extrapyramidal
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extrapyramidal
[eks″trah-pĭ-ram´ĭ-d'l]outside the pyramidal tracts.
extrapyramidal disease (extrapyramidal syndrome) any of a group of clinical disorders marked by abnormal involuntary movements, alterations in muscle tone, and postural disturbances; the group includes parkinsonism, chorea, athetosis, and others.
extrapyramidal system a functional, rather than anatomical, unit comprising the nuclei and fibers (excluding those of the pyramidal tract) involved in motor activities; they control and coordinate especially the postural, static, supporting, and locomotor mechanisms. It includes the corpus striatum, subthalamic nucleus, substantia nigra, and red nucleus, along with their interconnections with the reticular formation, cerebellum, and cerebrum; some authorities include the cerebellum and vestibular nuclei. Called also extrapyramidal tract.
ex·tra·py·ram·i·dal
(eks'tră-pi-ram'i-dăl),Other than the pyramidal tract. See: extrapyramidal motor system.
extrapyramidal
/ex·tra·py·ram·i·dal/ (-pĭ-ram´ĭ-d'l) outside the pyramidal tracts; see under system.extrapyramidal
(ĕk′strə-pĭ-răm′ĭ-dl)adj.
Relating to or involving neural pathways situated outside or independent of the pyramidal tracts.
extrapyramidal
[ek′strəpiram′ədəl]
Etymology: L, extra + Gk, pyramis, pyramid
1 pertaining to the tissues and structures outside the cerebrospinal pyramidal tracts of the brain that are associated with movement of the body, excluding motor neurons, the motor cortex, and the corticospinal and corticobulbar tracts.
2 pertaining to the function of these tissues and structures.
extrapyramidal
adjective Referring to that which occurs outside of the pyramidal system of the brain.ex·tra·py·ram·i·dal
(eks'tră-pir-am'i-dăl)Outside or not involving the pyramidal tract of the central nervous system.
extrapyramidal
outside the pyramidal tracts.
extrapyramidal disease, extrapyramidal syndrome
any of a group of clinical disorders marked by abnormal involuntary movements, alterations in muscle tone, and postural disturbances.
extrapyramidal motor system
see extrapyramidal system (below).
extrapyramidal system
a functional, rather than anatomical, unit comprising the nuclei and fibers (excluding those of the pyramidal tract) involved in motor activities; they control and coordinate especially the postural, static, supporting and locomotor mechanisms. It includes the corpus striatum, subthalamic nucleus, substantia nigra and red nucleus, along with their interconnections with the reticular formation, cerebellum and cerebrum; some authorities include the cerebellum and vestibular nuclei. Called also extrapyramidal motor system.