear and may lend itself to topics of high interest and be limited in other areas.
• Lack of interest in engaging in back and forth conversations with familiar people in familiar environments.
• Lack of responding to both vocal and non-vocal stimuli, signifying a disengagement from the social world.
• Communicate via gestures, leading, or reaching.
• Limitations in both expressive and receptive language.

Limited Non-Verbal communication :

Toddlers typically learn to communicate non-verbally within the first year of life. We often see infants using non-verbal communication such as eye gaze, vocalizations, and gestures. Non-verbal communication is an important way for humans to communicate their internal states to those not privy to internal information. Children with autism often have difficulties in reading the body language, facial expressions, and gestures of others, making it difficult to form and maintain relationships. 

• Limitations in using and reading gestures and body language is a common characteristic of social communication challenges for autistic individuals. Toddlers may avoid eye contact, show limited interest in the environment and people, and appear unaffected by changes in the environment as well as the emotions of others.
• Children with limited non-verbal communication may resort to communicating through behavior and emotional outbursts due to the frustration they feel at not being able to understand this form of communication.

Unusual Speech Patterns :

It is often seen that children with autism who have the ability to speak, will say things that are non-functional, seemingly have no meaning, and do not suit the context of the environment. Below are some examples of rigid or unusual speech patterns that may be apparent for a toddler with autism.

• Echolalia – repeating heard words in a non-contextual and non-functional way (for example, repeating a sentence multiple times in a conversation on a different topic).
• Scripting – repeating words, sentences, or phrases that have been heard and learned from their environment in a non-contextual and non-functional way.
• Poor listener response skills – for example, repeating the spoken question when the conversation partner is seeking an answer.
• Children with autism may not know how to alter speech patterns in terms of intonation, volume, and pitch.
• Vocal stereotypy – repeating sentences or singular words over and over again.

2. Social Difficulties

Social difficulties are also a core characteristic of autism. The symptoms of autism must impact upon a child’s ability to engage in social communication for a diagnosis of autism to be made. Poor social skills have the potential to lead to social isolation, bullying, and the development of co-occurring mental health issues for the child. Identifying the signs of autism in terms of social skills is crucial in finding support and strategies in teaching these skills while the child is still young.

As many toddlers are not at the point of socializing in a way that makes the signs of autism overtly observable, there are other ways in which it is possible to observe that the social skills of the child are impacted in some way. 

Lack of Interest in Social Interactions :

Having a toddler that seems to have a lack of interest in social interactions can be very distressing for a parent. A toddler with autism may engage in some of the following behaviors:

• Reduced eye contact
• Preferring to play alone
• Preferring to play with the same toys over and over again
• Limited interest in the environment
• Limited interest in peers
• A toddler with autism may appear disengaged when being spoken to, even by familiar people such as Mom and Dad.

Intervention for the development of social skills in an autistic toddler may focus on increasing attending skills, a foundational skill that is a prerequisite for the development of the more complex skills involved in social engagement.

Difficulties in Understanding or Interpreting Social Cues :

In any social situation, there are multiple cues that need to be picked up on and interpreted for a successful interaction. Interpreting social cues can be challenging for anyone, but a persistent impact in this domain is common for people on the autism spectrum. Social clues can include, but are not limited to:

• Facial expressions
• Gestures
• Body language
• Tone of voice
• Eye contact
• Others’ emotions

A toddler with limited interest in peers and their environment may find it increasingly difficult to take notice of, recognize and interpret the social nuances of the world. Being unable to communicate in social situations is detrimental to the development and maintenance of social relationships, a key factor in improving quality of life for children with autism moving through adolescence and into adulthood.

Limited or Absent Pretend Play :

The impacts of autism on social interactions and communication has the potential to severely influence the way an individual plays. Social interactions provide multiple opportunities for children to engage in a variety of play types, all of which teach social skills, imitation skills, practice of skills, and learning about the world. 

Pretend play is also known as imaginative, symbolic, or dramatic play. This type of play requires children to use their imagination to immerse themselves into imagined scenarios, play certain roles, and mimic real-life activities. Research shows that pretend play is a cornerstone of cognitive development and encourages children to think abstractly and engage in ad hoc problem solving skills. It is also a great opportunity for communication development and emotional awareness.

Children with autism can struggle to engage in varied play. Pretend play poses a particular challenge for autistic children as it is a very abstract concept for a child who finds it difficult to communicate and read social cues. Children with autism may exhibit the following signs surrounding pretend or imaginative play:

• Preferring to play with the same toy each time
• Repeating the sequence of play over and over again
• Manipulating objects in the same way each time they play
• Lining up toys repetitively 

It is important to note that children with autism often do engage in pretend play, but that it may just not look the same as a neurotypical peer of the same age. Individuals with autism may engage with the same objects and toys, but use them differently or focus on different parts of the object, rather than engaging in roleplay and imagined scenarios. The play skills of an autistic child may also be impacted by sensory sensitivities and a lack of confidence due to their comfort levels in social situations.

