Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Nervous system network models wikipedia , lookup
Synaptogenesis wikipedia , lookup
Axon guidance wikipedia , lookup
Limbic system wikipedia , lookup
Feature detection (nervous system) wikipedia , lookup
Stimulus (physiology) wikipedia , lookup
Development of the nervous system wikipedia , lookup
Neuropsychopharmacology wikipedia , lookup
Chapter 3 The Anatomy of the Nervous System The Systems, Structures, and Cells that Make Up Your Nervous System This multimedia product and its contents are protected under copyright law. The following are prohibited by law: • any public performance or display, including transmission of any image over a network; • preparation of any derivative work, including the extraction, in whole or in part, of any images; • any rental, lease, or lending of the program. Copyright © 2006 by Allyn and Bacon General Layout of the Nervous System Central Nervous System (CNS) • • Brain (in the skull) Spinal Cord (in the spine) Peripheral Nervous System (PNS) • • Located outside of the skull and spine Serves to bring information into the CNS and carry signals out of the CNS Copyright © 2006 by Allyn and Bacon General Layout of the Nervous System Peripheral Nervous System • Somatic Nervous System Afferent nerves (sensory) Efferent nerves (motor) • Autonomic Nervous System Sympathetic and parasympathetic nerves Both are efferent Copyright © 2006 by Allyn and Bacon Autonomic Nervous System All nerves are efferent Sympathetic and parasympathetic nerves generally have opposite effects Two-stage neural paths, neuron exiting the CNS synapses on a second-stage neuron before the target organ Copyright © 2006 by Allyn and Bacon Autonomic Nervous System Sympathetic Thoracolumbar “fight or flight” Second stage neurons are far from the target organ Parasympathetic Craniosacral “rest and restore” Second stage neurons are near the target organ Copyright © 2006 by Allyn and Bacon Copyright © 2006 by Allyn and Bacon Meninges, Ventricles, and CSF CNS - encased in bone and covered by three meninges • Dura mater - tough outer membrane • Pia mater - adheres to CNS surface • Arachnoid membrane - weblike Cerebrospinal fluid (CSF) • Fluid serves as cushion Copyright © 2006 by Allyn and Bacon Protecting the Brain Chemical protection • The blood-brain barrier – tightly-packed cells of blood vessel walls prevent entry of many molecules Physical protection • • • Skull Meninges Cerebrospinal fluid (CSF) Copyright © 2006 by Allyn and Bacon Cells of the Nervous System Neurons – structural classes Glial cells – various types, provide a wide variety of supportive functions • Multipolar • Unipolar • Bipolar • Interneurons Copyright © 2006 by Allyn and Bacon Copyright © 2006 by Allyn and Bacon Glial Cells Myelin producers Astrocytes – largest glia, many functions Microglia – involved in response to injury or disease • Oligodendrocytes (CNS) • Schwann cells (PNS) Copyright © 2006 by Allyn and Bacon Copyright © 2006 by Allyn and Bacon Terminology Note CNS Myelinproviding glia Oligodendrocytes PNS Schwann Cells Clusters of cell bodies Nuclei Ganglia (singular nucleus) (singular ganglion) Bundles of axons Tracts Nerves Copyright © 2006 by Allyn and Bacon Neuroanatomical Techniques Golgi stain – allows for visualization of individual neurons Nissl stain – selectively stains cell bodies Electron microscopy – provides information about the details of neuronal structure Copyright © 2006 by Allyn and Bacon Neuroanatomical Tracing Techniques Anterograde (forward) • tracing where axons project to Retrograde (backward) • tracing where axons are projecting from Copyright © 2006 by Allyn and Bacon Copyright © 2006 by Allyn and Bacon Copyright © 2006 by Allyn and Bacon Neuroanatomical Directions In humans, the spinal cord is bent. Top of the head = dorsal or superior Back = dorsal Medial – towards the middle Lateral – towards the side Proximal – close Distal - far Copyright © 2006 by Allyn and Bacon Sections of the Brain Horizontal – a slice parallel to the ground Frontal (coronal) – slicing bread or salami Sagittal – a midsagittal section separates the left and right halves Copyright © 2006 by Allyn and Bacon Copyright © 2006 by Allyn and Bacon The Spinal Cord Gray matter – inner component – primarily cell bodies White matter – outer – mainly myelinated axons Dorsal – afferent, sensory Ventral – efferent, motor Copyright © 2006 by Allyn and Bacon The Five Major Divisions of the Brain Copyright © 2006 by Allyn and Bacon The Five Major Divisions of the Brain Copyright © 2006 by Allyn and Bacon Major Structures of the Brain Myelencephalon = medulla • • Composed largely of tracts Origin of the reticular formation Metencephalon • • • Many tracts Pons – ventral surface Cerebellum - coordination Copyright © 2006 by Allyn and Bacon Major Structures of the Brain Mesencephalon • Tectum (dorsal surface) • Tegmentum (ventral) – 3 ‘colorful’ structures • Inferior colliculi – audition • Superior colliculi - vision • Periaqueductal gray – analgesia • Substantia nigra – sensorimotor • Red nucleus– sensorimotor Copyright © 2006 by Allyn and Bacon Major Structures of the Brain Diencephalon • • Thalamus – sensory relay nuclei Hypothalamus Regulation of motivated behaviors Controls hormone release by the pituitary Telencephalon • • • Cerebral cortex Limbic system Basal ganglia Copyright © 2006 by Allyn and Bacon Telencephalon – Cerebral Cortex Convolutions serve to increase surface area. Longitudinal fissure – a groove that separates right and left hemispheres Corpus callosum – largest hemisphereconnecting tract Copyright © 2006 by Allyn and Bacon Copyright © 2006 by Allyn and Bacon Telencephalon – Subcortical structures Limbic system – regulation of motivated behaviors • Mammillary bodies, hippocampus, amygdala, fornix, cingulate, septum Basal ganglia motor system • Amygdala, striatum (caudate nucleus + putamen), globus pallidus Copyright © 2006 by Allyn and Bacon Copyright © 2006 by Allyn and Bacon Copyright © 2006 by Allyn and Bacon