Speech - What's typical and what isn't

Phonetics/Phonology 101

When most people hear “speech therapy,” they often think of pronunciation or “speech impediments.” Phonetics refers to the study of how we physically produce the sounds in words, while phonology refers to our cognitive realization of these sounds. Our vocal mechanism and mouth produce sounds that are perceived together as words. When two words only differ by one sound, they are considered minimal pairs. For example, “bat” and “rat” differ only by the “b” sound and the “r” sound. “Bat” and “rat” are minimal pairs, and the “b” sound and “r” sound are phonemes. All languages have phonological rules. For example, when you say “pie,” you aspirate on the “p” sound or puff out air, but if you say “spy,” you don’t. A note on how we write and talk about phonemes. The International Phonetic Alphabet (IPA) is used by linguists and SLPs to clearly denote a specific phoneme instead of writing with orthographic letters. For example, the “c” in “cat” corresponds to the IPA symbol /k/.

When discussing phonemes, we divide them into place and manner of articulation and voiced and voiceless. Place of articulation refers to where phonemes are produced in the mouth.

• Place: Bilabial sounds are produced with the lips (e.g., p, b, m, w). Labio-dental sounds involve the teeth and lips (e.g., f, v). Interdental sounds involve the tongue pressing on the top teeth (e.g., th). Alveolar sounds are produced on the ridge behind the top teeth (e.g., t, d, n, s, z). Post-alveolar and palatal sounds are produced behind that ridge (e.g., sh, zh, y). Velar sounds are produced near the soft palate toward the back of the mouth (e.g., k, g, ng), and glottal sounds are produced using the vocal tract (e.g., h).

• Manner: Plosive sounds are known as “stops” because they are produced by stopping airflow with the articulators (e.g., p, b, t, d). Nasal sounds are produced by allowing air to enter the nasal cavity (e.g., n, g, and ng as in “ring”). Fricatives (air-stream sounds) are produced by allowing air to flow through the articulators (e.g., f, v, s, z, sh). Liquid and glide sounds are similar to vowels but with more constriction (e.g., r, l, w, y). Finally, affricate sounds are produced using a combination of stopping and airflow (e.g., ch, j).

Obviously, we’re not born saying all of these sounds. As a child, we gradually learn to perceive and say the phonemes in our language. First, we will review typical speech sound development and then discuss when you may need to consider therapy.

Speech Development

The table below shows the age at which 50% and 90% of children produced each sound correctly across word positions. As you can see, there is quite a variation; however, most children produce all sounds by age five or six. Each sound is listed with the common orthographic spelling and IPA symbol if they are different.

*When considering intelligibility percentages, it is important to note that parents often overestimate their children’s speech intelligibility. It can be helpful to listen to the feedback from less familiar listeners.

Ages 1-2

What to expect: By age 2, children are producing a variety of early developing consonant sounds, including p (as in “pop”), b (as in “ball”), m (as in “mama”), h (as in “hi”), t (as in “top”), d (as in “dada”), and n (as in “no”). These particular speech sounds are produced toward the front of the mouth. You can get face-to-face with your toddler and model short, simple words with these target sounds, all while encouraging your toddler to look at your mouth while you slowly say the word. You can also gently place your child’s hand on your mouth as you say the word or sound over and over again (example: “pop pop pop the bubbles!”). If your toddler is still working on producing some of these earlier developing sounds, they may just need more intentional moments of exposure and opportunities to practice their new sounds as they develop.

Tips: Sometimes, toddlers can be hard to understand, which is totally normal as their speech sound system continues to develop. However, if you sometimes struggle to understand your toddler, here are some tips to try:

• Get down on their level and try to determine what they are looking at/paying attention to.

• If your child is pointing or referencing an item, person, or location, follow their point and model simple language about what they could be talking about.

• Acknowledge their communication attempts (e.g., “I hear you…” or “I’m listening…”).

• Give it your best guess: If your child uses jargon and you can pick out one or two true words, pull them out and model those single words back to your child

• Admit defeat: It’s okay to sometimes tell your child, “I’m sorry, but I can’t understand you right now, but I’m trying…”

• Encourage your child to show you by modeling “show me” and then follow their point

When toddlers are learning new words and speech sounds, they won’t produce the sounds or words perfectly, and that’s okay! We want to continue to keep communication positive and pressure-free. So, if your toddler makes a mistake and says “buh” for “ball,” you can simply smile and model back to them, “Ball! That’s the big ball,” as opposed to correcting them.

Early signs of a speech sound disorder in young toddlers could include:

• If a child is not saying p, b, m, h, and w correctly most of the time by two years

• If a child is not saying k, g, f, t, d, and n correctly most of the time by three years

Age 3

What to expect: At age 3, children may be less than 50% intelligible. Children at this age are producing or beginning to produce sounds like p, b, t, d, k, g, m, n, f, s, h, and w.

Tips: Model great speech! Get on your child’s visual level to ensure they can see your face when you are modeling words.

Age 4

What to expect: By age 4, most children are 50% intelligible, according to a recent study by Hustad et al. as reviewed by The Informed SLP [1].

In addition to the sounds listed above, children at this age are producing or beginning to produce sounds like ng, v, z, sh, y, l, ch, and j

Tips: Continue modeling new words. Clap out syllables for longer words. Often, children have an easier time starting at the end of the word and building to the front when practicing longer words. For example, “fant”, then “lefant”, then “elephant.”