3. Repetitive Behaviors

Repetitive and restrictive behaviors are a core diagnostic criterion for autism. There are many types of repetitive behaviors that relate to autism, often classified into the categories of ‘lower-order’ and ‘higher-order’ behaviors. Lower-order behaviors refer to motor repetition, self-stimulation ( autism stimming), and repetitive movements with objects. Higher-order behaviors refer to the need for rituals, routines, as well as the occurrence of restricted interests.

Repetitive Movements (Stereotypy) :

Stereotypy has the potential to cause injury to an individual and have a significant impact on learning and the daily life for themselves and their family. Stereotypy can be difficult to attribute to autism, as the movements are common for children during early childhood, often disappearing between the ages of 4 and 6. Some common repetitive motor movements seen in toddlers are:

• Spinning
• Rocking back and forth
• Hand-flapping
• Head-banging
• Repeating phrases
• Face and mouth stretching
• Banging toys together
• Repeating cause and effect motions

Avoid intervening with stereotypic behaviors if the individual uses them functionally to regulate their nervous system. Generally, intervention should only occur if the behavior is becoming a significant barrier to learning or causing physical injury to the child.

It’s important to remember that repetitive behaviors in a child do not necessarily indicate autism and may also be related to other conditions like Rett syndrome, ADHD, OCD, or schizophrenia.

Insistence on Sameness and Routines :

Children with autism may experience an intrinsic need for routine and sameness in order to function throughout their day. Autistic individuals thrive on predictability and knowledge, making change daunting and scary. Being inflexible to change is generally a coping mechanism in finding understanding of a situation and being able to make sense of an unpredictable and often scary world. In a toddler, this sign of autism may manifest in one or more of the following ways:

• The need to complete a routine in the same way each time
• Engaging in rituals 
• Emotional escalation with the perception of upcoming change
• The need to follow rules

This rigidity has the potential to impact upon the social skill of the child as social interactions can be particularly unpredictable. Children with autism may attempt to control play and social situations in order to make the play evolve to their expectations. The impact can also affect parents and families, requiring them to perform tasks in a routine manner each day.

Special Interests :

Special or ‘intense’ interests are a common characteristic of autism in children. That said, neurotypical children, particularly boys, commonly exhibit these behaviors up until the age of two. The difference between the two individuals is often the level of intensity and duration of the special interest, as well as the abundance of information that an autistic individual often seeks out about the topic and subsequently disseminates to those around them.

Intense interests can consume a child’s attention and, when they impair social relationships or disrupt family routines, qualify as a repetitive behavior associated with autism. Children with autism often speak about their topic of interest in one-sided conversations, limiting their participation in back and forth conversations, a crucial social skill for development.

Special interests often give the individual a sense of pride and enhancement of self-esteem. Having an abundance of information about a preferred topic can often work as a form of self-regulation and comfort while providing a form of distraction during stressful times. Working with a child with specific special interests is helpful to clinicians and therapists, as it gives them the opportunity to incorporate these interests into their teaching. When therapists motivate children to engage in activities, they are more likely to experience behavior change and learning.

4. Sensory Sensitivities

Sensory sensitivities are a hallmark characteristic of autism. Not all people with sensory issues are on the spectrum, and not all autistic people have sensory sensitivities. Approximately 96% of children with autism encounter barriers due to hyper (over) or hypo (under) sensitivity to sensory stimuli.

Those with sensory sensitivities may find processing auditory, olfactory, tactile, visual, and taste sensations in the same manner as a typically developing child. Sensory overload can trigger internal panic in individuals, pushing them into a fight-or-flight response where they often use behavioral escalations for regulation.

People often misunderstand behavior resulting from a sensory processing issue as ‘naughty’ or ‘unnecessary. It is important for those working with the child to be able to identify when sensory experiences are becoming overwhelming in order to provide them with an escape from the stimuli or strategies for engagement with it. Sensory sensitivities can result in some of the following behaviors for toddlers:

• Avoidance of specific environments
• Inability to focus on learning or tasks at hand
• Emotional escalation with unobservable triggers
• Limited food range
• Stimming (rocking, spinning, flapping hands etc.)

Hypersensitivity and Hyposensitivity :

Hypersensitivity refers to a person who may find it difficult to understand where their body is in relation to other things in their environment. Being hypersensitive to sensory input may avoid sensory input as it makes them feel uncomfortable. Children with hypersensitivity are eternally on edge or hypervigilant, significantly impacting their behavioral responses.

Hyposensitivity refers to when a person is ‘under-sensitive’ to sensory input, leading them to seek sensory experiences that are intense and require a lot of body movement. Hyposensitivity makes children less responsive to many sensations, a challenging symptom when it comes to pain and injury.

 ➡ Hypersensitivity Examples

• Disliking the feeling of water on the head, making it difficult to wash hair and engage in proper hygiene practices.
• Misapplication of force – using excessive force where unnecessary due to being unable to sense how much force they are using.
• Needing to block ears when an auditory stimulus is present in the environment.
• Being unable to focus in educational settings due to too many sensory inputs occurring at once.
• Becoming distressed when too many people are talking or too much is going on.

