The Nervous SystemThe Nervous System

Unit 6Unit 6

ObjectivesObjectives

• 1.1.  Describe the 3 parts to the neuronDescribe the 3 parts to the neuron• 2.2.  List the main divisions of the List the main divisions of the

nervous systemnervous system• 3.3. List the functions of the nervous List the functions of the nervous

systemsystem• 4.Identify and label parts of the brain 4.Identify and label parts of the brain

and major nerve and major nerve • 5. List some common brain disorders5. List some common brain disorders

General Divisions of LaborGeneral Divisions of Labor

• Central Nervous SystemCentral Nervous System• Peripheral Nervous SystemPeripheral Nervous System• Autonomic Nervous SystemAutonomic Nervous System

Central Nervous SystemCentral Nervous System

• Named for: Named for: LocationLocation• Consists of: Consists of: Brain and Spinal CordBrain and Spinal Cord• Function: Function: Control CenterControl Center

Peripheral Nervous Peripheral Nervous SystemSystem

• Named for: Named for: LocationLocation • Consists of: Consists of: Spinal, Somatic, and Spinal, Somatic, and

Cranial Nerves (Receptors)Cranial Nerves (Receptors)• Function: Function: Relay CenterRelay Center

Autonomic Nervous Autonomic Nervous SystemSystem

• Named for: Named for: FunctionFunction• Consists of: Consists of: Midbrain, Pons, Midbrain, Pons,

Medulla Oblongata, Spinal Cord, Medulla Oblongata, Spinal Cord, and Peripheral Branchesand Peripheral Branches

• Functions: Functions: Independent Life Independent Life FunctionsFunctions

ANSANS• Broken down into Broken down into

– SympatheticSympathetic NS- activates for F/F NS- activates for F/F– ParasympatheticParasympathetic NS- calms body NS- calms body

downdownOrgan Sympathetic Parasympathetic

Pupil Dilate Constrict

Glands Sweat Salivary, Tears

Heart Rate Accelerates Slows

Bronchial Tubes Dilate Constrict

Digestion Inhibited Stimulated

Urine Volumes drops Volume Increases

Liver Glucose Stims. Release Inhibits Release

Main FunctionsMain Functions

• CommunicationCommunication• CoordinationCoordination• OrientationOrientation• AssimilationAssimilation

What’s It Made of?What’s It Made of?

• NeuronNeuron: Functional unit that makes : Functional unit that makes up the nervous system, triggers to up the nervous system, triggers to transmit informationtransmit information

Neuron StructureNeuron Structure

NeurogliaNeuroglia: Supporting cells that aid the : Supporting cells that aid the neuron by feeding, protecting, and neuron by feeding, protecting, and speeding up transmissionsspeeding up transmissions

• 65% of 65% of

brain tissuebrain tissue• To surround neurons and To surround neurons and

holdhold them in place them in place• To supply nutrients and To supply nutrients and

oxygenoxygen to neurons to neurons• To To insulateinsulate one neuron one neuron

from anotherfrom another• To destroy To destroy pathogenspathogens

and remove dead and remove dead neurons.neurons.

How do neurons communicate?• Neurons “connect” at a space Neurons “connect” at a space

called a called a SYNAPSESYNAPSE• They create They create action potentials action potentials that that

send a signal (from ions) that send a signal (from ions) that causes a release of causes a release of neurotransmittersneurotransmitters (chemical (chemical signals) that either excite or inhibit signals) that either excite or inhibit the next neuronthe next neuron

All or Nothing ResponseAll or Nothing Response

• Neurons “rest” at -70mVNeurons “rest” at -70mV• When voltage changes to +40 mV, When voltage changes to +40 mV,

the “threshold” has been reachedthe “threshold” has been reached• The neuron The neuron fires!!• NeurotransmittersNeurotransmitters

Are released!Are released!

NeurotransmittersNeurotransmitters

• Acetylcholine-Acetylcholine- excitatory (arousal, excitatory (arousal, attention, memory)attention, memory)

• Dopamine-Dopamine- inhibitory (attention, inhibitory (attention, learning, movement, pleasure)learning, movement, pleasure)

• SerotoninSerotonin –inhibitory (anxiety, –inhibitory (anxiety, dreaming, eating, sleep, mood, pain)dreaming, eating, sleep, mood, pain)

• Noradrenalin/Norepinephrine- Noradrenalin/Norepinephrine- excitatory (activity, alert, heart)excitatory (activity, alert, heart)

More Vocab…More Vocab…

• BrainBrain: Control center of nervous : Control center of nervous system, also called cerebrumsystem, also called cerebrum

• LobesLobes: Division of the brain with : Division of the brain with specific functionsspecific functions

• Cranial NervesCranial Nerves: 12 pairs abbrev. By : 12 pairs abbrev. By roman numerals that control head roman numerals that control head and neckand neck

Brain TermsBrain Terms

Lobes of the BrainLobes of the Brain

• FrontalFrontal Lobe Lobe– Location: Front 50% of brainLocation: Front 50% of brain– Function: Intellect, Reasoning, Function: Intellect, Reasoning,

Creativity, Social Awareness, Creativity, Social Awareness, Language andLanguage and

PersonalityPersonality

(movement as well)(movement as well)

Lobes of the BrainLobes of the Brain

• Parietal LobeParietal Lobe– Location: Top, Posterior portion Location: Top, Posterior portion – Function: Sensory Information (pain Function: Sensory Information (pain

and touch), spatial relationshipsand touch), spatial relationships

Sensory MapsSensory Maps

• All sensory information is received All sensory information is received in the parietal in the parietal cortexcortex

• Is there an Is there an eveneven amount of neurons amount of neurons dedicated to every sense and body dedicated to every sense and body part?part?

• NO!NO!• HomonculusHomonculus: diagram that : diagram that

represents the amount of space represents the amount of space dedicated to each body partdedicated to each body part

Sensory HomunculusSensory Homunculus

Lobes of the BrainLobes of the Brain

• Occipital LobeOccipital Lobe::– Location: Posterior Back, bottomLocation: Posterior Back, bottom– Function: Visual area that interprets Function: Visual area that interprets

shape, color, distance, etc. and sends shape, color, distance, etc. and sends info. to be recognizedinfo. to be recognized

Lobes of the BrainLobes of the Brain

• Temporal LobeTemporal Lobe::– Location: Posterior lateral portionsLocation: Posterior lateral portions– Function: Smell, taste, hearing (music, Function: Smell, taste, hearing (music,

noise, speech noise, speech word to thought, word to thought, memory)memory)

Overall View of FunctionOverall View of Function

Cerebral HemispheresCerebral Hemispheres

• Location: Rt. vs. Lt., separated by Location: Rt. vs. Lt., separated by longitudinal fissurelongitudinal fissure

• Function: Function: LeftLeft= language and = language and reasoningreasoning

RightRight=Space=Space, pattern, , pattern, artistic, music, artistic, music,

imagination imagination

Corpus CallosumCorpus Callosum: nerve : nerve fibers that connect the 2 hemispheresfibers that connect the 2 hemispheres

HypothalamusHypothalamus“Master Gland”“Master Gland”

• Location: Deep, inner portion of Location: Deep, inner portion of brainbrain

• Function: Regulates metabolism Function: Regulates metabolism and glandsand glands

Pituitary GlandPituitary Gland

• Location: Deep in the sella tursicaLocation: Deep in the sella tursica• Function: Secretes hormones Function: Secretes hormones

including ADH, oxytocin, TSH, LH, including ADH, oxytocin, TSH, LH, ACTHACTH

• Extremely important gland for both nervous and endocrine system

Brain Anatomy and PhysBrain Anatomy and Phys

• Pineal Gland:Pineal Gland:– Location: Superior to brainstemLocation: Superior to brainstem– Function: Circadian RhythmsFunction: Circadian Rhythms

•Pons:Pons:

–Location: Brain StemLocation: Brain Stem

–Function: Relays sensory information Function: Relays sensory information b/t cerebrum and cerebellum (possibly b/t cerebrum and cerebellum (possibly involved in dreaming)involved in dreaming)

Brain Anatomy and PhysBrain Anatomy and Phys

• Medulla OblongataMedulla Oblongata::– Location: on the brain stemLocation: on the brain stem– Function: Autonomic Fxn’s (heart and Function: Autonomic Fxn’s (heart and

lungs)lungs)• CerebellumCerebellum::

– Location: Base of brainLocation: Base of brain– Function: Sensory Input vs. Motor, Function: Sensory Input vs. Motor,

coordinate movement, posture, coordinate movement, posture, balance, and equilibriumbalance, and equilibrium

Cranial NervesCranial Nerves

• II-Smell-Smell• IIII-Vision-Vision• IIIIII-Eye Movement-Eye Movement• IVIV-Eye Rotation-Eye Rotation• VV-Face Sensations-Face Sensations• VIVI-Eye Move Away-Eye Move Away• VIIVII-Face Expressions -Face Expressions

and 2/3 tongueand 2/3 tongue

Cranial NervesCranial Nerves

• VIIIVIII- Sound, rotation, - Sound, rotation, gravity, balancegravity, balance

• IXIX-taste, salivary -taste, salivary glandgland

• XX-heart and other -heart and other ANS organsANS organs

• XIXI-Neck Muscles-Neck Muscles• XIIXII-Tongue Muscles-Tongue Muscles

Ear Drum Hairs-ReceptorsEar Drum Hairs-Receptors

Retina of EyeRetina of Eye

Nervous System DisordersNervous System Disorders

• Can be environmental, genetic, or Can be environmental, genetic, or bothboth

• Common disorders include:Common disorders include:– Parkinson’s DiseaseParkinson’s Disease– StrokeStroke– Alzheimer’s DiseaseAlzheimer’s Disease– MeningitisMeningitis

What does the line show us?What does the line show us?

Brain “terms”Brain “terms”

• GyrusGyrus: bump/bulge on cortex: bump/bulge on cortex• SulcusSulcus: Groove in the cortex: Groove in the cortex• CortexCortex: Outer most layer of brain: Outer most layer of brain• Afferent NervesAfferent Nerves: bring in somatic : bring in somatic

infoinfo• Efferent NervesEfferent Nerves: Take out info : Take out info

(motor, gland, etc.)(motor, gland, etc.)

Terms RevisitedTerms Revisited

Cerebral CortexCerebral Cortex

• Dark PurpleDark Purple

Off Topics…Off Topics…

• The Science Of HeartacheThe Science Of Heartache• Brain TricksBrain Tricks• Can you live with half a brain?Can you live with half a brain?

Make the connection…Make the connection…

• Lower mammals tend to have a Lower mammals tend to have a thinner cortex with fewer gyri and thinner cortex with fewer gyri and sulcisulci