Children who are not able to pronounce certain sounds or words by an expected age may have a speech sound disorder. It is often difficult to understand someone with a speech sound disorder and, in many cases, it can affect a person’s social, academic, and professional development.

Broadly speaking, there are two types of speech sound disorders: functional and organic.

Functional speech sound disorders can further be broken down into articulation disorders and phonological disorders. Below we've defined each of these disorders and describe some of the key differences.

Functional Speech Sound Disorders: Articulation vs. Phonological

  • Articulation Disorders: The production of sounds involves the coordinated movements of the lips, tongue, teeth, palate (top of the mouth) and respiratory system (lungs). Children with articulation disorders have difficulty using these motor functions to physically produce the correct speech sounds. The result is the inability to form legible words past a certain age. Sounds may be distorted or swapped altogether.
  • Phonological Disorders: Phonological disorders are characterized by a regular pattern in which a person may be able to produce individual sounds correctly, but they have difficulty putting these sounds together to form words. For example, they may be able to produce the ‘d’ sound, but may swap it out for the ‘g’ sound for certain words, pronouncing “doe’ instead of ‘go.’

The Difference Between Articulation and Functional Disorders

An articulation disorder is a difficulty at a phonetic/motoric level. They have trouble making the individual speech sounds. A phonological disorder is difficult at the phonemic level (in their brain). They can say sounds correctly, but struggle to form them into words.

Compared to articulation disorders, it is often more difficult to understand someone with a phonological disorder. Many children with phonological disorders and phonemic awareness disorders (the understanding of sounds and sound rules in words) also have problems with language and literacy, which can affect their classroom performance.

Distinguishing between articulation and phonological disorders is not always easy. However, a proper diagnosis is extremely important as it will largely determine a person’s treatment plan. Therefore, if you suspect your child has a speech sound disorder, it’s imperative that you receive an evaluation from a certified speech-language pathologist (SLP), more commonly referred to as a speech therapist.

Organic Speech Sound Disorders:

With organic speech sound disorders, there is often a known cause. These fall into several categories.

  • Motor/Neurological: Motor speech disorders occur when the muscle coordination or strength is impacted. Motor speech disorders can be developmental or acquired after neurological damage, such as a stroke or traumatic brain injury.
  • Structural: Differences in the oral and facial structures can impact speech sound production, as is the case for cleft lip and palate. Structural differences can also be caused by trauma or surgery.
  • Sensory/Perceptual: Hearing impairment can subsequently cause speech sound difficulties, as children aren’t able to hear the sounds the way others produce them. Depending on the severity of the hearing loss, speech deficits may vary.

Next Steps if Your Child May Have a Speech Sound Disorder

As mentioned above, identifying the difference between speech sound disorders can is difficult for an untrained eye. This is why assessment and diagnosis by a certified speech-language pathologist (SLP), more commonly referred to as a speech therapist, is so important. Speech sound disorders can be effectively treated, and research has shown that earlier interventions lead to better outcomes.

More Information on Speech Sound Disorders

Educating yourself on speech delays is one of the most important things a parent or guardian can do to help their child. Be sure to check out our other posts for more information on speech delays.

Diagnosing and Treating Speech Sound Disorders
Children who are not able to pronounce certain sounds or words by an expected age may have a speech sound disorder. Learn more about how speech sound disorders are diagnosed, and why treatment by a Speech-Language Pathologist (SLP) is important for a child’s emotional development.