INTEGBI 131 Lecture Notes - Lecture 8: Vestibulospinal Tract, Dorsal Root Ganglion, Reticular Formation
6 Jan 2020
School
Department
Course
Professor
Chapter 13a: CNS
(spinal cord, brain stem, [prosen]diencephalon, cerebellum)
CNS (rOstral —> nOse; cAudal —> tAil)
- Spinal Cord: w/nerves for sensory & motor innervation (signals between body & brain),
center for reflexes
- Location: through vertebral canal (of foramina) // ^ foramen magnum (skull) —>
L3 infants & L1 or 2 in children & adults v
- Conus medullaris (inferior end of spinal cord)
- Filum terminale (long/central filament of CT from conus —> coccyx;
anchors spinal cord)
- Cadua equina (spinal nerve roots @end of vertebral canal / “horse tail”)
- Cervical & lumbar enlargements: nerves for limbs arise here
- CROSS SECTION
- Grooves divide into L/R:
- dorsal (posterior) median sulcus- gray wings touch edge
- ventral (anterior) median fissure- wider & deeper
- White matter: outer region w/myelinated & unmyel. axons; allows
communication between spinal cord & brain
- w/funiculi (“long ropes”)
- Dorsal (posterior), Ventral (anterior), & Lateral funiculus
- w/fibers
- Ascending: carry sensory info from neurons —> brain
- Descending: carry motor info from brain —> spinal cord
—>action
- Commissural: carry info from side —> side of spinal cord
- Commissure: bundle of axons that cross from side
—> side of CNS
-Gray matter: inner “butterfly” & cross-bar has unmyelinated axons &
central cavity
- Dorsal (w/interneurons
that receive info from sensory neurons),
ventral, & lateral (only Thoracic & Lumbar segments of spinal
cord) horns
- Dorsal root ganglia pl.(bulb): w/sensory neuron cell bodies
- Dorsal roots (fibers): connect spinal cord to sensory neuron axons
- “Ventral & lateral horns of gray matter in spinal cords”
- w/cell bodies
of motor & interneurons
-[Motor neurons] axons from spinal cord —> Ventral roots —>
muscle & glands
- Ventral horns largest in C & L enlargements (innervate limbs here)
- Dorsal (posterior): somatic & visceral Sensory (SS, VS)
- Ventral (anterior): somatic & visceral autonomic Motor (SM, VM)
- Paresthesia: (lose sensory function) damage to DORSAL horn or sensory
neuron cell bodies in dorsal root ganglia
Document Summary
Chapter 13a: cns (spinal cord, brain stem, [prosen]diencephalon, cerebellum) Cns (rostral > nose; caudal > tail) center for reflexes. Spinal cord: w/nerves for sensory & motor innervation (signals between body & brain), Location: through vertebral canal (of foramina) // ^ foramen magnum (skull) > L3 infants & l1 or 2 in children & adults v. Conus medullaris (inferior end of spinal cord) Filum terminale (long/central filament of ct from conus > coccyx; anchors spinal cord) Cadua equina (spinal nerve roots @end of vertebral canal / horse tail ) Cervical & lumbar enlargements: nerves for limbs arise here. Grooves divide into l/r: dorsal (posterior) median sulcus- gray wings touch edge ventral (anterior) median fissure - wider & deeper. White matter: outer region w/myelinated & unmyel. axons; allows communication between spinal cord & brain. Dorsal (posterior), ventral (anterior), & lateral funiculus. Ascending: carry sensory info from neurons > brain. Descending: carry motor info from brain > spinal cord.
