Why do I startle so easily?

Myoclonus - Why Do I Startle So Easily?

A while after my major relapse in 2012 (that put me in a physical rehabilitation hospital for around 6 weeks) I started developing a weird “sensory sensitivity”. This sensitivity was mostly to sound but it also had a tendency to result in me turning around to notice someone was standing behind me without my knowledge (for example).

I began to avoid loud sounds

My startle reflex was extremely sensitive to external stimuli and it was greatly impacting my quality of life! I stopped going to restaurants to avoid the sound of clashing dishes, I hated going on walks as the sounds of cars literally made me jump and almost fall, and I quickly developed a desire to never sit with my back to a door; I wanted to see who was coming into the room and leaving. A loud or simply unexpected noise literally hurt my chest; it felt as though my heart would drop and not come back up! What was going on?

Researching MS and sensitivity to sound online

I began doing lots of research both online and in the medical books. Online I quickly learned that I was not the only one who had MS and this horrible symptom. The leading theory among most of these online groups of people who experienced this symptom was that it was something called “Hyperekplexia”. It sounded similar to what I was experiencing but something was not right.

Some infants experience sensitive startle reflex

So I hit the books and my suspicion was quickly confirmed; hyperekplexia is typically a hereditary condition in infants who experience an increase a sensitive startle reflex leading to muscle tone (Hypertonia) when exposed to an unexpected stimulus such as sound. This increase in tone can cause periods of muscle rigidity that can sometimes lead to an infant's death (SIDS – Sudden Infant Death Syndrome) due to an inability to breathe. Do you see how this doesn’t quite fit into an adult with MS suddenly developing this symptom?

Asking a neurologist about my sound sensitivity

So I continued to research the possibility of a late onset of Hyperekplexia and I could only find MS patients who believed that is what they had but I knew this had to be wrong… When I was in New Jersey at an MS event, I talked to a neurologist about this symptom. He was unsure of what it might be but he knew for sure it was not Hyperekplexia. When I got back I had researched a few other things (I can’t remember what) but I got nowhere. So, I decided to ask my SoCal neurologist because if anyone knew what it was it would be this guy! I didn’t ask him at first because I just wanted to see if I could figure it out on my own you know? Haha… Anyways, I describe this symptom to him and without a moment of consideration he told me nonchalantly, “it’s called Myoclonus”.

What is myoclonus?

That’s it? It was that simple? Well what is Myoclonus exactly? For that let’s refer to the NIH (National Institute of Neurological Disorders and Stroke).1 First of all, there are several different types of Myoclonus so I want to talk about “Stimulus Sensitive Myoclonus” because that is what I have, and what most people online (who think they have some form of Hyperekplexia) probably have. Myoclonus refers to a sudden and involuntary muscle jerk and in this case, the jerk is caused by an external stimulus such as sound. Unlike Hyperekplexia, the sudden increase in tone (the muscle jerk) is followed by the muscle relaxing and NOT by the possibility of death. The NIH notes that everyone experiences some form of Myoclonus, for example, hiccups and “sleep starts” are forms of Myoclonus that healthy individuals experience.

What causes myoclonus?

So what causes Myoclonus? Well, there are many different causes but in the case of Multiple Sclerosis, it seems more likely to be the result of “head or spinal injury,” AKA brain or spinal lesions.  The exact mechanism is not fully understood at the moment, but it is believed that in cases of stimulus sensitive Myoclonus, the brain becomes overly sensitive to the signals caused by external stimuli such as sound (in a nutshell, that is).

How to treat the sound sensitivity

So after my neurologist told me a bit about all this I asked him “what, if anything, can be done about this? It’s making my life miserable” to which he replied “Klonopin”. Klonopin (Clonazepam)? Are you serious? With my insurance, a bottle of 60 pills of Klonopin is $2.00 and change! And That is supposed to turn my life from hell to normal? I was skeptical but for two bucks it was worth a shot.

My experience with Klonopin

After 2 days of taking just 0.5mg of Klonopin, the world seemed to change. No longer did I jump at loud or sudden noises. I could go to restaurants again! It was great! It makes sense, really; Klonopin is basically meant to reduce the amount of extra electrical signals in your brain so if your brain is really sensitive to signals from external stimuli, Klonopin should help calm it down! That is an extremely non-scientific explanation of what is going on but I want people to actually understand what I am saying here.

A few months later I tried going a day without it to see if it was just in my head or not. Maybe that pill was no longer necessary? I was at my desk drinking coffee when my phone buzzed off a text alert. I “jumped” and dumped my cup of coffee all over myself, my chair, and my carpet. That is why Klonopin is “my precious” in the words of Golem from “The Lord of the Rings”. Next to Tysabri, Klonopin is the medication I consider most important to improving my life.

Always check with your doctor

But what did I learn from this that I want people to understand? You can’t believe everything you read online! From what I read, it seemed like one person heard about Hyperekplexia, didn’t fully understand it, but blogged about it like it was undoubtingly the answer to this pressing question online and everyone who read that post spread the word starting a huge misconception that their noise sensitivity was this Hyperekplexia. Always check with your doctor when you are experiencing a weird symptom because all it takes is one uneducated statement to start a game of “telephone” online and point you in the wrong direction! In fact, to avoid being hypocritical, ask your neurologist about myoclonus if you’re experiencing this!

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