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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). 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?

Some infants experience sensitive startle reflex

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. 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.

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!

This article represents the opinions, thoughts, and experiences of the author; none of this content has been paid for by any advertiser. The MultipleSclerosis.net team does not recommend or endorse any products or treatments discussed herein. Learn more about how we maintain editorial integrity here.

  1. NIH. Myoclonus Fact Sheet. Available at: http://www.ninds.nih.gov/disorders/myoclonus/detail_myoclonus.htm

Comments

  • SierraNevadaSnowGuy
    2 years ago

    Matt, brilliant BOO! ghost sketch — it’s a memorable image for us who struggle with this symptom. Your write-up is very informative, thanks for sharing what you’ve experienced and what you’ve learned. I printed it out and shared it with a friend who was visiting and it helped me to have him read your descriptions so that he could better understand. My guess is that others with this weird symptom may also find it difficult to explain to friends, etc. — the ghost and Boo! also felt like a good “icebreaker”, something I could use as a way of introducing what for me is a very uncomfortable topic.

    I’m working with my docs to help figure out a way to dampen my startle response. Trying to avoid the benzo meds, we’ll see how that goes. Mine startles trigger “episodes” where I’m super startle sensitive, on edge, and it”s very hard to concentrate during those periods. The episodes last hours, often 1-2 days, sometimes longer. And when the episodes pass I feel pretty good (although always trying to avoid settings & situations that trigger another startle).

    One thing I’ve learned from MS is that weird neuro symptoms can come and go. I’ve had the startle thing going for about 2.5 years, and it’s gotten progressively more intense and life disruptive. . . I’m keeping my fingers crossed that it lessens on its own or we find the right combination of meds that help decrease the intensity and/or frequency of these episodes.

    Good luck to everyone out there.

  • Lori
    5 years ago

    I am so grateful to read this article. I developed this startle problem in the past 10 years since I was diagnosed with MS. I remember at times I was so startled it was actually painful. I don’t seem to do it as much as I once did, but good to know I wasn’t crazy. Thanks for your article.

  • Matt Allen G author
    5 years ago

    Yes! It actually hurt in my chest! BLAH!

  • Adriann
    5 years ago

    Thank you Matt for an excellent accounting of your journey with Myoclonus .. I too have had a major relapse and experience a highr sensitivity to certain things one being sound .. My neurologist and I have been working on subduing the worst and working our way down .. Seems everything that I had is at a heightened stage .. I was dx”d in 2001 .. Have had 5 which the 6th was from Aug. of 2013 and carried on through today .. Anyway , as of now still being positive that I will overcome and adjust !! Thank you so much for putting a name to one of my symtoms ….

  • Matt Allen G author
    5 years ago

    It’s always easier to “fight an enemy with a name”!

  • JP
    5 years ago

    A very interesting and insightful read. I have experienced this throughout life…..and sadly note that it is worse as I age. I know I have an overactive startle reaction….knowing doesnt make it ‘controllable’. Thanks for sharing this info!

  • Matt Allen G author
    5 years ago

    well, it allows you to explore the very limited options for TRYING to control it, or reduce it I should say. For ME Klonopin HELPS but doesn’t eliminate it. Even so, I would never give that medication up, it’s a Godsend for me. Other than that though, not much you can do, but knowing might make you FEEL better in the sense that you no longer have to worry if that’s the kind of person you are; I HAVE TO KNOW HOW EVERYTHING WORKS or else it drives me MAD!