Age 5

What to expect: 75% intelligible by five years

In addition to the sounds listed above, children at this age are producing or beginning to produce sounds like voiceless th, zh, r.

Tips: If your child mispronounces a word, recast it back to them without expecting them to repeat it. If your child says, “Wow, look at the tat” you can say, “Oh wow, there is a cat”. Practice phonemic awareness skills by having your child generate rhyming words or words that start with the same sound. Identify the letter that goes with the sound.

Age 6+

What to expect: 90% of children are intelligible past age 7. By age 6-7, most children are producing all sounds. Some children may still be learning voiced th and r.

Tips: If your child struggles significantly with sounds, it may be best to contact a speech therapist. Start by contacting your child’s teacher to connect with your school SLP. You can contact a private speech-language pathologist if your child does not qualify for speech services at school.

Examples of Atypical Development

A child’s speech may not follow the typical developmental path for various reasons, including but not limited to the following:

• Structural differences can contribute to how a child’s speech sounds and how it develops. Examples of structural differences impacting speech include but are not restricted to tongue tie (ankyloglossia), craniofacial anomaly, and cleft lip and palate.

• Oral-motor tone (dysarthria) or function divergences can also influence a child's speech production. For example, variations might arise secondary to Down syndrome, autism, or cerebral palsy.

• Articulation disorders refer to differences in sound production due to motor differences. A common example of this is “w” for “r” “wabbit” for “rabbit.” Another example of an articulation disorder is an interdental lisp (e.g., “thee” for “see) or a lateral lisp where the “s” sound is distorted due to lateral airflow. While some articulation errors are developmentally appropriate, an error like a lateral lisp is considered atypical regardless of age and likely warrants speech therapy.

Phonological disorders refer to differences in sound production due to linguistic differences. These errors might appear as the child's consistent phonological rules, like producing all back sounds in the front (a phonological process known as fronting). This would sound like “dee” for “key.” Other signs of phonological disorder include omitting sounds at the end of words, collapsing syllables (e.g., “nana” for “banana”), reducing consonant clusters or blends (e.g., “side” for “slide”), and assimilating sounds in words (e.g., “tat” for “cat”).

• Childhood Apraxia of Speech (CAS) is defined as “a neurological childhood (pediatric) speech sound disorder in which the precision and consistency of movements underlying speech are impaired in the absence of neuromuscular deficits (e.g., abnormal reflexes, abnormal tone). CAS may occur as a result of known neurological impairment, in association with complex neurobehavioral disorders of known and unknown origin, or as an idiopathic neurogenic speech sound disorder.” [3] Having a skilled Speech-Language Pathologist engaged in the differential diagnosis is crucial, given that Childhood Apraxia of Speech (CAS) and severe phonological disorders can be misdiagnosed for one another. A correct diagnosis is essential to establish the most optimal and tailored treatment approach. A hallmark of CAS is the inconsistent production of sounds due to challenges in motor coordination. While an articulation disorder has to do with difficulty with correct placement/manner for specific sounds, and phonological disorders involve challenges associated with the cognitive realization of those sounds, apraxia involves the brain's ability to coordinate the movements.

• Stuttering refers to dysfluencies in speech such as interjections (e.g., um, uh), part-word or whole-word repetitions (e.g., “b-b-b-ball”), prolongation of sounds in words, and blocks when speaking. Technically, everyone stutters, but some individuals exhibit more stuttering than others or less typical types of stuttering.

Do you have concerns about your child’s speech? Coneect with Branch Out Therapy today! Complete the contact form and I will reach out to you to answer any questions you have about pursuing a speech and language evaluation or therapy. Branch Out Therapy provides services at the Be Well Collective located at 3246 Henderson Rd. as well as in homes, schools, and daycares.

A portion of this blog post was written by Olivia Crawford, a pediatric speech-language pathologist and owner of Little Sprouts Speech Therapy. In her work, Olivia supports “late talkers” or those toddlers who need a bit of support in meeting their expressive communication milestones. She combines direct intervention with caregiver coaching and provides therapy within a child-led, play-based framework. To learn more about Olivia and her work, please visit her website at www.littlesproutsspeech.com.

Sources

1. Jennifer Yoshimura, MA, CCC-SLP. (2021, October 11). Into intelligibility? Here’s intel. [Review of Speech development between 30 and 119 months in typical children I: Intelligibility growth curves for single-word and multiword productions by Hustad, K. C. et al.] The Informed SLP. https://www.theinformedslp.com/review/into-intelligibility-here-s-intel

2. American Speech-Language-Hearing Association (n.d.) Speech Sound Disorders: Articulation and Phonology. (Practice Portal). Retrieved month, day, year, from www.asha.org/Practice-Portal/Clinical-Topics/Articulation-and-Phonology/.

3. American Speech-Language-Hearing Association (n.d.). Childhood Apraxia of Speech (Practice Portal). Retrieved month, day, year, from www.asha.org/Practice-Portal/Clinical-Topics/Childhood-Apraxia-of-Speech/.

4. Dimitrios, (2023). Main Places and Manners of Articulation [Image]. Adobe Stock. https://stock.adobe.com/images/main-places-and-manners-of-articulation/484269112