 ➡ Hyposensitivities Examples

• Craving fast and intense movements.
• Enjoying jumping, running, spinning, and heightened physical activity.
• Not reacting to loud noises in the environment.
• Seeking out sensory inputs such as deep pressure, loud music etc.
• Accidental injuries.
• Minimal reaction to pain.
• Inability to recognize the physiological reactions of their body to things like hunger, going to the toilet, or being full.

How to Help Children Cope with Hyper- and Hypo-Sensitivity to Sensory Stimuli ?

Here are some strategies to help children cope with hyper- and hypo-sensitivity to sensory stimuli:

Hypersensitivity

• Manipulate the environment to be calm and free of intense sensory stimuli.
• Turn off or dim lighting.
• Restrict noise or reduce noise levels.
• Reduce addition of new scents in the environment.
• Listen to the child in regards to fabrics and clothing.
• Incorporate ‘safe foods’ among new foods to try.

Hyposensitivity

• Provide stimulating toys and activities.
• Provide deep pressure and sensory input during times of dysregulation.
• Allow freedom to engage in high intensity body movements.
• Use resources such as watches to provide time intervals for body checking and engaging in response behaviors (such as going to the toilet).

5. Developmental Milestone Delays

It is within the first two years of life that parents begin to realize that their child may be experiencing challenges that could be related to autism. Extensive research explores how delays in developmental milestones might link to earlier autism diagnoses. Studies show that individuals on the autism spectrum may experience delays in reaching cognitive, social, communication, emotional, and physical milestones compared to their peers.

It is important to note that not all autistic children experience developmental milestone delays and that many, if not most, do reach some of the milestones on time or even earlier than expected.

Some toddlers with autism may experience regression in previously acquired skills, such as language or social abilities. This can be worrying for parents, and often raises the question, “does autism get worse with age?“

It is possible that autism is having an impact if a child is experiencing one or more of the following delays by the age of 3:

• Not responding to their name
• Limited show of facial expressions
• Does not engage in pretend play
• Has limited interest in the environment and peers
• Cannot determine when others are upset or hurt
• Previously acquired skills begin to regress
• Lacks eye contact
• Does not engage in social sensory routines such as songs and rhymes

Regression in Previously Acquired Skills :

Regression in children with autism is not uncommon, in fact between 8% and 47% of children will experience some form of regression in previously acquired skills. The most common regression is language skills, however other areas include social skills and behavior.

The 3 Levels of Autism in Toddlers

Autism in toddlers is classified into three levels, showing how much support a child may need. Recognizing the level early helps parents and caregivers provide the right guidance and interventions.

Level 1 Autism in Toddlers – Mild Support Needed

• Slight difficulty with social communication
  
• Struggles with transitions or new routines
  
• Can play independently but may need prompts to join others
  

Level 2 Autism in Toddlers – Moderate Support Needed

• Noticeable challenges with back-and-forth interaction
  
• Limited eye contact or social gestures
  
• Needs help coping with changes in environment or routines
  

Level 3 Autism in Toddlers – Substantial Support Needed

• Very limited communication and social interaction
  
• Difficulty coping with everyday tasks without help
  
• Requires intensive support for learning, play, and engagement
  

Early Intervention Matters :

The earlier a toddler receives support tailored to their level, the better they can develop social, communication, and daily living skills. Therapies, structured routines, and guidance from a multidisciplinary team help toddlers reach their full potential and improve long-term outcomes.

Early Intervention: The Key to Supporting Autism in Toddlers

Early intervention refers to the specialized support provided when a child at risk for autism engages in therapeutic services as soon as possible. This support targets the development of skills typically acquired in the first two years of life.

During early intervention, a child usually interacts with a multidisciplinary team of clinicians and specialists to identify areas for development and skill acquisition. These teams may include various professionals, such as physicians, psychologists, psychiatrists, behavior therapists, occupational therapists, and speech and language pathologists.

The multidisciplinary team will collaborate to form a comprehensive treatment plan that is developed based upon assessment of the individual needs of the child, their strengths, their interests, and any external factors influencing the presentation of the autism symptoms.

Choosing therapies that are going to benefit a child is a daunting task for parents and caregivers, but through early interventions, parents will access a variety of services that will provide education and support in the management of the child’s symptoms.

Conclusion

Recognizing the signs of autism in toddlers is essential in seeking early intervention and support. As discussed in this article, autism has the potential to impact various aspects of a child’s development including communication, social skills, sensory sensitivities, repetitive behaviors, and the reaching of developmental milestones.

Identifying the signs of autism early and engaging with healthcare professionals will significantly improve outcomes for the child and lead to the development of skills that will assist them in reaching their full potential. Parents are in a unique position to observe, learn, and understand the experience of their autistic child and address their needs in a way that will promote growth, learning, and overall well-being.