  • JulesPMH
    5 years ago

    For anyone who is experiencing sensitivity to sound, there is another condition called “Hyperacusis” that involves sensitivity to sound without apparent evidence as to the cause. The primary difference between the two, from what I’ve learned, is that it does not (necessarily) involve the muscular activity, but more often results in pain, fatigue, and a multitude of other varied cognitive symptoms. In my husband’s case, loud and/or high pitched noises – our Chihuahua’s bark being the most common, and the fire alarm going off at school he most severe, he experiences what can best be described as an excruciating sensory overload, followed by a period of non-responsiveness, shaking, fatigue, and often teariness or outright crying; all of this can cause a flare-up of his MS symptoms, or even an exacerbation.
    There are a few subcategories of hyperacusis; we just recently discovered “Acoustic Shock Disorder” as the most likely diagnosis. Now it’s just a question of treatment. Meds CAN help, but the most effective therapy is noise tolerance training, in which one is subjected to progressive levels of white and pink noise in order to build up a tolerance and retrain the body to more appropriately interpret
    sound stimuli.
    This condition is considered as “rare” as myoclonus…I doubt it actually is. The worst part, though, is that without the muscle jerks, only those who are aware of the problem AND paying attention even notice the problem. Visiting friends with children and/or dogs is often disabling, especially if their children’s “playful shrieking” goes unchecked; just a high-pitched laugh can do it. I normally try to draw attention to it by asking if he’s okay…sometimes it helps, sometimes not. Needless to say, we stay in most of the time.
    Matt, I have scoured your blog and it was SO helpful, but it was your description that confirmed in our minds that hyperacusis was the more appropriate diagnosis, and wanted to make sure others out there were aware of another possibility,if myoclonus didn’t sound quite right. Hope this helps!

    See hyperacusis.net for more information.

  • Matt Allen G author
    5 years ago

    Jules, YES, I should have mentioned this in the article as RIGHT BEFORE I learned about myoclonus I was sure it was hyperacousis and was asking my physical therapist about TRT (Tinnitus Retraining Therapy – The white noise thing you mentioned). Turns out I did not have Hyperacousis but myoclonus which has a lot of the same characteristics which is why there are so easily confused.Thanks for reminding me about this and what it’s called; hopefully it will help someone find an answer!

  • Alysongayle
    5 years ago

    This particular symptom has affected me tremendously in the social aspect. For many years I could not have been more frightened to be around anybody doing anything because they feared that I would have uncontrollable muscle spasm. The reaction I got were not totally bizarre, however I noticed that it was not just me who was disturbed by my symptom yet most if not all people tend to feel very uncomfortable around me because most people Think that they are causing me to be scared. I know I speak extremely soft in which many respond to me asking very loudly, “what?” Or “Speak up”! Once I noticed that when there Tone would raise and in turn I jump it would almost be frightening to others I became so self conscious that I would always be waiting for the next sound.
    I can not thank you enough for writing about this because, like many I never connected this with being a symptom of MS and I never told my Neurologist that this was a frequent experience of mine.
    Thank you again for sharing your story Matt.

  • Matt Allen G author
    5 years ago

    I just knew it had to be something because I used to be the guy in the theatre who didn’t so much as blink when something made everyone else kump. Made no sense and it was making life horrible so I had to find out what it was :p

  • Pattycake
    5 years ago

    Matt, thanks so much for exploring and investigating this subject so fully. I truly thought this was something that was just some sort of personal defect.
    I appreciate it!

  • Matt Allen G author
    5 years ago

    Most people do but a lot of the time it can be linked to MS. Not always of course but a lot of the time!+

  • Lefty Lib
    5 years ago

    I am pleasantly surprised to see how much time you devoted to your question about this most annoying symptom many of us MSers experience. I had the same question you did, and some time ago presented it to others on a MS forum asking if they, too, had problems with being startling by loud sounds or surprise appearances. Several people responded with the same issue and one expressed thanks she wasn’t going crazy – she thought she was the only one! I asked my neurologist and she assumed, like me, that because I already deal with other sensory issues, it made sense to think my startle reflex was due to that sensitivity. I never sought out a real solution like you did, assuming there wasn’t much I could do, and she didn’t offer one. I’m glad you found yours, however, and that it’s working well. I am not willing to subject my system to any more meds that aren’t completely necessary at this point in my life, so will continue on with the “jumping” and calming down routine for now. Klonopin I used one time while coming down off steroids, but seemed too strong to use regularly. And, in all honesty, I use medical MJ in the evenings to sooth my anxiety and pain, and it may well also guard against the jumpiness, but I’ve never put it to a real test. For those not having success with current treatments, may I suggest you look into CBDs (cannabidiols without the psychoactive effect of THC). http://hempmeds.com

  • Pattycake
    5 years ago

    Lefty Lib, I have looked into buying some sort of CBD oil, would love to try it, but I am VERY leery of ingesting an unregulated product from an online source. How do I know I’m purchasing what they say I am?
    Thanks!

