action tremor


Also found in: Dictionary, Thesaurus, Encyclopedia.

tremor

 [trem´or, tre´mor]
an involuntary trembling of the body or limbs; it may have either a physical or a psychological cause. Early symptoms include trembling of the hands and nodding of the head. Tremors are often associated with parkinson's disease, which affects nerve centers in the brain that control the muscles. They also occur in cerebral palsy, hyperthyroidism, and withdrawal from narcotics or alcohol. They tend to develop as one of the results of aging, and are sometimes symptoms of temporary abnormal conditions such as insulin shock, or of poisoning, especially metallic poisoning. They sometimes appear with a high fever resulting from an infection. Tremors of psychological origin take many forms, some minor and some serious. Violent, uncontrollable trembling is often seen in certain phases of severe mental disorders. If there is no physiological cause, they may be a sign of general tension.
action tremor rhythmic, oscillatory movements of the outstretched upper limb when voluntary movements are attempted, as when writing or lifting a cup; it may also affect the voice and other parts. Called also intention tremor and volitional tremor.
coarse tremor that involving large groups of muscle fibers contracting slowly.
essential tremor a hereditary tremor with onset at varying ages, usually at about 50 years of age, beginning with a fine rapid tremor (as distinct from that of parkinsonism) of the hands, followed by tremor of the head, tongue, limbs, and trunk; it is aggravated by emotional factors, is accentuated by volitional movement, and in some cases is temporarily improved by alcohol.
fine tremor one in which the vibrations are rapid.
flapping tremor asterixis.
intention tremor action tremor.
parkinsonian tremor a type of resting tremor commonly seen with parkinsonism, consisting of slow, regular movements of the hands and sometimes the legs, neck, face, or jaw; it typically stops upon voluntary movement of the part and is intensified by stimuli such as cold, fatigue, and strong emotions.
physiologic tremor a rapid transient tremor of extremely low amplitude found in the limbs and sometimes the neck or face of normal individuals, only subtly detectable on an electromyogram and seldom visible to the naked eye; it may become accentuated and visible under certain conditions.
rest tremor (resting tremor) one occurring in a relaxed and supported limb, such as a parkinsonian tremor.
senile tremor one due to the infirmities of old age.
volitional tremor action tremor.

in·ten·tion trem·or

a tremor that occurs during the performance of precise voluntary movements, caused by disorders of the cerebellum or its connections.

action tremor

Etymology: L, agere, to do, tremor, shaking
a slight shaking that occurs or is evident during voluntary movements of the upper extremities. Also called intention tremor. See also resting tremor.

action tremor

A tremor that occurs during any type of movement of an affected body part. 

Types
• Postural tremor—Occurs when maintaining a position against gravity—e.g., holding arms outstretched. 
• Kinetic tremor—Appears during movement of a body part, such as moving the wrists up and down.
• Intention tremor—Present during a purposeful movement toward a target, such as touching a finger to one’s nose during a medical exam. 
Task-specific tremor—Appears when performing highly skilled, goal-oriented tasks, such as handwriting or speaking. 
Isometric tremor—Occurs during a voluntary muscle contraction that is not accompanied by any movement.

in·ten·tion trem·or

(in-ten'shŭn trem'ŏr)
A tremor that occurs during the performance of precise voluntary movements, caused by disorders of the cerebellum or its connections.
Synonym(s): volitional tremor (2) .

in·ten·tion trem·or

(in-ten'shŭn trem'ŏr)
Tremor that occurs during performance of precise voluntary movements, caused by disorders of cerebellum or connections.
Synonym(s): action tremor.

tremor

a continuous repetitive twitching of skeletal muscle, usually palpable and visible. The diseases characterized by tremor only, the tremor syndromes, may be caused by degenerative disease of the nervous system, e.g. hypomyelinogenesis, and by many toxins, especially plant ones. Tremor is also a sign in many other diseases of the nervous system.

action tremor
rhythmic, oscillatory, involuntary movements of the limbs.
coarse tremor
that involving large groups of muscle fibers contracting slowly.
congenital tremor syndrome of piglets
epidemic tremor
fibrillary tremor
rapidly alternating contraction of small bundles of muscle fibers.
fine tremor
one in which the vibrations are rapid.
intention tremor
one occurring when voluntary movement is attempted. See also volitional tremor (below).
rest tremor
tremor occurring in a relaxed and supported limb.
tremor syndrome
see shaker dogs. Called also white dog shaker syndrome.
volitional tremor
trembling of the entire body during voluntary effort.
References in periodicals archive ?
Diagnoses of ET were not assigned in NAS; however, it was possible to assess action tremor because participants produced drawings as part of cognitive tests that required them to copy different figures.
In conclusion, the evidence presented suggests that the VIM DBS is an important site for reducing action tremor and improving force control in PD.
Lead is a ubiquitous toxicant (Konat and Clausen 1974; Schroeder and Tipton 1968), and laboratory animals and humans exposed to high levels of either inorganic or organic forms of lead develop neurologic disorders in which action tremor is prominent (Booze et al.
Postural and action tremors (tremors that occur during movement) are caused by multiple health problems.
Tremors are classified as rest or action tremors, with the latter being further categorized as postural (occurring while the patient maintains a position against gravity) or kinetic (occurring during voluntary movement).