ACB 334 Lecture Notes - Lecture 4: Peripheral Nervous System, Parasympathetic Nervous System, Cranial Nerves
Document Summary
Pns components: subdivided into nerves entering or leaving the brain and sc that either: Voluntary system associated w/ afferent sensory and efferent motor fibres. Somatic sensory and motor nervous systems are present in all levels of the sc and some cranial nerves. Involuntary system associated w/ homeostasis of the body. Hard to inhibit; it keeps you safe; controlled by the hypothalamus. Autonomic sensory and motor are present in select regions of sc and some cranial nerves. *sympathetic and parasympathetic innervation is never at the same place. Includes sensory neurons of the dorsal root and cranial ganglia innervate muscles, skin and joints: provide sensory info about position of limbs, muscles, and the external environment. Somatic motor = ventral root: dermatome = sensory region innervated by a nerve root, myotome = the muscles innervated by a single nerve root. Both cranial and spinal nerves* can be subdivided into fibres innervating the soma and those innervating viscera.