PHSI 208 Lecture Notes - Lecture 10: Thalamus, Dorsal Root Ganglion, Grey Matter
Document Summary
Anatomy of the central nervous system: brain and spinal cord. Separated into gray matter and white matter: gray = consists of soma, dendrites and unmyelinated axons, white = mainly myelinated axons. Brain: gray matter outside, white matter inside. Spinal cord: white matter outside, gray matter inside. Major pathways for information flowing back and forth b/w the brain and the skin, joints and muscles of the body. Divided into four regions and each region is further divided into spinal segments: cervical (8, thoracic (12, lumbar (5, sacral (5, coccygeal (1) Each segments gives rise to a bilateral pair of spinal nerves, each nerve splits into roots: ventral root = motor (efferent, dorsal root = sensory (afferent) Gray matter = consists of sensory and motor nuclei. Separated into 3 regions: ventral horn = motor nuclei, lateral horn = autonomic nuclei, dorsal horn = sensory nuclei.
