the pyramidal cells in layer 5 of areas 4, 6 ,3-1&2
the corticospinal tract and the pyramidal spinal tract are the same tract. yes this tract is the main voluntary motor tract, remember that this tract split in two after the decussation of pyramids (hence the term pyramidal tract) the fibres that do decussate create the lateral portion which innervates the limbs, shoulders and neck the fibers that dont decussate here continue ipsilaterally creating an anterior/ventral portion which innervate the truck, these eventually do decussate at their spinal exit level
It arises as the axons of the giant pyramidal cells of Betz mainly from the upper 2/3of the motor area 4 in the precentral gyrus.
The pyramidal tract crosses at the medulla oblongata in a region known as the pyramidal decussation. This is where most of the motor fibers originating from the cortex cross to the opposite side of the brain to control movement on the contralateral side of the body.
Lateral corticospinal tract is the part of pyramidal tract that consists of crossed pyramidal fibres. So, it's also called as "crossed pyramidal tract".as for anterior corticospinal tract, it consists of uncrossed pyramidal fibres.
Disorders of the pyramidal tracts are characterized by spasticity and paralysis (e.g., stroke). The pyramidal motor system originating in the motor cortex provides control of delicate muscle movement. Tracts of the pyramidal motor system are the corticospinal tract, cortibulbar tract, coricopontine. It is often difficult to delineate a pyramidal from an extrapyramidal lesion during a clinical assessment. Good link for explanation: http://books.google.com/books?id=yY5scDAv8oUC&pg=PA60&lpg=PA60&dq=assess+pyramidal+motor+system+lesion&source=bl&ots=UyFuRjg71r&sig=xj0Gq91LYkRlVCZdra6mH6LTCPo&hl=en&ei=84LyScjSOpOwMfbP_MIP&sa=X&oi=book_result&ct=result&resnum=1#PPA67,M1
Chris Theodorakis had pyramidal tract involvement. I am just now reading The Westing Game myself for a book report/project and so far this is the most interresting books i have ever read.
Rubrospinal tractTectospinal tractLateral reticulospinal tract
Vestibulspinal tract (majority of its fibres are uncrossed)Olivospinal tractMedial Reticulospinal tract*mnemonic to memorize: V-O-MER
The "internal pyramidal layer" is the 5th layer of neocortex. You can find lots of large pyramidal neurons at this layer and they project their axons to subcortical structure.You can also find the "giant pyramidal cells of Betz" at this 5th layer of the motor areas. They are very large and they send their axons to corticospinal tract.
Ziggurats were temples of Sumerian origin in the form of pyramidal towers, consisting of a number of levels.
pyramidal
A positive finding in an adult could suggest signs of hyperreflexia, spasticity, and a positive Babinski sign. These are commonly seen in upper motor neuron lesions affecting the pyramidal tract. Further evaluation and testing may be needed to confirm the diagnosis.