Speech-Language Pathology Topics: Consonants

What are consonants and why are they important to speech?

Consonant sounds are produced by constricting or interrupting the air flow at some point during the production of a sound. In contrast, a vowel is a sound produced with a relatively open vocal tract. Consonants are combined with vowels to make syllables and words. When consonants are produced incorrectly, that makes speech very difficult to understand.

There are 24 consonant sounds used in spoken American English. These sounds may or may not match up with English letters and the phonics typically associated with those letters. Here is a chart of the 24 American English consonant sounds. The symbol on the left is the phonetic symbol most Speech-Language Pathologists use to represent each sound. On the right is an example of a word with that consonant sound. The letters used to spell the sound are in bold.

What are the characteristics of consonants

What makes a "p" different than an "v"? The consonants sound different from each other because they are made in different ways. They differ in their place of articulation, their manner of articulation, and their voicing status. Speech-Language Pathologists use a consonant chart to keep track of the consonants and their characteristics.

What are the different places of articulation?

A consonant is made by constricting the airflow between where it starts with the exhalation in the lungs and where it exits the mouth at some point. One reason sounds differ is because the point of constriction happens at different places. If the point of constriction is at the lips (/p/, /b/, /m/, /w/) then the place of articulation is bilabial. If the point of constriction is just behind the top teeth (/t/, /d/, /s/, /z/, /n/, /l/, /r/) then the place of articulation is alveolar. Here is a list of the places of articulation and a picture to help you visualize those places.

• bilabial - constriction between both lips
• labio-dental - constriction between top teeth and bottom lip
• dental - constriction between top and bottom teeth
• alveolar - constriction between the tongue and the alveolar ridge (top of mouth just behind top teeth)
• palatal - constriction between the tongue and the hard palate (roof of mouth)
• velar - constriction between the tongue and the soft palate (roof of the very back of the mouth)
• glottal - constriction at the vocal folds

What are the different manners of articulation?

A consonant is made by constricting the airflow between where it starts with the exhalation in the lungs and where it exits the mouth at some point. One reason sounds differ is because the method of constriction happens in different ways. If the airflow is completely stopped and then released in a puff of air (/p/, /b/, /k/, /g/, /t/, /d/) then the manner of articulation is a stop. If the the airflow is redirected through the nose (/m/, /n/, /ng/) then the manner of articulation is a nasal. Here is a list of the manners of articulation.

• stop - airflow is completely stopped and then released
• fricative - airflow is constricted causing slight hissing noise
• affricate - This is a combination of a stop and a fricative. First the airflow is completely stopped and then it is constricted causing a slight hissing noise with the consonant.
• nasal - airflow is redirected out the nose
• liquid - airflow is constricted significantly more than a vowel, but not enough to cause a hissing noise with the consonant
• glide - similar to a liquid, but with slight movement during the production of the consonant

What is voicing?

There is a third characteristic of consonants. /s/ and /z/ are made with exactly the same place and manner of articulation and yet they are different. /z/ is made while vibrating the vocal folds. If you place your hand on your throat while making a /z/ sound (buzz like a bee) you will feel the vibration of your vocal folds. /s/ is made without vibrating the vocal folds. If you place your hand on your throat while making an /s/ sound (hiss like a snake) you will not feel the vibration. So the third characteristic of consonants is the presence or absence of voicing.

Why are consonant characteristics important to understand when planning therapy for Childhood Apraxia of Speech?

First of all, understanding the characteristics of consonants can help you understand why some consonants are harder than others for your child. Affricates are going to be harder than stops or fricatives because they require more complicated motor planning. Words with consonants that are all produced in the same place (dot) are going to be easier than words with consonants that change place (pod). Words with consonants that move from the very front to the very back are going to be even harder(back). Voiced sounds are going to be harder than their coresponding voiceless sound because the motor planning is more complex. Speech-Language Pathologists take all of these factors into account when choosing targets for speech therapy.

You might also be interested in the following articles:

Speech-Language Pathology Topics: Vowels

Voicing Pairs

Random Example of the Complexity of Motor Planning