The Lingual Hokey Pokey
(AKA the importance of lateral tongue movements in learning to eat solids)
Like many of the other structures in our bodies, we don't think very much about what our tongue does. It just quietly does its job, and we only notice if something goes wrong. But next time you speak to someone, or eat, or drink - pay attention to the movements of your tongue. It really is an amazing group of muscles. It can move in any direction, it is very strong for its size and it works really hard for us, tasting, cleaning our mouth and teeth, keeping our lips hydrated, and supporting speech, eating and drinking.
The last few weeks I've found myself talking to a few parents about the importance of lateral (sideways) tongue movements. A lot of the time when a child is gagging on lumps, or not chewing and swallowing foods whole, reduced lateral tongue movement is the culprit.
Think about it (and maybe get a cracker, because this works better when you actually do it as you think about it). Usually you place food front and centre in your mouth, because your front teeth are great for tearing and cutting pieces of food off. But once you've got a bit off, what do you need to do? Chew it, of course. And where do we chew? On our molars, which are towards the back at the sides of our mouth.
So once the food goes in, we need a way to transport it from the middle of the mouth to the side, and that is where lateral tongue movements come in. Our tongue picks up the food and deposits it on our molars so we can chew it. As bits escape, the tongue scoops them right back up and delivers them back to the molars. Once everything is chewed up, our tongue collects all the bits back into the middle of the tongue so it can send them cascading down into our throat (that's the first part of a swallow).
Very little babies really only know how to move their tongues forward and back (to suck), and in concert with their jaw. They can't move their tongue side-to-side independent of their jaw. That's a more sophisticated motor skill, and it will be a while before it starts to develop. Typically, it kicks off around the time when babies are establishing solids. How convenient! Sometimes, though, it takes a while longer to develop, or doesn't develop independently at all. So when the food goes into the baby's mouth, they have no way of mashing it up and it stays lumpy. They may then spit it out, or try to swallow it (sometimes triggering a gag), or just roll it around, hoping it will break down eventually.
Luckily there are ways we can support our babies to develop lateral tongue movements and so improve how they manage solids. There is a very handy reflex called the transverse (or lateral) tongue reflex which means that up until 6-9 months, many babies will move their tongue sideways when they feel touch to that side of their tongue. To support lateral tongue movements, we can tap into this reflex.
What I recommend is allowing and encouraging your baby to mouthe stick-shaped items, which will touch the side of their tongue and encourage those lateral movements. Stick shaped items like:
- Teethers and spoons - the Pigeon toothbrush trainer set (http://www.pigeonbaby.com.au/healthcare.php - available in many pharmacies) is a great example. I'm a big believer in learning to eat by eating, so level up by dipping these teethers/spoons in puree and allowing your baby to suck it off.
- 'Hard munchable' foods - whole raw carrots, spears of dried papaya or mango, beef jerky, lamb chop bones
- Dissolvables - potato stix (http://www.healtheries.com.au/product/kidscare-potato-stix/ - available in the baby or health food section of Coles and Woolies), veggie straws (http://www.amazon.com/Sensible-Portions-Garden.../.../B0093JX9RA - available from Costco), Baby Mum Mums and other rusks.
As always, with baby feeding therapy at Ready Step Grow, keep it child led. Place the items on their high chair tray or on the table in front of them, let them bring it to their mouth, and keep everything calm and low pressure. Inevitably with mouthing of stick shaped items, they will trigger a few gags. When that happens keep calm and remember, gagging is an important part of development (https://www.facebook.com/groups/423273087757162/permalink/865526766865123/). They'll figure out their limits eventually.
tl:dr? Here are the key points.
- Sideways tongue movements are important for managing lumps
- Lack of sideways tongue movements can lead to gagging and spitting out lumps
- You can support sideways tongue movements by encouraging your baby to mouthe stick shaped items and foods.
Katherine Sanchez (RSG Speech Pathologist)