The COVID-19 pandemic has had a profound impact on nearly all aspects of life. As it relates to speech and language development, the unintended effects of nearly two years of habitual mask-wearing may only be starting to emerge.
The first few years of a child’s life are the most critical for language development. Children rely heavily not only on what they hear, but on what they see. They imitate how sounds are made by listening and watching lip and mouth movements. Increased mask-wearing in school and daycare settings means children are unable to observe their caregivers speaking and have to rely only on what they hear. For children who are struggling with speech, there is the potential for them to have prolonged or continued speech difficulties, especially if errors are not immediately caught by caregivers.
Sound errors where we see the difference, more than we hear it, are most likely to go undetected for longer periods of time or go unnoticed altogether due to mask-wearing. That is, sounds produced with the same type of airflow but different contact points along the vocal tract are the ones most easily confused with each other when visual information is hidden behind a mask.
N and M
In a classroom today, a child may hear their teacher say a new word starting with an N. However, since the mouth is covered, the child might perceive it as an M and go on to reproduce it that way.
The only difference between an M and an N sound is where it is created in the mouth. The N is made by raising the tip of the tongue to just behind the teeth, whereas the M is created by bringing both lips together. When watching someone speak, the difference between an N and an M sound is easy to see. Without visual information, however, there is the potential for confusion.
B and V
Similarly, a child may start to learn the letter V, but without seeing the adult model the upper teeth touching the lower lip position, they may hear and then produce a B sound.
B is made by bringing both lips together and releasing the air with a pop, while V is made by bringing the bottom lip and upper teeth together and letting out a long stream of air. The difference in the flow of air may not be readily apparent by ear and the visual difference is undetectable behind a mask.
S and TH
Sounds S and TH (as in ‘thing’) are created with a long continuous stream of air, with a difference in the placement of the tongue. S is made by raising the tip of the tongue behind the upper teeth, and TH is created by placing the tongue between the teeth. By ear alone, the noisy airflow of each can sound similar, which may delay the detection of a frontal lisp (S becoming TH).
T, D, K, and G
T, D, K, and G (as in ‘goal’) are all sounds made by stopping and releasing air in a short burst. T and D are made at the front of the mouth, while K and G are made at the back near the throat. Without the mouth visible, front and back sounds can seem similar, meaning a T can be confused with a K, and a D with a G. If a young child does not learn to distinguish these sounds by watching and listening, they may go on to produce all sounds of this type only at the front or only at the back.
How can I support my child?
Even as restrictions are lifted, masks will continue to be a part of every day living for the near future.
It is therefore particularly important to monitor your child's emerging sounds. This sound development chart from Mommy Speech Therapy shows what sounds children should be in the process of developing according to their age.
When it is safe to do so, give your child mask-free communication opportunities where they can hear and see people talking. It is also important to increase face-to-face communication with your child at home.
What does the research say?
Children with conditions that make them more reliant on visual cues are at a greater disadvantage:
Face masks can cause speech processing difficulties:
Increase face-to-face time with your baby at home: