Nervous System Health Science Technology I Dr. Wood.

Nervous SystemNervous System

Health Science Technology IHealth Science Technology I

Dr. WoodDr. Wood

ObjectivesObjectives

Identify the main parts of a neuron.Identify the main parts of a neuron.Describe the function of each of the main parts Describe the function of each of the main parts of the brain.of the brain.Understand the structure of and the messages Understand the structure of and the messages sent along the spinal cord.sent along the spinal cord.Name the three meninges and their function.Name the three meninges and their function.Contrast the actions of the sympathetic and Contrast the actions of the sympathetic and parasympathetic nervous system.parasympathetic nervous system.Understand the major diseases of the nervous Understand the major diseases of the nervous system.system.Define and understand the vocabulary words.Define and understand the vocabulary words.

Vocabulary WordsVocabulary Words

AfferentAfferentAutonomic nervous Autonomic nervous systemsystemBrainBrainCentral nervous systemCentral nervous systemCerebrospinal fluidCerebrospinal fluidCerebellumCerebellumCerebrumCerebrumDiencephalonDiencephalonEfferentEfferentHypothalamusHypothalamusMedulla oblongataMedulla oblongata

MeningesMeningesMidbrainMidbrainNervous systemNervous systemNeuronNeuronParasympatheticParasympatheticPeripheral nervous Peripheral nervous systemsystemPonsPonsSpinal cordSpinal cordSympatheticSympatheticThalamusThalamusVentriclesVentricles

Nervous systemNervous system

Complex, highly organized system that Complex, highly organized system that coordinates all the activities of the body coordinates all the activities of the body

Allows the body to respond and adapt to Allows the body to respond and adapt to changes that occurchanges that occur

NeuronNeuron

Nerve cellNerve cell

Basic structural unit of the nervous systemBasic structural unit of the nervous system

Parts of a neuronParts of a neuron

Cell body: contains the nucleusCell body: contains the nucleus

Dendrites: carry impulses to the cell bodyDendrites: carry impulses to the cell body

Axon: single nerve fiber that carries impulses Axon: single nerve fiber that carries impulses away from the cell bodyaway from the cell body

Myelin sheath: lipid covering around the axon Myelin sheath: lipid covering around the axon which increases the rate of impulse transmission which increases the rate of impulse transmission and insulates the axonand insulates the axon

Synapses: spaces between the axon of one Synapses: spaces between the axon of one neuron and the dendrites of other neuronsneuron and the dendrites of other neurons

Central nervous systemCentral nervous system

Consists of the brain and spinal cordConsists of the brain and spinal cord

BrainBrain

Mass of nerve tissue protected by the skullMass of nerve tissue protected by the skull

CerebrumCerebrum

Largest section of the brainLargest section of the brain

Divided in to lobes: frontal, parietal, Divided in to lobes: frontal, parietal, occipital and temporaloccipital and temporal

Responsible for reasoning, memory, Responsible for reasoning, memory, speech, sight, smell, hearing, voluntary speech, sight, smell, hearing, voluntary movementmovement

CerebellumCerebellum

Responsible for muscle coordination, Responsible for muscle coordination, balance and posturebalance and posture

DiencephalonDiencephalon

Contains the Contains the thalamusthalamus and and hypothalamushypothalamus

ThalamusThalamus: relay center and directs : relay center and directs sensory impulses to the cerebrumsensory impulses to the cerebrum

HypothalamusHypothalamus: regulates and controls the : regulates and controls the autonomic nervous system, temperature, autonomic nervous system, temperature, appetite, sleepappetite, sleep

MidbrainMidbrain

Conducts impulses between brain parts Conducts impulses between brain parts and for certain eye and auditory reflexesand for certain eye and auditory reflexes

PonsPons

Below the midbrainBelow the midbrain

Responsible for some reflex actions Responsible for some reflex actions including chewing, tasting, saliva including chewing, tasting, saliva productionproduction

Medulla oblongataMedulla oblongata

Lowest part of the brain stemLowest part of the brain stem

Connects with the spinal cord and is Connects with the spinal cord and is responsible for regulating heartbeat, responsible for regulating heartbeat, respiration, swallowing, coughing and respiration, swallowing, coughing and blood pressureblood pressure

Spinal CordSpinal Cord

Continues down from the medulla Continues down from the medulla oblongata and ends at L1 or L2oblongata and ends at L1 or L2

Protected and surrounded by the Protected and surrounded by the vertebraevertebrae

Carries Carries afferentafferent (sensory) messages up to (sensory) messages up to the brainthe brain

Carries Carries efferentefferent (motor) messages from (motor) messages from the brain to the nerves and then musclesthe brain to the nerves and then muscles

MeningesMeninges

Membranes that cover and protect the Membranes that cover and protect the brain and spinal cordbrain and spinal cord

