CENTRAL NERVOUS SYSTEM Chapter 8 CENTRAL NERVOUS SYSTEM

INTRODUCTION TO THE CENTRAL NERVOUS SYSTEM Functions of the central nervous system: Communication and coordination system in the body Receives messages from stimuli Brain interprets message Brain responds and carries out activity Reasoning and intelligence ©2004 Delmar Learning, a division of Thomson Learning, Inc.

INTRODUCTION TO THE CENTRAL NERVOUS SYSTEM Nervous tissue consists of two types of nerve cells: Neuroglia - cells that insulate, support and protect neurons Neurons - pass nerve impulses Sensory neurons (afferent) Motor neurons (efferent) Associative neurons (interneurons) ©2004 Delmar Learning, a division of Thomson Learning, Inc.

INTRODUCTION TO THE CENTRAL NERVOUS SYSTEM ©2004 Delmar Learning, a division of Thomson Learning, Inc.

INTRODUCTION TO THE CENTRAL NERVOUS SYSTEM Membrane excitability is the electric charge created by impulses in the nerve Synapse - messages go from one cell to the next Synaptic cleft - space between axon or one cell and dendrite of another ©2004 Delmar Learning, a division of Thomson Learning, Inc.

DIVISIONS OF THE NERVOUS SYSTEM There are 3 divisions of the nervous system: Central nervous system - brain and spinal cord Peripheral nervous system - nerves of the body Autonomic nervous system - peripheral nerves and ganglia ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. THE BRAIN Memory Short term Long term Coverings of the brain Dura mater Arachnoid mater Pia mater ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. THE BRAIN The brain contains four lined cavities called cerebral ventricles Right lateral ventricle Left lateral ventricle Third ventricle Fourth ventricle Cerebral fluid serves as liquid shock absorber ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. THE BRAIN ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. CEREBRUM The cerebrum is divided into 2 hemispheres; each hemisphere is divided into: frontal lobe parietal lobe occipital lobe temporal lobe ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. CEREBRUM The cerebral surface is covered with furrows and ridges Sulci - Shallow grooves Fissures - deeper grooves Longitudinal fissure Transverse fissure Central fissure Lateral fissure Parieto-occipital fissure ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. CEREBRUM Each lobe of the cerebral hemispheres control different functions Frontal lobe - motor functions Parietal lobe - sensory Occipital lobe - eyesight Temporal lobe - auditory and olfactory senses ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. CEREBRUM ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. DIENCEPHALON Thalamus Located between the cerebrum and midbrain Acts as a relay station for incoming and outgoing nerve impulses ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. DIENCEPHALON Hypothalamus Autonomic nervous control Cardiovascular control Temperature control Appetite control Water balance Manufacture of oxytocin Gastrointestinal control Emotional state Sleep control ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. CEREBELLUM Consists of two hemispheres Right cerebellar hemisphere Left cerebellar hemisphere Controls all skeletal muscle body functions: Maintenance of balance Maintenance of muscle tone Coordination of muscle movement ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. BRAIN STEM Brain stem is made of 3 parts: Midbrain Pons Medulla ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. SPINAL CORD The spinal cord functions as both a reflex center and a conduction pathway to and from the brain ©2004 Delmar Learning, a division of Thomson Learning, Inc.

DISORDERS OF THE CENTRAL NERVOUS SYSTEM Meningitis Encephalitis Epilepsy Cerebral palsy Poliomyelitis Parkinson’s disease Hydrocephalus Multiple sclerosis Dementia Alzheimer’s disease Brain tumors Hematoma ©2004 Delmar Learning, a division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. Activity With a partner look up each of the listed Central Nervous system disorders and write symptoms of them. Add this to your notes Individually Draw and label a brain (draw to scale) (color the different lobes and parts) turn this in ©2004 Delmar Learning, a division of Thomson Learning, Inc.

THE PERIPHERAL AND AUTONOMIC NERVOUS SYSTEM Chapter 9 THE PERIPHERAL AND AUTONOMIC NERVOUS SYSTEM

PERIPHERAL NERVOUS SYSTEM Includes all of the nerves of the body and ganglia Connects the central nervous system to various body structures Controls the involuntary (automatic) activities of vital internal organs Acts as a reflex center of body © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. NERVES Sensory (afferent) nerve - fibers carry impulses from sense organs to the brain or spinal cord Motor (efferent) nerve - fibers carry impulses from brain or spinal cord to muscles or glands Mixed nerve - contains both sensory and motor fibers © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

CRANIAL AND SPINAL NERVES The cranial nerves are 12 pairs of nerves that begin in various areas of the brain The spinal nerves originate at the spinal cord and go through openings in the vertebrae All 31 pairs of spinal nerves are mixed nerves © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

AUTONOMIC NERVOUS SYSTEM Includes nerves, ganglia, and plexuses that carry impulses to all smooth muscle, secretory glands, and heart muscle Regulates the activities of the visceral organs © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

AUTONOMIC NERVOUS SYSTEM There are two divisions: Sympathetic system - consists of two cords of nerve fibers and ganglia extending from base of brain down through spinal column Parasympathetic system Vagus nerve - chest and neck Pelvic nerve - hip region © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

DISORDERS OF THE PERIPHERAL NERVOUS SYSTEM Neuritis Sciatica Neuralgia Trigeminal neuralgia Bell’s palsy Shingles (herpes zoster) Carpal tunnel syndrome © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

©2004 Delmar Learning, a division of Thomson Learning, Inc. Activity With a partner look up the listed disorders of the peripheral nervous system write the symptoms of each add this to your notes. Individually draw a nerve bundle fiber and label it add this to your notes ©2004 Delmar Learning, a division of Thomson Learning, Inc.