Taste changes in HD
Many HD families have talked about our loved one with HD going through periods where their tastes buds seem to have changed. Something once loved is suddenly thought horrible/no longer desired, etc.
The following is a very simplistic explanation (written for young people) on our taste buds. It shows how the nose and tongue are involved in getting signals to the brain.
Some key things are:
- Some things can make your taste bud receptors less sensitive, like cold foods or drinks
- Identifying tastes is your brain's way of telling you about what's going into your mouth (could this signal be miswired in HD?)
- People are born with about 10,000 taste buds. But as a person ages, some of his taste buds die. (some medications can change tastes)
- the tongue can't take all of the credit for tasting different flavors - it has help from your nose.
- Strong smells can even confuse your taste buds
- A dry tongue can't taste a thing, so saliva helps the tongue by keeping it wet.
- If you suck on an ice cube before you eat a food you don't like, you won't notice the bad taste. Try it next time you have to take medicine that you can't stand!
Has anyone ever told you that the tongue is a muscle? Well, that's only partly true: the tongue is really made up of many groups of muscles. These muscles run in different directions to carry out all the tongue's jobs. The front part of the tongue is very flexible and can move around a lot, working with the teeth to create different types of words.
This part also gets into the action at lunch: it helps move food around your mouth while you chew. Next time you take a bite of your favorite food, pay attention to what your tongue is doing. You'll feel it push the food to your back teeth so the teeth can grind it up.
The muscles in the back of your tongue help you make certain sounds, like the letters "k" and hard "g" (like in the word "go"). Try saying these letters slowly, and you'll feel how the back of your tongue moves against the top of your mouth to create the sounds. And remember how the front of your tongue pushed that food to your back teeth to be ground up? Once the food is all ground up and mixed with saliva (say: suh-ly-vuh), or spit, it's time for the back of the tongue to do its thing.
The back muscles of the tongue move and push a small bit of food along with saliva into your esophagus (say: eh-soff-uh-guss), which is like a food pipe in your throat. But also in the throat is the windpipe, which
allows air to come in and out of your body. When you swallow, a special flap called the epiglottis (say: eh-pi-glot-iss) drops down to cover your windpipe. This keeps the food from "going down the wrong way"- into the windpipe instead of the esophagus.
Don't put that mirror away yet! Look at your tongue again, but this time look closely at the top of it. Notice how it's rough and bumpy - not like the underside, which is very smooth. That's because the top of your tongue is covered with a layer of bumps called papillae (say: pap-ill-ee).
There are three major different types of papillae - two in front and one in back. At the front of the tongue are fungiform (say: fun-ji-form) papillae and filiform (say: fill-ee-form) papillae. The larger ones are the fungiform papillae, and the smaller ones that look a little bit like hair are the filiform papillae. At the back of the tongue are the vallate (say: va-late) papillae. They are large and round, and there are about eight to 12 of them
Papillae help grip food and move it around while you chew. And they contain your taste buds, so you can taste everything from apples to zucchini! People are born with about 10,000 taste buds. But as a person ages, some of his taste buds die. (An old person may only have 5,000 taste buds!) That's why some foods may taste stronger to you than they do to an adult.
Taste buds on some parts of the tongue respond to certain flavors, while taste buds on other parts are sensitive to other flavors. There are four main flavors that the taste buds can taste.
-Taste buds at the back of the tongue (contained in the vallate papillae) taste bitter foods like unsweetened chocolate (the kind that's used for baking).
-Taste buds on the side taste sour foods like lemons.
-Taste buds at the tip of the tongue taste sweet foods like cookies and salty foods like pretzels.
Many times, a taste is made possible by a combination of these four different taste areas. Next time you are eating dinner, give your taste buds a test. First try to taste different flavors with the appropriate parts of
your tongue. Then try to trick your taste buds and put something sour on the tip of your tongue or something sweet on the sides.
So how do you know how something tastes? Each taste bud has microscopic hairs called cilia (say: sill-ee-uh) sticking out of it. The cilia are covered with special receptors that are very sensitive to things around them.
When you put something in your mouth and it begins to dissolve in saliva, this stimulates the cilia to start making nerve signals. These signals then travel to the brain, where the brain can interpret the signals and identify
the taste for you.
Identifying tastes is your brain's way of telling you about what's going into your mouth, and in some cases, keeping you safe. Have you ever taken a drink of milk that tasted funny? When the milk hit the receptors, they
sent nerve impulses to your brain: "Milk coming in - and it tastes funny!" Once your brain unscrambled the nerve impulses, it recognized the taste as a dangerous one, and you knew not to drink the milk.
Some things can make your taste bud receptors less sensitive, like cold foods or drinks. A popsicle made from your favorite juice won't taste as sweet as plain juice. If you suck on an ice cube before you eat a food you don't like, you won't notice the bad taste. Try it next time you have to take medicine that you can't stand!
Friend of the Tongue
Last time you had a cold and your nose felt stuffed up, did you notice that foods didn't taste as strong as they usually do? Well, that's because your tongue can't take all of the credit for tasting different flavors - it has help from your nose. Your nose helps you taste foods by smelling them before they go in your mouth and as you chew and swallow them. Strong smells can even confuse your taste buds: try holding an onion slice under your nose while eating an apple. What do you taste?
Your tongue also gets help from your teeth, lips, and mouth. Your teeth help your tongue grind food as the tongue mixes the food around your mouth. And without your teeth, lips, and the roof of your mouth, your
tongue wouldn't be able to form sounds to make words.
Saliva is also a friend of the tongue. A dry tongue can't taste a thing, so saliva helps the tongue by keeping it wet. Saliva also breaks down food
so the tongue can help you swallow the food more easily after it's been chewed.
The Nose: http://www.kidshealth.org/kid/body/nose_SW.html