Dura mater: thick outer layerDura mater: thick outer layer

Arachnoid membrane: web like middle Arachnoid membrane: web like middle layerlayer

Pia mater: inner layer attached to the brain Pia mater: inner layer attached to the brain and spinal cord and contains blood and spinal cord and contains blood vessels that nourish the brainvessels that nourish the brain

VentriclesVentricles

Hollow spaces in the brain that connect Hollow spaces in the brain that connect with each other and the subarachnoid with each other and the subarachnoid spacespace

Cerebrospinal fluidCerebrospinal fluid

Fluid in the ventricles, circulates Fluid in the ventricles, circulates continually, produced by choroid plexuscontinually, produced by choroid plexus

Shock absorber to protect the brain and Shock absorber to protect the brain and spinal cordspinal cord

Carries nutrients and helps remove some Carries nutrients and helps remove some metabolic wastemetabolic waste

Peripheral Nervous SystemPeripheral Nervous System

Consists of the cranial and spinal nervesConsists of the cranial and spinal nerves

Somatic nervous systemSomatic nervous system

12 pairs of cranial nerves12 pairs of cranial nerves

31 pair of spinal nerves: 8 cervical, 12 31 pair of spinal nerves: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral and 1 thoracic, 5 lumbar, 5 sacral and 1 coccygealcoccygeal

Carry messages to and from the spinal Carry messages to and from the spinal cord, both sensory and motorcord, both sensory and motor

Autonomic nervous systemAutonomic nervous system

Helps maintain a balance in the Helps maintain a balance in the involuntary functions of the body and involuntary functions of the body and allows the body to react in times of allows the body to react in times of emergencyemergency

2 divisions: sympathetic and 2 divisions: sympathetic and parasympatheticparasympathetic

Sympathetic nervous systemSympathetic nervous system

In times of emergency, fight or flight In times of emergency, fight or flight responseresponse

Increases heart rate, respiration & blood Increases heart rate, respiration & blood pressurepressure

Parasympathetic nervous systemParasympathetic nervous system

Works with the sympathetic nervous Works with the sympathetic nervous system to maintain balance or system to maintain balance or homeostasishomeostasis

After the emergency, slows heart rate and After the emergency, slows heart rate and respiration, lowers blood pressurerespiration, lowers blood pressure

Nervous system diseasesNervous system diseases

Cerebral palsyCerebral palsy

Caused by brain damageCaused by brain damage

Disturbance in voluntary muscle action Disturbance in voluntary muscle action

Cerebrovascular accidentCerebrovascular accident

Blood flow to the brain is impaired either Blood flow to the brain is impaired either by a hemorrhage or blockageby a hemorrhage or blockage

Common symptoms: weakness or Common symptoms: weakness or paralysis on one side, mental confusion, paralysis on one side, mental confusion, difficulty swallowing (dysphagia)difficulty swallowing (dysphagia)

EncephalitisEncephalitis

Inflammation of the brainInflammation of the brain

Caused by virus, bacteria, or chemical Caused by virus, bacteria, or chemical agentagent

Viral infection often carried by mosquitoViral infection often carried by mosquito

EpilepsyEpilepsy

Seizure disorderSeizure disorder

Abnormal electrical impulsesAbnormal electrical impulses

HydrocephalusHydrocephalus

Excessive accumulation of CSF in the Excessive accumulation of CSF in the ventriclesventricles

Abnormally large head, bulging eyes, Abnormally large head, bulging eyes, retardationretardation

MeningitisMeningitis

Inflammation of the meningesInflammation of the meninges

Caused by bacteria, virus, fungus or toxinsCaused by bacteria, virus, fungus or toxins

Multiple sclerosis (MS)Multiple sclerosis (MS)

Chronic, progressive disablingChronic, progressive disabling

Results from a degeneration of the myelin Results from a degeneration of the myelin sheathsheath

Parkinson’s diseaseParkinson’s disease

Chronic, progressive involving Chronic, progressive involving degeneration of brain cellsdegeneration of brain cells

Symptoms include tremors, stiffness, Symptoms include tremors, stiffness, shuffling gait, loss of facial expressionshuffling gait, loss of facial expression

ShinglesShingles

Inflammation of nerve cells cause by a Inflammation of nerve cells cause by a herpes virus, which also causes chicken herpes virus, which also causes chicken poxpox

Severe pain, vesicles along the nerve pathSevere pain, vesicles along the nerve path

ParalysisParalysis

Usually from injury, results in loss of Usually from injury, results in loss of function and sensation below the level of function and sensation below the level of injuryinjury

