Ataxia (generally speaking) is simply the inability to properly coordinate muscles; It is experienced when trying to make voluntary movements such as walking, picking up objects, speaking, swallowing (think about it, there are a lot of muscle movements involved in speaking), or even controlling your eyes.
How Can Ataxia Affect Motor Coordination?
Ataxia can most often be attributed to a lesion in the cerebellum, the part of your brain which (among other things) helps control the coordination of muscles. Most people with Multiple Sclerosis see this present when they try to walk; they may feel unsteady, lean from side to side, or even stumble. Ataxia is also noticed when trying to complete fine motor tasks; buttoning your shirt, writing your name, or even typing on the computer. When you think “I am going to button my shirt up” usually your cerebellum almost instantly plans out the necessary motor movements in your hands to complete this task. With ataxia, the planning of these movements is disrupted which makes you have to struggle to get your hands to do what you want them to do. This is a huge part of why I stopped playing the piano and guitar; I just couldn’t hit the right notes without having to pause which disrupted the steady and smooth flow of notes that makes music what it is.
How Can Ataxia Affect Speech?
As I noted above, ataxia can also affect your speech. It is important to understand that ataxia is not the primary cause of most speech problems in MS; dysarthria (presenting as slurred speech) or dysphonia (which has more to do with respiration and the vibration of your vocal cords) are different than how ataxia affects your speech and also may not originate in the cerebellum. When you speak, the many muscles involved in this task are disrupted just the same as when you are trying to complete fine motor tasks. Your cerebellum just isn’t planning how you need to use each muscle to produce the right sound. Certain sounds may be easier to produce than others which is why sometimes, someone experiencing an inability to speak smoothly due to ataxia, can pronounce certain syllables in a word just fine but will have to pause and try really hard to pronounce another syllable. The smooth rhythm in speech that should be produced is disrupted much like the smooth sound of music being played on the piano is disrupted when there is a lack of fine motor skill. This unsteady speech (requiring frequent pausing to pronounce various syllables) is known as “scanning speech”.
How Can Ataxia Affect Vision?
Ataxia can also affect the eyes which can (for example) cause involuntary back-and-forth eye movements known as nystagmus due to the inability to properly coordinate the eye muscles. Again, it is important to understand that this is not the primary (or most common) cause of nystagmus; the visual system is very complex and can be affected by many different parts of the brain so ataxia is just one of the many things that can cause nystagmus.
How do you Treat Ataxia?
There is no pill you can take specifically for ataxia. You generally have to treat the underlying cause which in MS is a lesion flaring up. Like the treatment of many other MS symptoms, steroids and time are really the only options here. Of course for long lasting ataxia, physical and occupational therapy along with adaptive devices such as a cane/walker, modified utensils for eating, tools to help button up clothing, or communication aids can most certainly be of help.