This is a glossary of medical terms related to communication disorders which are psychological or medical conditions that could have the potential to affect the ways in which individuals can hear, listen, understand, speak and respond to others.
A spasm is a sudden involuntary contraction of a muscle, a group of muscles, or a hollow organ, such as the bladder.
Myoclonus is a brief, involuntary, irregular twitching of a muscle, a joint, or a group of muscles, different from clonus, which is rhythmic or regular. Myoclonus describes a medical sign and, generally, is not a diagnosis of a disease. It belongs to the hyperkinetic movement disorders, among tremor and chorea for example. These myoclonic twitches, jerks, or seizures are usually caused by sudden muscle contractions or brief lapses of contraction. The most common circumstance under which they occur is while falling asleep. Myoclonic jerks occur in healthy people 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.
Writer's cramp or focal hand dystonia (FHD) is an idiopathic movement disorder of adult onset, characterized by abnormal posturing and movement of the hand and/or forearm during tasks requiring skilled hand use, such as writing. Overcontraction of affected muscles, cocontraction of agonist and antagonist pairs, and activation of muscles inappropriate to a task all impair use of the affected hand.
Dystonia is a neurological hyperkinetic movement disorder in which sustained or repetitive muscle contractions occur involuntarily, resulting in twisting and repetitive movements or abnormal fixed postures. The movements may resemble a tremor. Dystonia is often intensified or exacerbated by physical activity, and symptoms may progress into adjacent muscles.
Dyskinesia refers to a category of movement disorders that are characterized by involuntary muscle movements, including movements similar to tics or chorea and diminished voluntary movements. Dyskinesia can be anything from a slight tremor of the hands to an uncontrollable movement of the upper body or lower extremities. Discoordination can also occur internally especially with the respiratory muscles and it often goes unrecognized. Dyskinesia is a symptom of several medical disorders that are distinguished by their underlying causes.
Hyperkinesia refers to an increase in muscular activity that can result in excessive abnormal movements, excessive normal movements, or a combination of both. Hyperkinesia is a state of excessive restlessness which is featured in a large variety of disorders that affect the ability to control motor movement, such as Huntington's disease. It is the opposite of hypokinesia, which refers to decreased bodily movement, as commonly manifested in Parkinson's disease.
Palatal myoclonus is a rare condition in which there are rhythmic jerky movements or a rapid spasm of the palatal muscles. Chronic clonus is often due to lesions of the central tegmental tract.
Focal dystonia, also called focal task-specific dystonia, is a neurological condition that affects a muscle or group of muscles in a specific part of the body during specific activities, causing involuntary muscular contractions (spasms) and abnormal postures. There are many different types of focal dystonia, each affecting a different region of the body. For example, in focal hand dystonia, or writer's cramp, the fingers either curl into the palm or extend outward without control. In musicians, the condition is called musician's focal dystonia, or simply, musician's dystonia. In sports, it may be involved in what is commonly referred to as the yips. The condition appears to be associated with over-training, and individualized treatment strategies may involve medications, retraining techniques, and procedures.
A fasciculation, or muscle twitch, is a spontaneous, involuntary muscle contraction and relaxation, involving fine muscle fibers. They are common, with as many as 70% of people experiencing them. They can be benign, or associated with more serious conditions. When no cause or pathology is identified, they are diagnosed as benign fasciculation syndrome.
Torsion dystonia, also known as dystonia musculorum deformans, is a disease characterized by painful muscle contractions resulting in uncontrollable distortions. This specific type of dystonia is frequently found in children, with symptoms starting around the ages of 11 or 12. It commonly begins with contractions in one general area such as an arm or a leg that continue to progress throughout the rest of the body. It takes roughly 5 years for the symptoms to completely progress to a debilitating state.
Blepharospasm is a neurological disorder characterized by intermittent, involuntary spasms and contractions of the orbicularis oculi (eyelid) muscles around both eyes. These result in abnormal twitching or blinking, and in the extreme, sustained eyelid closure resulting in functional blindness.
Spasmodic torticollis is an extremely painful chronic neurological movement disorder causing the neck to involuntarily turn to the left, right, upwards, and/or downwards. The condition is also referred to as "cervical dystonia". Both agonist and antagonist muscles contract simultaneously during dystonic movement. Causes of the disorder are predominantly idiopathic. A small number of patients develop the disorder as a result of another disorder or disease. Most patients first experience symptoms midlife. The most common treatment for spasmodic torticollis is the use of botulinum toxin type A.
Propantheline bromide (INN) is an antimuscarinic medication used for the treatment of excessive sweating (hyperhidrosis), cramps or spasms of the stomach, intestines (gut), or bladder, and involuntary urination (enuresis). It can also be used to control the symptoms of irritable bowel syndrome (IBS) and similar conditions. This medication can also be used for patients who experience intense gastrointestinal symptoms while tapering off of tricyclic antidepressants.
Myokymia is an involuntary, spontaneous, localized quivering of a few muscles, or bundles within a muscle, but which are insufficient to move a joint. One type is superior oblique myokymia.
Synkinesis is a neurological symptom in which a voluntary muscle movement causes the simultaneous involuntary contraction of other muscles. An example might be smiling inducing an involuntary contraction of the eye muscles, causing a person to squint when smiling. Facial and extraocular muscles are affected most often; in rare cases, a person's hands might perform mirror movements.
Pleurothotonus, commonly known as Pisa syndrome, is a rare neurological disorder which occurs due to prolonged exposure to antipsychotic drugs. It is characterized by dystonia, and abnormal and sustained involuntary muscle contraction. This may cause twisting or jerking movements of the body or a body part. Although Pisa syndrome develops most commonly in those undergoing long-term treatment with antipsychotics, it has been reported less frequently in patients receiving other medications, such as an acetylcholinesterase inhibitor. However, it has also been seen in those with other diseases causing neurodegeneration and in those who are not receiving any medication. The characteristic development of Pisa syndrome consists of two types of dystonia: acute dystonia and tardive dystonia. The underlying pathology of drug-induced Pisa syndrome is very complex, and development may be due to an underlying dopaminergic-cholinergic imbalance, or serotonergic/noradrenergic dysfunction.
Oromandibular dystonia(OMD) is an uncommon focal neurological condition affecting the jaws, face, and mouth. Oromandibular dystonia is characterized by involuntary spasms of the tongue, jaw, and mouth muscles that result in bruxism, or grinding of the teeth, and jaw closure. These conditions frequently lead to secondary dental wear as well as temporomandibular joint syndrome. In addition, problems with chewing, speaking, and swallowing may result from jaw opening, involuntary tongue movements, or jaw deviation.
In ophthalmology, apraxia of lid opening (ALO) is an inability to initiate voluntary opening of the eyelid following a period of eyelid closure, with normal function at other times. Manual lifting of the eyelid often resolves the problem and the lid is able to stay open.
Alan Brown Scott was an American ophthalmologist specializing in eye muscles and their disorders, such as strabismus. He is best known for his work in developing and manufacturing the drug that became known as Botox, research described as "groundbreaking" by the ASCRS.
