3 Types of Phonological Processes and Disorders
Speech 5 min read

3 Types of Phonological Processes and Disorders

I previously wrote a blog about Articulation Disorders and Therapy, and while writing that blog, I thought it would also be beneficial to touch on Phonological Disorders/Processes.

After receiving articulation therapy , is your child still very difficult to understand? Does their speech sound like mumbling or disjointed? If so, your child may be struggling with another speech disorder related to phonological processes.

This blog will discuss the definition of phonological processes and give you a basic overview of the different types of errors that can occur. As always, I encourage anyone reading this who suspects that their child or a child they know might be having struggling with this speech disorder to check out Speech Blubs as a supplement to your speech practice, or contact a speech-language pathologist in your area for an evaluation. 

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Definition and Explanation of Phonological Processes

Typically, these are speech patterns that developing children use when they are learning speech sounds. Young children form these patterns because they do not yet have the skills to produce the words accurately and clearly. For example, you may hear children say the word, ‘plane,’ but it comes out at ‘pane.’ They may also delete sounds in the word, such as ‘nana’ for ‘banana.’ There are many different patterns that can occur in a child’s speech, which is “normal” while their language develops.

A phonological disorder occurs when the patterns that the child is using exist beyond the period of time that “typical” children have stopped using them, or when the errors are much more different than expected. For example, a child with phonological disorder is using the phonological process of “reduplication,” like saying “wawa” for “water” by the age of 4. In speech therapy we would say that he/she is delayed because that process typically ends in children by the age of 3. 

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The excessive use of phonological patterns that are atypical can be described as a disorder because when multiple processes are used, it creates speech that is unintelligible. As a result, if you have a young child who is not speaking clearly and no one can understand him/her, it’s important to make sure they are screened for a phonological disorder and have a clear treatment plan that will address their speech errors.

I’m going to give you an overview of the most COMMON processes, and what a speech pathologist sees most frequently. Just know that there are many more processes, but for the purpose of this blog, it’s not necessary for you to know!

Different Types of Phonological Processes

Type 1: Substitutions

Substitutions – These are speech errors where correct sounds are replaced with different sounds, making the word unintelligible. 

Backing is basically when the sounds that should be produced in the front of the mouth, are replaced with sounds that are created in the back of the mouth. For example, the word /dog/ may be replaced with the word /kog/. This is usually seen in more severe phonological delays. 

Fronting is the exact opposite of backing. This is when sounds that should be created in the back of the mouth, are made in the front. For example, the child might say /toe/ for /go/. This process usually disappears in typical children by 3.5 years old. 

Gliding is the /r/ sound is replaced with the /w/ sound and the /l/ sound is replaced with a /w/ or /y/. For example, the child might say /yewow/ for /yellow/. This process is present in typically developing children until the age of 6-6.5. 

Stopping is when a sound like /f/, /s/, /ch/, or /j/ is substituted with sounds that are short and explosive, like /p/ or /d/. For example, a child might say /dip/ instead of /chip/ or /dish/ instead of /fish/. These types of substitutions should all be gone by the age of 5. 

Vowelization is exactly what it sounds like; when a sound like /l/ is replaced with a vowel sound. For example, a child might say /papuh/ for /paper/. 

Affrication is when a sound like /t/ or /d/ is replaced with the /ch/ or /j/ sound. An example of this process is saying /duice/ for /juice/. This process will disappear by the age of 3. 

Deaffrication is when the /ch/ or /j/ sound is replaced with sounds that are produced more in the front of the mouth. For example, a child might say /ships/ for /chips/. The process will stop in children by the age of 4. 

Labialization is when the child takes a sound that is not supposed to be made with the lips and makes it that way. For example, they may say /pie/ for /dye/ or /pip/ for /tip/. 

Type 2: Assimilations

Assimilations are speech errors that are produced with a child takes a sound and replaces it with sounds that are similar or that are produced in the same way, but that isn’t the correct phoneme they should be using. 

Reduplication occurs when sounds are produced repeatedly during a word. For example, the child might say /baba/ instead of /bottle/. This will disappear by the age of 3. 

Assimilation is when the child produces a sound that he or she already heard in the word. For example, they might say “dod” instead of “dog.” This process will eliminate itself by the age of 3. 

Pre-vocalic Voicing is when a voiceless consonant in the beginning of the word is replaced with a voiced consonant. The child might be heard saying /pook/ instead of /book/. This will end by the age of 6. 

Type 3: Syllable Structure

Syllable structure changes occur when a child takes a word and deletes, adds or modifies the word in some way that makes it incorrect. 

Cluster reduction is when a child takes two sounds that are produced together and replaces them with another sound. For example, the word /tree/ may sound like /tee/. 

Final consonant deletion is when the last sound of the word is left off. For example, the word /dog/ may sound like /do/. This process should stop by the age of 3. 

Initial consonant deletion is when the first sound of the word is left off. The child may say the word /oor/ instead of /door/. The deleting of the first consonant is typically seen in more severe cases of phonological disorders. 

Again, there are many more types of speech errors, but as a speech pathologist for the last 10 years, these are the most common errors that I have seen. If you suspect your child might have a phonological or articulation disorder, please get them screened or evaluated by a speech-language pathologist and check out Speech Blubs for some fun speech therapy homework!

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The author’s views are entirely his or her own and may not necessarily reflect the views of Blub Blub Inc. All content provided on this website is for informational purposes only and is not intended to be a substitute for independent professional medical judgement, advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.

  • Fronting – the term used when sounds that should be made in the back of the mouth (velar) are replaced with a sound made in the front of the mouth (alveolar)

  • My daughter has speech therapy, but the therapist said she would expect more improvement by now. She deletes constants but has improved with end constants, changes f for s and changes t and k, while when saying a word she can be quite clear in a sentence she will drop sounds. I’m just not sure what else I can be doing. We have a list we practice every day, correct or ask her to self correct . It there something else I should be looking out for. Speech has been weekly for last 9 months.

    • Hi, for more at-home practice try Speech Blubs app, it is a great tool and kids love it! Try to incorporate your speech practice in every aspect of your life — you can even turn household activities into a speech activity! The more frequent your child is exposed to certain skills, means the more skill learning carryover, which is the goal of therapy!

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