  • Matt Allen G author
    5 years ago

    its sad that so my neurologists don’t have a clue what this is and how easy it is to solve. Klonopin doesn’t effect me negatively at all. I cant tell when I take it but I can tell when I DON’T take it. So honestly I am fine with my current regimen and don’t feel is necessary to try something new.

  • But You Look So Well
    5 years ago

    I have to say, I’ve had MS since 1978, and I’ve tried lots of online support communities, but multiplesclerosis.net is the BEST! I have myoclonus too! I drop things, spill herbal tea all over the place, break plates, etc. I must admit it’s not nearly as severe as Matt’s case, and I don’t think I need medication for it, but you really hit the nail on the head when you described the symptom. I placed my first order with Replacements.com, a well known online source for replacing parts of your china or silverware set that have succumbed to my case of the dropsies. Matt, thank you so much for describing this symptom! I’ve had it as long as I’ve had MS (i’m secondary progressive, but doing extremely well with copaxone and TONS of physical therapy. And I recently saw a remark about having trouble with sleep as an MS symptom. I’m going to go comment on that one too. I love you guys! Many thanks, and keep on keepin on.

  • Matt Allen G author
    5 years ago

    Glad you like it here! Many different walk of life. But hey, do you drop things because of “clumsiness” or because you jump? I ask because clumsiness is something different. I have BOTH but Myoclonus is way worse for me!

  • Dianna lyn
    5 years ago

    If this is so rare, then why do I seem to have similar symptoms with my ms?? Maybe, because neurologist out there excuse it as being normal??..comes with age they tell me? Hmm?? I wonder??

  • Lefty Lib
    5 years ago

    I think the point is that it isn’t all that rare. And once mentioned, you’ll find a number of others admitting to it. I think many of us have done some type of research… I just started out by looking up “startle effect” and then paired it with MS. I am always relieved to find others reaching similar conclusions and then having it confirmed (and treated!). Thank you Matt Allen G!

  • Matt Allen G author
    5 years ago

    Sometimes I think it’s not as rare as they make it out to be, just another undiagnosed symptom that most people just accept without question… It’s hard to know as no one really talks about it because they don’t realize it’s something worth talking about!

  • Maria Jablonski
    5 years ago

    Klonopin does not work for me. Lucky for you it seems to be your “miracle” pill. I take Nucynta at night and it helps but the side effects are very unpleasant. It’s a very strong narcotic for pain. It takes away the “jerky” movement but it makes me incredibly anxious. I have not found anything else to remotely make the myoclonus better. I have high hopes for the future of medicine because I can not fathom anyone living like this for the test of their lives.

  • Matt Allen G author
    5 years ago

    I couldn’t either. There were days I wanted to scoop out my ear drumbs with a spoon! Have you tried any other Benzo’s? Not sure if they would all work but who knows? Now I am curious…

  • Laura Kolaczkowski
    5 years ago

    If I understand it correctly, Hyperekplexia is fairly rare and almost always starts as a disorder as an infant. thanks for doing the research and working to get the correct information out there.

  • Matt Allen G author
    5 years ago

    without any medical training/degree I would say there is no late onset that I have heard of. It’s hereditary and affects infants who (I believe) are under the age of two. I feel like if I saw a group of people following some “leader” down a path of “doom” I should PROBABLY warn them you know haha? Long day, can’t come up with better analogies right now… :p

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