Speech Delay vs Autism: Understanding the Key Distinctions

speech delay vs autism

When a child isn’t talking, concerns can arise about the potential correlation between a speech delay and autism. 

Delayed language skills are characteristic of children with autism. However, a speech delay does not always indicate the presence of Autism Spectrum Disorder. 

The two hallmark characteristics of Autism Spectrum Disorder (ASD) are: 

  • Social communication deficits
  • Restrictive repetitive behaviors (RRBs) 

In contrast, a child with a speech delay can show challenges with communication without demonstrating those characteristics. 

Differentiating a speech delay vs autism is an important step in helping a child improve their communication skills. Here we’ll delve into the distinctions between the two disorders to help parents and caregivers navigate concerns by understanding whether their child has solely a speech delay or autism.

The Difference between Speech and Language Delays

A speech delay involves difficulties producing speech sounds, while a language delay includes challenges in understanding and using words and sentences to communicate. 

Although the terms are sometimes used interchangeably, it is important to differentiate between a speech delay and a language delay. Knowing which one applies to a child can help caregivers understand the types of communication difficulties the child has and how to help. 

Speech Delay: Definition, Signs, Causes

A speech delay occurs when a child does not say sounds by the expected ages according to developmental milestones. 

Speech delay is a broad term and is often used interchangeably with the term language delay, also known as late language emergence (LLE). This refers to a delay in the onset of language (the use of or understanding of words) without another diagnosed disability or developmental delay in motor or cognitive domains.   

A child with a language delay can show difficulties with expressive communication only (expressive language delay), or those who show delays in both using and comprehending language (mixed expressive and receptive language delay). 

Signs of a Speech Delay 

If a child has not met the milestones listed here by the age range outlined, it could be an indication of a speech delay.  

It should be noted that this list is intended to be used as a guide to inform families and professionals of the expected developmental milestones. If there are concerns, the child should be seen by a professional (such as a licensed Speech-Language Pathologist) for a thorough evaluation:

  • By 3 Months
    • Makes cooing sounds
  • By 5 Months
    • Laughs, makes playful sounds
  • By 6 Months
    • Babbles sounds with early developing consonants, like ba or puh
  • By 1 Year
    • Babbles longer strings of sounds (ex: bababa)
  • By 3 Years
    • Produces early developing consonant sounds: m, n, h, w, p, b, t, k, g, and f within words
  • By 4 Years
    • Others can understand at least 50% of the child’s speech (50% intelligible to others) 
    • Produces the y and v sound in words
    • May still have trouble producing later developing consonant sounds such as: s, sh, ch, j, ng, th, z, l, and r

Signs of a Language Delay 

If a child is not demonstrating these skills within the expected age range, that is indicative of a language delay.

This list is intended to be used as a guide to inform families and professionals of the expected developmental milestones. With concerns, the child should be seen by a professional (such as a licensed Speech-Language Pathologist) for a thorough evaluation:

  • By 12 Months:
    • Babbles strings of sounds (ex: mamama)
    • Points and waves 
    • Imitates sounds
    • Says 1 to 2 words (ex: dada)
  • By 18 Months:
    • Follows simple, 1-step directions
    • Shakes head for “yes” and “no”
    • Understands the names of common objects and body parts
    • Uses a combination of babbling or jargon with real words 
  • By 24 Months: 
    • Uses words to ask for help 
    • Combines 2 words to form phrases
    • Uses and understands at least 50 different words
  • 2 to 3 Years: 
    • Says their name 
    • Asks “why” and “how” questions
    • Answers “what” questions 
    • Uses 2 to 3 word phrases
  • 3 to 4 Years:
    • Tells a story from a book or video
    • Uses location words like “inside” and “under” 
    • Recognizes signs and logos 

Causes of a Speech Delay 

A child may have delayed speech due to certain diagnoses, such as:   

  • Dysarthria (weakness of the oral muscles used for producing speech) 
  • Traumatic Brain Injury (TBI) 
  • Developmental DIsorder (such as autism) 
  • Genetic Syndrome (ex: Down syndrome) 
  • Hearing Loss
  • Neurological conditions (ex: Cerebral Palsy) 

In many cases, the cause of a speech delay is unknown and the child’s speech production skills can improve over time with Speech Therapy. 

Diagnosis of a Speech Delay

For an accurate diagnosis and ongoing progress monitoring, it’s essential to consult a Speech-Language Pathologist (SLP). The SLP can complete a thorough assessment, provide an accurate diagnosis, and develop a treatment plan designed to address the client’s specific deficit areas and improve their skills. 

