The Brain

An Introductory Guide

Extremely Under Construction!!!

Structure and LocationConnections... Function
Spinal Cord Fibers on the exterior, Cell bodies on interior Dorsal roots and ganglia: Sensory Ventral roots and ganglia: Motor Between Brain and Body Conveys Sensory information from body to brain; Conveys Motor impulses from brain to body
Cranial Nerves I to XII includes Optic (II), olfactory, auditory-vestibular, Vagus (heart and other parasympathetic functions) enter Medulla and Pons conveys impulses between brain and cranial areas
Brainstem
Medulla continuation of spinal cord into the brain; many cell nuclei autonomic nuclei for respiration, heart, digestion
Pons upward continuation; ascending and descending fiber tracts; many nuclei; feeding and facial expression
Midbrain (Mesencephalon) End of the basic tubular continuation bottom portion nuclei for cranial nerves; Red Nucleus and Substantia Nigra for motor control (Parkinson's) top portion (Tectum) nuclei for vision and audition; includes Inferior Colliculus Nucleus, an auditory nucleus
Cerebellum over the Pons; convoluted into lobules with a 2-3mm layer of cell bodies over underlying fiber and nuclei; very uniform in structure from vestibular system, spinal and cranial sensory nerves, auditory and visual systems, cerebral cortex and brainstem; to thalamus, brainstem, more regulates motor coordination & involved in learning
Thalamus group of nuclei anterior and dorsal to Midbrain; one ovoid in each cerebral hemisphere nuclei connected to and from many portions of brain final relay station for visual, auditory and somatic senses
Limbic System
Hypothalamus group of small nuclei in lower portion of Cerebrum at junction of Midbrain and Thalamus interconnects with many areas of brain directly controls pituitary gland; together with other portions of Limbic System, controls emotions: both pleasure and rage