Last Reviewed : 12/24/2020

Myoclonus is a brief, involuntary twitching of a muscle or a group of muscles. It describes a medical sign and, generally, is not a diagnosis of a disease. These myoclonic twitches, jerks, or seizures are usually caused by sudden muscle contractions (positive myoclonus) or brief lapses of contraction (negative myoclonus). The most common circumstance under which they occur is while falling asleep (hypnic jerk). Myoclonic jerks occur in healthy persons and are experienced occasionally by everyone. However, when they appear with more persistence and become more widespread they can be a sign of various neurological disorders. Hiccups are a kind of myoclonic jerk specifically affecting the diaphragm. When a spasm is caused by another person it is known as a provoked spasm. Shuddering attacks in babies fall in this category.

Myoclonic jerks may occur alone or in sequence, in a pattern or without pattern. They may occur infrequently or many times each minute. Most often, myoclonus is one of several signs in a wide variety of nervous system disorders such as multiple sclerosis, Parkinson's disease, Dystonia, Alzheimer's disease, Gaucher's Disease, subacute sclerosing panencephalitis,Creutzfeldt–Jakob disease (CJD), serotonin toxicity, some cases of Huntington's disease, some forms of epilepsy, and occasionally in intracranial hypotension. Some researchers indicate that jerks persistently may even cause early tremors.

In almost all instances in which myoclonus is caused by central nervous system disease it is preceded by other symptoms; for instance, in CJD it is generally a late-stage clinical feature that appears after the patient has already started to exhibit gross neurological deficits.

Anatomically, myoclonus may originate from lesions of the cortex, subcortex or spinal cord. The presence of myoclonus above the foramen magnum effectively excludes spinal myoclonus; further localisation relies on further investigation with electromyography (EMG) and electroencephalography.

We researched this topic for you and found the following best online resources. They are categorized into basic, advanced, and research level based on the extent of information you need. You will be taken to the respective websites by pressing on the links below.


Basic information: national institute of neurological disorders and stroke myoclonus mayo clinic myoclonus merck manuals (professional version) myoclonus msd manuals (professional version) myoclonus cleveland clinic myoclonus sleep association sleep myoclonus web md progressive myoclonus epilepsy myoclonus about kids health myoclonus john hopkins medical library myoclonus inner body myoclonus


Advanced information: medscape benign neonatal sleep myoclonus national organisation for rare diseases myoclonus med link myoclonus life in the fast lane post-hypoxic myoclonus (phm) family practise notebook myoclonus



sharma cm, nath k, kumawat bl, khandelwal d. autosomal dominant cortical tremor, myoclonus, and epilepsy (adcme): probable first family from india. ann indian acad neurol [serial online] 2014 [cited 2016 oct 11];17:433-6. available from: s. laroumagne, xavier elharrar, b. coiffard, et al., ““dancing eye syndrome” secondary to opsoclonus-myoclonus syndrome in small-cell lung cancer,” case reports in medicine, vol. 2014, article id 545490, 4 pages, 2014. doi:10.1155/2014/545490

abiramalatha t, mehndiratta s, rajeshwari k, dubey ap. piperazine citrate induced myoclonus in a child. indian j pharmacol [serial online] 2013 [cited 2016 oct 11];45:640. available from: davis manuel, c. b. rathore, alie alexander. “clinical, neuropsychological and neurophysiological correlates of drug resistant juvenile myoclonic epilepsy”. journal of evidence based medicine and healthcare; volume 2, issue 36, september 07, 2015; page: 5658-5668, doi: 10.18410/jebmh/2015/780

sharma cm, pandey rk, kumawat bl, khandelwal d. late-onset myoclonic epilepsy in down syndrome (lomeds): a spectrum of progressive myoclonic epilepsy — case report. ann indian acad neurol [serial online] 2016 [cited 2016 oct 11];19:267-8. available from: original research article front. neurol., 20 february 2012 | deep brain stimulation of the pallidum is effective and might stabilize striatal d2receptor binding in myoclonus–dystonia by r. j. beukers et al.,

park js, park sp, seo jg. hirayama disease with juvenile myoclonic epilepsy: a case report. ann indian acad neurol [serial online] 2014 [cited 2016 oct 11];17:358-60. available from: central neuraxial anaesthesia presenting with spinal myoclonus in the perioperative period: a case series by olumuyiwa a bamgbade et al., journal of medical case reports20093:7293 doi: 10.4076/1752-1947-3-7293

jain p, sharma s, van ruissen f, aneja s. myoclonus-dystonia: an under-recognized entity - report of 5 cases. neurol india [serial online] 2016 [cited 2016 oct 11];64:980-3. available from: sofie n. de blauwe, patrick santens, and ludo j. vanopdenbosch, “anti-glycine receptor antibody mediated progressive encephalomyelitis with rigidity and myoclonus associated with breast cancer,” case reports in neurological medicine, vol. 2013, article id 589154, 4 pages, 2013. doi:10.1155/2013/589154


Other articles: pet md muscle contraction disease (myoclonus) in dogs vetary muscle contraction disease (myoclonus) in dogs

read more at:


Other helpful resources(support groups): study finds high levels of misdiagnosis in juvenile myoclonic epilepsy


Related videos: myoclonus myoclonus myoclonic jerking myoclonic epilepsy - sleep myoclonus


Presentations/quiz/newspaper articles: myoclonus dr ps deb md, dm director neurology gnrc hospitals , guwahati, assam, india

Please leave your comments:

Related Articles