Autism Spectrum Disorder: Definition, Signs, Causes

Autism Spectrum Disorder (ASD) is defined by the American Psychiatric Association as a neurological and developmental disorder that involves difficulties with social communication, restricted interests, and repetitive behavior. 

Signs of Autism 

The core signs of ASD are: 

  • Social communication deficits
    • Trouble interacting with others by using verbal and/or nonverbal communication appropriately. 
  • Difficulties understanding how others are communicating verbally or nonverbally
    • Challenges interpreting body language
    • Difficulty interpreting sarcasm and abstract or figurative language
    • Deficits in comprehending language 
    • Trouble taking another person’s point of view (Theory of Mind) 
  • Difficulties using nonverbal or verbal communication with others
    • Trouble making friends
    • Difficulty playing games with others (social games, such as peak-a-boo)
    • Challenges in initiating or sustaining conversation 
    • Decreased use of eye contact, body proximity, or appropriate gestures (such as waving or pointing) to communicate
    • Decreased interaction with others/preference for playing alone 
  • Restrictive and repetitive behaviors (RRBs) or interests  
    • Specific behaviors that the individual displays repetitively. 
  • Include behaviors such as:
    • Lining up toys
    • Atypical play behaviors (spinning objects repetitively instead of playing with them)
    • Hand flapping, rocking
    • Echolalia (immediate – repeating what others say, and delayed – scripting lines previously heard from others or in videos or books) 
  • Focused interests
    • For example, limits play to a certain type of toy
    • Perseverates on a certain topic during conversation (ex: a favorite video game) 
    • Focused on parts of objects (such as the wheels on a car versus pushing the toy car itself) 
    • May have difficulty transitioning from preferred interests and become upset

Many individuals with autism also show other related characteristics, such as the following: 

  • Delayed language skills 
  • Delayed speech production skills 
  • Cognitive delays 
  • Hyperactivity 
  • Feeding difficulties 
  • Sleeping difficulties 
  • Behavior difficulties (anxiety, difficulty handling emotions) 

Autism is considered a spectrum, and a child may demonstrate a range of symptoms (from a few to several). Symptoms can also range in their level of severity. 

Causes of Autism 

The exact causes of autism are not fully understood, and more research is needed in this area. It is generally accepted that there are several potential causes. These include:

  • Genetic Factors
    • Certain gene mutations or variations are associated with autism 
    • More than 100 genes mutations have been identified as presenting a substantial risk for autism 
  • Environmental Causes
    • Profound social isolation
    • Toxins, such as viral and bacterial pathogens, and prescribed medications
    • Research is investigating potential influences of toxins such as cigarette smoke, heavy metals, and pesticides. 
  • Maternal Factors
    • Parental age
    • Pregnancy related factors (maternal obesity, gestational diabetes, and use of certain medications during pregnancy)
    • Maternal antibodies/Autoimmune diseases 
  • Birth Complications
    • Asphyxia-related complications during birth
    • Prematurity 
  • Biological Differences
    • Neurological differences (difficulties with brain connections or growth in specific areas of the brain)
    • Metabolic problems (differences in the body’s metabolism/energy production system) 
    • Problems with the immune system 

Diagnosis of Autism 

Early identification of autism typically leads to early intervention, which results in improved outcomes in therapy. If parents have concerns that their child is showing signs of autism, they should have the child evaluated by a professional who can provide an accurate diagnosis. 

Professionals who can diagnose autism include:

  • Psychologist/Neuropsychologist
  • Psychiatrist 
  • Developmental Pediatrician
  • Neurologist

The child may also be referred to other specialists, such as a Speech Therapist, who can assess and diagnose related challenges that the child may be experiencing. This includes speech and language disorders, and others.  

Speech Delay or Autism?

Is a speech delay a sign of Autism? It can be. Delayed speech is often one of the first symptoms that children with Autism may show. 

While speech delays can be a symptom of autism, not all children with speech delays have autism. How do you know if a child has only a speech delay or is showing signs of autism? A close look at these key differences between autism and speech delay can help. 

