Conquering the ‘slushy’ /S/: Your guide to treating lateral lisps
As a speech therapist, few things are as rewarding as helping a child find their clear, confident voice. Among the various speech sound disorders, the ‘lateral lisp’ – often described as a ‘slushy’ or ‘wet’ /S/ sound – presents a unique challenge. While it can be tricky to treat, I’m thrilled to share that I’ve had significant success in helping children overcome this particular hurdle.
What is a lateral lisp?
Most people are familiar with a frontal lisp, where the tongue protrudes between the front teeth, resulting in a /TH/ sound for an /S/ (e.g., ‘thun’ for ‘sun’). A lateral lisp, however, is different. Instead of the air escaping over the front of the tongue, it escapes over the sides, often giving the /S/ and /Z/ sounds a distinct, muffled, or ‘slushy’ quality. This happens because the tongue is not forming the correct central groove, allowing air to spill out laterally.
The science behind a perfect /S/ vs. a slushy one
To understand how to fix a lateral lisp, it’s helpful to understand how a ‘perfect’ /S/ sound is made. Imagine a narrow, focused stream of air. For a clear /S/ sound, your tongue forms a shallow groove down its centre, directing a precise, thin stream of air right down the middle, over the tip of your tongue, and out through a tiny opening between your tongue and the roof of your mouth, just behind your front teeth. This focused airflow creates that crisp, sharp /SSSS/ sound we recognise.
Now, picture what happens with a lateral lisp. Instead of that neat, central channel, the tongue is often flatter or positioned in a way that allows the air to escape over one or both sides. Think of it like a river overflowing its banks – the air, instead of flowing in a controlled stream, spills out sideways, creating that characteristic ‘slushy’ sound. This lateral airflow is what we need to retrain.
Why is it tricky to treat?
Treating a lateral lisp can be challenging for a few reasons:
- Habitual muscle memory: The way the tongue moves and positions itself for a lateral lisp is deeply ingrained. It’s a motor habit that needs to be unlearned and replaced with a new, more precise movement.
- Subtle differences: The difference between a lateral lisp and a correct /S/ sound can be quite subtle to perceive, both for the child and sometimes even for parents. This makes it harder for the child to self-monitor and correct.
- Oral motor control: It requires fine motor control of the tongue muscles to create and maintain that central groove for airflow.
My success with children aged six years and over
I’ve found great success in treating lateral lisps, particularly with children aged six years and older. Why this age group? By this age, children typically have:
- Increased awareness: They are more aware of their speech and often more motivated to make changes. They can better perceive the difference between their ‘slushy’ /S/ and a clear one.
- Improved cognitive skills: They can understand and follow more complex instructions and strategies.
- Better self-monitoring: Their ability to listen to themselves and correct their own speech improves significantly.
- Enhanced oral motor control: Their fine motor skills, including those of the tongue, are more developed, allowing for greater precision.
My approach focuses on a combination of auditory discrimination, tactile cues, and targeted myofunctional exercises to help children ‘feel’ the correct airflow and tongue placement. We use a variety of engaging activities to make the process fun and effective.
It is crucial to understand tongue functioning and focusing on correcting improper oral resting posture and muscle function, which are often significant contributors to a lateral lisp. For example, if the tongue rests low and wide in the mouth consistently, or if there’s a tongue thrust during swallowing, these habits can prevent the tongue from achieving the precise, midline placement necessary for a clear /S/ or /Z/ sound. Through targeted exercises I aim to re-educate the oral and facial muscles, promoting correct tongue posture at rest, during swallowing, and, ultimately, during speech production. By strengthening the muscles responsible for tongue lifting and encouraging a more appropriate swallowing pattern we can establish the correct oral motor skills needed to overcome a lateral lisp and achieve clearer articulation.
The recipe for success: Little and often
The single most crucial ingredient for success in treating a lateral lisp is daily home practice of all the strategies given. This isn’t about long, arduous sessions; it’s about consistency. Think of it like building a muscle: short, frequent workouts yield better results than sporadic, intense ones.
My recommended formula is ‘little and often’. This means:
- Short, focused sessions: Aim for 5-10 minutes of practice, 2-3 times a day. This prevents fatigue and keeps the child engaged.
- Integrate into daily routines: Practise while waiting for dinner, during a car ride, or before bedtime. Make it a natural part of their day.
- Positive reinforcement: Celebrate every small success! Encouragement goes a long way in building confidence and motivation.
- Parental involvement: Parents play a vital role in providing consistent cues and encouragement at home. I equip families with clear, easy-to-follow strategies.
Overcoming a lateral lisp requires dedication, but with the right guidance and consistent practice, a clear, confident /S/ sound is achievable. If your child is struggling with a ‘slushy’ /S/, please don’t hesitate to reach out. Together, we can achieve success!
Sonja McGeachie
Highly Specialist Speech and Language Therapist
Owner of The London Speech and Feeding Practice.
Find a speech and language therapist for your child in London. Are you concerned about your child’s speech, feeding or communication skills and don’t know where to turn? Please contact me and we can discuss how I can help you or visit my services page.
