Lab 9 Upper Lower Motor Systems 1 SMA

Lab 9 Upper & Lower Motor Systems

1 SMA Motor planning FEF PMA Motor planning Of voluntary action Prefrontal Cortex • Processing sensory and memory info • Decision making What is the ~location of the: Prefrontal Cortex? PMA (premotor area)? SMA (supplementary motor area) FEF (frontal eye field)

1 2

1 2 3

1 Thalamus 2 3 4

1 Thalamus 2 3 Lentiform Nucleus

1 2 Putamen 3 (lentiform nucleus)

ant. limb, Int. capsule (frontal eye field fibers) 1 head of caudate nucleus 2 frontal horn, lateral ventricle 3 optic chiasm 4 putamen ICA

Post. limb, int. capsule: corticospinal + corticopontine 2 + thalamocortical fibers Body 3 of lateral ventricle thalamus 4 descending cortical 1 fibers in crus cerebri of midbrain 5 Ventricle III Lentiform nucleus 6 putamen is visible) (only

What descending fibers from the primary motor cortex have degenerated in the indicated areas?

Abbreviations: CS = corticospinal CB = corticobulbar 2 CB Position of: oculomotor 3 nucleus + nerve roots 4 1 CS optic tract CB 6 CS 7 Oculomotor nerve roots 8 RED 5 NUCLEUS Red nucleus 10 Midbrain/Thalamic Junction Oculomotor nucleus 9

descending 1 fibers cortical 2 MLF Trochlear nucleus 3 Caudal Midbrain

reticular formation with descending rubrospinal descending cortical fibers trigeminal nerve motor nuc. & nerve roots of V 3 2 4 5 descending cortical fibers 7 6 Nerve Roots of V 1 motor nucleus of V 8 Mid Pons

Reticular formation with reticular nuclei & descending rubrospinal fibers 5 descending cortical fibers 3 abducens nerve roots 4 8 descending 9 fibers nucleus cortical fibers facial nucleus exit of facial 7 nerve roots facial nucleus 2 Facial nerve roots 1 abducens exit of VI nerve nucleus roots 10 nucleus abducens nucleus 6 Caudal Pons 11 nerve

Hypoglossal 2 nerve roots Pyramidal 3 (corticospinal) tract reticular formation with reticular nuclei + & descending rubrospinal & reticulospinal fibers 4 8 pyramidal tract Vagal 1 Nerve nerve roots nuc. ambiguus 9 11 Hypoglossal nuc. Vest. 10 Nuc. vestibular 5 nuclei nucleus hypoglossal 6 7 ambiguus nucleus Rostral Medulla

Pyramidal decussation 1 crossing general position of 2 crossing pyramidal decussation Caudal Medulla

Position of: ventral horn corticospinal, vestibulospinal, with LMN & reticulospinal tracts lateral corticospinal tract medial & lateral & rubrospinal tracts ventral corticospinal, vestibulo+ rubrospinal tract motor nuclei in spinal, & reticulospinal tracts 5 2 4 1 6 3 ventral horn . . Cervical Spinal Cord

Co rtic Fib osp er ina l s Corticobulbar fibers – go to genu of internal capsule What is the ~location of the: Corticospinal Fibers? Corticobulbar Fibers? Rostral Midbrain Level

Red Nucleus C or tic Fi os be pi rs na l Corticobulbar fibers What is the ~location of the: Corticobulbar Fibers? Corticospinal Fibers? Red Nucleus? Oculomotor Nucleus & Nerve? Occulomotor Nucleus Nerve Rostral Midbrain Level

Trochlear Nucleus – fibers from FEF via Premotor Area al n i sp s o tic iber r Co F ar lb u ob s tic ber r i Co f What is the ~location of the: Corticobulbar Fibers? Corticospinal Fibers? Trochlear Nucleus? Caudal Midbrain Level

Trochlear nerve exit PAG Corticospinal and corticobulbar fibers mixed What is the ~location of the: Corticobulbar & Corticospinal Fibers? PAG? Trochlear Nerve? Rostral Pons Level

Trigeminal Main Motor Nucleus Supplies muscles of mastication Reticular Formation Corticospinal and corticobulbar fibers mixed What is the ~location of the: Corticobulbar & Corticospinal Fibers? Trigeminal Motor Nucleus? Reticular Formation? Rostral Pons Level

Abducens Nucleus Facial Nerve Fibers Reticular Formation Corticospinal and corticobulbar fibers mixed What is the ~location of the: Corticobulbar & Corticospinal Fibers? Facial Nerve Fibers? Abducens Nucleus? Reticular Formation? Rostral Medulla Level

Hypoglossal Nerve Roots & Nucleus Vestibular Nuclei MLF Reticular Formation Pyramid What is the ~location of the: Pyramid? MLF? Vestibular Nuclei? Reticular Formation? Hypoglossal Nucleus & Nerve Roots? Rostral Medulla Level

Lateral Corticospinal tract Rubrospinal Tract Lateral Motor nuclei What is the ~location of the: Lateral Corticospinal Tract? Medial Motor nuclei Lateral Vestibulospinal tract Rubrospinal Tract? Lateral Motor Nuclei Lateral Vestibulospinal Tract? Medial Motor Nuclei Lumbar Level

Lateral Corticospinal tract Rubrospinal Tract Anterior Corticospinal tract Medial Motor nuclei What is the ~location of the: Lateral Corticospinal Tract? Rubrospinal Tract? Medial Motor Nuclei Anterior Corticospinal Tract? Thoracic Level

Lateral Corticospinal tract Rubrospinal Tract What is the ~location of the: Lateral Corticospinal Tract? Rubrospinal Tract? C 7 Level