  • Social communication difficulties. Children with autism may prefer to play alone, and have difficulty understanding and using words or nonverbal communication to interact with others. Children with autism may show these signs (which would be absent in those with only a speech delay): 
    • Reduced eye contact
    • Preference for playing alone
    • Reduced initiation of communication (ex: a child may not bring an adult a toy to ask for it, or use words to request “help”) 
  • Restrictive repetitive behaviors. Highly focused interests and repetitive behaviors are core characteristics specific to autism. They are not typically seen in children who have a speech delay alone.
    • Children with speech delays: play with toys in the intended way (ex: putting pieces in a puzzle) 
    • Children with autism: may line up puzzle pieces and become upset if they are moved. 
  • Sound production difficulties as a primary deficit. Children with speech delays attempt to communicate with others but may have difficulty pronouncing certain sounds correctly. In autism, the child may not consistently attempt to communicate with others. While the child may have trouble articulating speech sounds, other deficits may impact their communication skills more severely. 

Speech Therapy for Improving Communication Skills

Speech therapists can help children to improve their communication skills by completing an assessment, diagnosing specific speech and language disorders, and implementing effective treatment plans to improve the child’s skills. 

The Speech Therapist may work on areas such as: 

  • Strengthening oral muscles to support clearer speech.
  • Correcting speech sound errors/teaching proper articulation.
  • Comprehension of verbal language (ex: following directions).
  • Understanding nonverbal language (ex: interpreting facial expressions).
  • Communicating with others.
    • Verbally, through producing words and sentences
    • Nonverbally, through the use of signs, gestures, pictures, and Augmentative Alternative Communication (AAC) 
  • Social communication skills (ex: being able to participate in conversations) 

Seeking professional help from a Speech Therapist is critical in improving a child’s communication skills. The therapist can also provide parents with recommendations for strategies and activities to practice at home with the child. 

Other Methods of Help with Speech Problems 

In addition to Speech Therapy, other methods can successfully help improve a child’s speech difficulties. These include: 

  • Reading aloud. Parents can model accurate articulation of speech sounds and how to form sentences. 
  • Home practice of speech exercises. Consistent practice of recommended exercises (such as oral muscle strengthening or practicing specific sounds/words) can accelerate a child’s progress towards improving their speech. 
  • Play games. Educational games and activities that involve communication can motivate a child to practice speech skills (ex: board games which involve asking or answering questions). 
  • Sing songs. This is a fun way for a child to practice producing speech sounds and can help with using rhythm and melody appropriately. 
  • Incorporate technology through articulation games/apps. Technology is often engaging for children. Playing games and apps while practicing speech sounds aloud can improve a child’s skills. 
  • Monitor progress. Parents should keep track of what skills the child gains and which areas of concern they have. This involvement can enhance the effectiveness of interventions. 

Using Forbrain to Help with Autism Spectrum Disorder and Speech Delays

Forbrain, an auditory stimulation headset, can be considered as a revolutionary approach to addressing Autism Spectrum Disorder and speech delays in children. Forbrain is intended to enhance speech therapy interventions by allowing children to hear and process the sounds they produce, louder and more clearly. 

By utilizing bone conduction technology, Forbrain delivers personalized auditory stimulation. It’s designed to refine articulation, language comprehension, and overall communication skills. 

Parents and therapists can learn more about how Forbrain can be used with children with autism on the Forbrain blog. The Forbrain YouTube channel provides valuable insight into the science behind this innovative tool and its use with children with speech and language delays. 

Final Words

Navigating the differences between a speech delay and autism can be challenging, though critical for helping a child improve their communication skills. 

It’s important to keep in mind that although a speech delay is a symptom of autism, not all children with a speech delay have autism. The two disorders can be distinguished by determining whether a child shows the two core characteristics of Autism; difficulties with social communication and the presence of restrictive repetitive behaviors. 

Seeking services from a Speech-Language Pathologist is crucial when a speech delay or autism are suspected. This, along with the use of other specified methods, and incorporating specialized tools such as Forbrain, can help children with speech delays or autism improve their communication skills. This can enhance their ability to participate in academic and social situations, and enhance their overall wellbeing. 


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Lordan, R., Storni, C., De Benedictis, C. (2021, August 20). Autism Spectrum Disorders: Diagnosis and Treatment. Autism Spectrum Disorders. DOI: https://www.ncbi.nlm.nih.gov/books/NBK573609/?report=printable

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Amy Yacoub

Amy Yacoub, MS, CCC-SLP is a Speech-Language Pathologist. She has over 12 years of experience working with children who have a variety of diagnoses and disorders, including speech and language delays, Childhood Apraxia of Speech, and Autism. She is also an experienced consultant within the field.