Overview Discussion of Library Assignment Brief Anatomy and Physiology of Nervous System Tissues of the Nervous System Transmission of Nerve Impulses Central Nervous System Brain Area Peripheral Nervous System Cranial Nerves Spinal Nerves Autonomic Nervous System Diseases Procedures

Chapter Fourteen Nervous System

Functions of the Nervous System Control center for all body activities Responds and adapts to changes that occur both inside and outside the body (Ex: pain, temperature, pregnancy)

Tissues of the Nervous System Two principal tissue types of the nervous system: neurons (nerve cells) the structural and functional units of the nervous system specialized conductors of impulses neuroglia (supporting tissues)

Figure 14.2 Two main types of nerve cells.

Central Nervous System Neurons : microscopic nerve cells that make up the brain, spinal cord, and nerves - 30,000 neurons can fit on a pinhead

Anatomy of a Neuron Each neuron contains: - Cell body with nucleus - Dendrites : fibers that receive messages from other neurons - Axons : fibers that send messages to other neurons

Neurons do NOT touch; there is a gap between them called a synapse Messages are sent across the synapses by special chemicals called neurotransmitters

Neuron Video Synapse Synaptic cleft Neurotransmitters https://youtu.be/o9p2ou1IyC0 https://faculty.washington.edu/chudler/synapse.html Listen for these words Synapse Synaptic cleft Neurotransmitters

Cells of the Nervous System Neurons (neur/o) Dendrites (dendr/o) Cell body ganglion (gangli/o) Axon Myelin sheath Synapse Neurotransmitters - A chemical that is released from a nerve cell which thereby transmits an impulse from a nerve cell to another.

Tissues of the Nervous System There are several types of neurons, three of which are: Sensory neurons – afferent nerves convey towards the center, inflowing, conducting Afferent - ad + ferre, to carry Motor neurons – most are efferent carries away from synaptic ending to the muscle or organ to be innervated Efferent - [L. efferens, fr. effero, to bring out]- to conduct out

Differences

Organization of the Nervous System Central Nervous System (CNS) Brain (encephal/o) and spinal cord (myel/o) Peripheral nervous system (PNS) 12 pairs Cranial nerves 31 pairs spinal nerves Somatic Nervous System Autonomic Nervous System Sympathetic – fight or flight Parasympathetic – rest and digest

Central Nervous System: Brain Cerebellum- maintenance of balance, posture, coordination of voluntary movement and motor learning and language Diencephalon “Between Brain” Thalamus – relay center for sensory impulses Hypothalamus –regulator of ANS, controls some metabolic activities Brainstem Midbrain Pons Medulla oblongata

Central Nervous System: Brain Cerebrum

Mind Mapping https://youtu.be/DfgkAJmp9-A

Peripheral Nervous System Nerves : visible bundles of axons and dendrites that extend from the brain and spinal cord to all other parts of the body

On old Olympus' towering top a Fin and German viewed some hops see page 483 for list O: olfactory nerve (CN I) O: optic nerve (CN II) O: oculomotor nerve (CN III) T: trochlear nerve (CN IV) T: trigeminal nerve(CN V) A: abducens nerve (CN VI) F: facial nerve (CN VII) A: auditory (or vestibulocochlear) nerve (CN VIII) G: glossopharyngeal nerve (CN IX) V: vagus nerve (CN X) S: spinal accessory nerve (CN XI) H: hypoglossal (CN XII)

Vasovagal Syncope Vasovagal attack The vasovagal response is a complex signaling of the brain that dilates the blood vessels in the legs, slows the heart rate, and very often causes fainting, which is also called vasovagal syncope.

The Spinal Cord Spinal cord 31 Pairs of spinal nerves 8 pairs of cervical spinal nerves 12 Thoracic spinal nerves 5 pairs of lumbar spinal nerves 5 pairs of sacral spinal nerves 1 pair of coccygeal spinal nerves Two roots Dorsal/Sensory Root (afferent) Ventral root (efferent) Spinal cord

Prefixes and Suffixes an- hemi- mono- para- poly- quadri- -cele -esthesia -graphy -gram -ia -lepsy -lysis -paresis -plegia

Combining Forms cerebell/o mening/o cerebr/o myel/o crani/o narc/o electr/o encephal/o esthesi/o hemat/o mening/o myel/o narc/o neur/o somn/o

Signs and Symptoms Amnesia Aphasia Ataxia Bradykinesia Cephalalgia Dysphasia Gait, abnormal Neuralgia Paresthesia Seizure Syncope Tremors Vertigo

Congenital Disorders Cerebral palsy (CP) Hydrocephalus

Traumatic Conditions Coma Concussion Hematoma Epidural Subdural

Degenerative Disorders Alzheimer disease (AD) Amyotrophic lateral sclerosis (ALS) Lou Gehrig disease Multiple sclerosis Parkinson disease Demyelination

Nondegenerative Disorders Epilepsy Narcolepsy Bell palsy Bell palsy

Infectious Diseases Encephalitis Meningitis

Vascular Disorders Cerebrovascular accident (CVA) Transient ischemic attack (TIA) CVA

Paralytic Conditions Paralysis Hemiparesis Hemiplegia Paraparesis -plegia (stroke related) vs. –paresis (weakness to no movement) Hemiparesis Hemiplegia Paraparesis Paraplegia Quadriparesis Quadriplegia Paralysis

Pharmacology Analgesics Anesthetics Anticonvulsants Hypnotics

Imaging Cerebral angiography Myelography Angiography

Diagnostic Tests Lumbar puncture (LP)