Hemiplegia: paralysis on one sideHemiplegia: paralysis on one side

Paraplegia: paralysis in legsParaplegia: paralysis in legs

Quadriplegia: paralysis of arms and legsQuadriplegia: paralysis of arms and legs

Image CitationsImage CitationsSlide 5, 7, 8, 10, 23, 26: Delmar Learning’s Medical Terminology Slide 5, 7, 8, 10, 23, 26: Delmar Learning’s Medical Terminology Image Library, Second Edition. Version 1.0, ISBN: 1-4018-1009-8.Image Library, Second Edition. Version 1.0, ISBN: 1-4018-1009-8.Slide 9: 1/13/06, The brain and spinal cord, Slide 9: 1/13/06, The brain and spinal cord, http://www.learnersonline.com/weekly/archive2001/week25/061801-http://www.learnersonline.com/weekly/archive2001/week25/061801-3.jpg3.jpgSlide 12: 1/13/06, Cerebellum,Slide 12: 1/13/06, Cerebellum,

http://www.morphonix.com/software/education/science/brain/game/shttp://www.morphonix.com/software/education/science/brain/game/specimens/cerebellum.gifpecimens/cerebellum.gifSlide 13: 1/13/06, Diencephalon, Slide 13: 1/13/06, Diencephalon, http://www.ims.uni-stuttgart.de/phonetik/joerg/sgtutorial/graphic/dienhttp://www.ims.uni-stuttgart.de/phonetik/joerg/sgtutorial/graphic/diencephalon.gifcephalon.gifSlide 14: 1/13/06, Midbrain and Cerebellum, Slide 14: 1/13/06, Midbrain and Cerebellum, http://www.stanford.edu/group/hopes/rltdsci/trinuc/f_f10midcereb.jpghttp://www.stanford.edu/group/hopes/rltdsci/trinuc/f_f10midcereb.jpgSlide 15: 1/13/06, Pons, Slide 15: 1/13/06, Pons, http://www.mult-sclerosis.org/pons.gifhttp://www.mult-sclerosis.org/pons.gifSlide 16: 1/13/06, Hindbrain, Slide 16: 1/13/06, Hindbrain, http://www.brainexplorer.org/brain-images/hindbrain.jpghttp://www.brainexplorer.org/brain-images/hindbrain.jpgSlide 20: 1/13/06, Slide 20: 1/13/06, http://www.merck.com/media/mmhe2/figures/fg076_1_2.gifhttp://www.merck.com/media/mmhe2/figures/fg076_1_2.gif

Image CitationsImage CitationsSlide 21: 1/13/06, Slide 21: 1/13/06, http://www.doereport.com/imagescooked/2475W.jpghttp://www.doereport.com/imagescooked/2475W.jpgSlide 24: 1/13/06, The Peripheral Nervous System, Slide 24: 1/13/06, The Peripheral Nervous System, http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/A/autonomic.http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/A/autonomic.gifgifSlide 30: 1/13/06, Sympathetic vs. Parasympathetic, Slide 30: 1/13/06, Sympathetic vs. Parasympathetic, http://homepage.psy.utexas.edu/homepage/class/Psy301/Salinas/shttp://homepage.psy.utexas.edu/homepage/class/Psy301/Salinas/sec2/Brain/03.GIFec2/Brain/03.GIFSlide 32: 1/13/06, Cerebral Palsy Images, Slide 32: 1/13/06, Cerebral Palsy Images, http://www.qub.ac.uk/cm/os/ortho/C/cerebral/c14_7.gifhttp://www.qub.ac.uk/cm/os/ortho/C/cerebral/c14_7.gifSlide 36: 1/13/06, Hydrocephalus, Slide 36: 1/13/06, Hydrocephalus, http://www.trejos.com/Trejos/HydrocephalusIII.JPGhttp://www.trejos.com/Trejos/HydrocephalusIII.JPGSlide 36: 1/13/06, Slide 36: 1/13/06, http://www.pediatriconcall.com/cgi_bin/congenitalhttp://www.pediatriconcall.com/cgi_bin/congenital%20hydrocephalus.JPG%20hydrocephalus.JPGSlide 37: 1/13/06, Meningitis strikes campus, Slide 37: 1/13/06, Meningitis strikes campus, http://www.statenews.com/editions/020700/meningitis.JPGhttp://www.statenews.com/editions/020700/meningitis.JPG

Image CitationsImage CitationsSlide 38: 1/13/06, www.ms150.orgSlide 38: 1/13/06, www.ms150.orgSlide 39: 1/13/06, Slide 39: 1/13/06, http://www.cnn.com/SHOWBIZ/Movies/9909/28/fox.parkinsons/fox.jhttp://www.cnn.com/SHOWBIZ/Movies/9909/28/fox.parkinsons/fox.jpgpgSlide 40: 1/13/06, http://www.drpodell.org/images/shingles-Slide 40: 1/13/06, http://www.drpodell.org/images/shingles-treaments.jpgtreaments.jpgSlide 41: 1/13/06, Slide 41: 1/13/06, http://www.andylee.freeuk.com/Images/christopher_reeves.jpghttp://www.andylee.freeuk.com/Images/christopher_reeves.jpg