rubrospinal การใช้

• It is hypothesized that it uses both the corticospinal tract and rubrospinal tract.
• These are the rubrospinal tract, the vestibulospinal tract, the tectospinal tract and the reticulospinal tract.
• The rubrospinal tract descends with the lateral corticospinal tract, and the remaining three descend with the anterior corticospinal tract.
• However, where the corticospinal tract is dominant ( as in primates ), the rubrospinal tract may be considered to be vestigial.
• The netrin is expressed by neurons in the corticospinal and rubrospinal projections, and by intrinsic neurons of the spinal cord both before and after the injury.
• He name is lent to " Monakow's nucleus " ( lateral cuneate nucleus ) and to the " bundle of Monakow " ( rubrospinal fasciculus ).
• Upper motor neurons ( UMNs ) send input to ?-MNs via several pathways, including ( but not limited to ) the corticospinal, and rubrospinal tracts.
• In some other primates, however, experiments have shown that over time, the rubrospinal tract can assume almost all the duties of the corticospinal tract when the corticospinal tract is lesioned.
• The effects on these two tracts ( corticospinal and rubrospinal ) by lesions above the red nucleus is what leads to the characteristic flexion posturing of the upper extremities and extensor posturing of the lower extremities.
• While decorticate posturing is still an ominous sign of severe brain damage, decerebrate posturing is usually indicative of more severe damage at the rubrospinal tract, and hence, the red nucleus is also involved, indicating a lesion lower in the brainstem.
• The descending rubrospinal tract and reticulospinal tract originate in the red nucleus and reticular formation ( which is closely associated with the central tegmental tract ) respectively, thereby providing the mechanism by which this circuit exerts its effects on spinal cord motor activity.