How Speech Patterns in Autism Can Affect Communication

Virtually all people with autism have problems with spoken language. This is true even for those people who have no speech delays or difficulty with pronunciation. That's because spoken language involves more than the use of words; we vary our pitch, loudness, tempo, and rhythm in our speech in order to convey different meanings. These changes are called "prosody," and people with autism often find prosody difficult to hear, understand, or reproduce. What this means is that even people with very high functioning autism may not truly understand what is being said, or may say things in such a way that they are misunderstood.

Kids playing together with telephone cans
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How Prosody Works

Prosody is an important tool for communicating meaning. In fact, without an understanding of prosody, it's easy to completely misunderstand another person's words. To better understand how prosody works (and why it's so important), try saying the word "really" five times in a row, changing the meaning each time as follows:

  • How cool is that?!
  • I don't believe you.
  • I'm shocked.
  • I'm delighted.
  • I'm telling the truth.

If you did this exercise, you changed your prosody at each repetition of the word, even though your pronunciation of the word (REE-lee) remained the same. In some cases your voice went up or down on different syllables or to a varying degree; in other cases, your voice was louder, quieter, faster, slower.

Why Prosody Can Be Confusing for People With Autism

When people with autism use spoken language, they usually use it quite literally. As a result, sarcasm, irony, idioms, metaphors, and similes may go right over their heads, as do subtle differences in meaning.

It's easy to understand why this would be the case. Prosody is learned through observation and imitation rather than through instruction. While there are rules of prosody they are rarely expressed aloud—and they may vary depending on the situation or the cultural setting. People with autism rarely learn social communication skills through imitation alone, so if they're not actively taught the rules of prosody they may never learn them.

Why Prosody Matters

Because many verbal people with autism have high IQs and huge vocabularies, difficulties with prosody and language use aren't always obvious—because the speaker isn't obviously disabled. The outcome is that conversational partners may be unintentionally offended or confused, resulting in hurt feelings and negative interactions. For example, statements like the following can mean many different things depending on the tone, context, and body language; misunderstanding can have serious consequences.

  • A friend says "I love you!" (but means "I love the fact that you agreed to do something for me")
  • A co-worker says "Are you really done with this project?" (but means "you didn't finish this project and should recheck for errors")
  • A store clerk says "You have to buy this" (but means "I want you to buy this, and am trying to persuade you to do so")

In addition:

  • People with autism may find it very hard to use prosody to express multiple or subtle meanings, thus limiting their own ability to communicate. This can lead to a myriad of social communication issues ranging from embarrassing gaffes to accusations of verbal assault or stalking.
  • Many people with autism lack the ability to use prosody and thus have what is often described as a "flat" voice. This is sometimes misinterpreted as a lack of interest, lack of intelligence, lack of humor, or lack of emotional response. In fact, many people with autism are extremely emotionally sensitive; many are artists, poets, and composers whose emotional sensitivity comes out in their art. And many people with autism have terrific senses of humor. But a flat voice, combined with a lack of verbal expressiveness, can easily be misinterpreted.
  • It's extremely easy for people with autism to misunderstand how language is being used; this can lead to serious problems with relationships and can make autistic people vulnerable to those who wish to mislead them.

Resources for Improving Use and Understanding of Prosody

There are no full-fledged therapies developed to help people with autism overcome deficits in prosody, though experimental approaches are under investigation. If you are interested in exploring possible directions for improving prosody, you may wish to explore:

  • Music therapy to work on rhythm and pitch
  • Pragmatic speech therapy to expand conversational skills
  • Social skills therapy to improve the understanding of body language and context
  • Drama therapy to practice interaction in a safe, scripted manner
2 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Institute on Deafness and Other Communication Disorders (NIDCD). Autism spectrum disorder: Communication problems in children.

  2. Heikkinen J. et al. Perception of basic emotions from speech prosody in adolescents with Asperger's syndrome. Logoped Phoniatr Vocol. 2010;35(3):113-120. doi:10.3109/14015430903311184

Additional Reading

By Lisa Jo Rudy
Lisa Jo Rudy, MDiv, is a writer, advocate, author, and consultant specializing in the field of autism.