The Brain Named Brian

Intro to the Nervous SystemNervous System has 2 types of cells: 1. Neuron 2. Glial cells – support cells

NeuronBasic structural unit of the nervous system Maintains function of the nervous tissueIt is the nerve cell. myelin is ‘whiteish’ color

Glial CellsGlial (glue) or neuroglial cells are the helper

cellsThey support the Neuron, more glials than

neuronsInvolved in the nutrition and maintenance of

the nerve cells

Parts of a NeuronThe soma (cell body) - contains the nucleus of

the cell which is the control centerDendrite - receives the message and sends it

to the somaAxon - sends the message to the muscle, next

neuron etc.Axon terminal- end of the axon

Neurons (con’t)The axon is covered by myelin sheath – this is a

lipid covering to protect the axon- like a jelly rollSynapse- is the space between neurons- impulses

coming from one axon to the next “jump” to get to the dendrite

Neuronsdraw a picture of a neuron:

Synapse DiscussionBriefly Study this Picture:

Turn to your neighbor and discuss what you see.

dopamine is ‘feel good’ neurotransmitter

Functions of the nervous system1. constantly monitors info from outside and

inside the body via receptors2. perceives info in the brain; based on

memory3. evaluates info - detects heat4. sends out motor direction- either a reflex

or you consciously jerk your hand away from heat, or both

5. memory- to remember a learned behaviorInformation is monitored, received,

perceived, evaluated, a response is sent, and the event is stored in memory.

Nervous systemCNS - central nervous system=brain/spinal cord

PNS - peripheral nervous system=cranial nerves, spinal nerves. PNS has afferent(sensory)and efferent(motor) nerves.

PNS has somatic nerv syst and visceral nerv syst.

Somatic NS has afferent and efferent nerves.

visceral nerv syst has afferent and motor(autonomic NS)

ANS has sympathetic and parasympathetic, motor only

CNSCentral Nervous System controls the

brain, spinal cord• Brain controls many functions like:

sleep, sexual activity, memory, emotion, movement, hunger thirst and thought processes.• Spinal Cord extends nerve fibers from the

brain and acts as a switching or relay terminal for the peripheral nervous

system.

PNSPeripheral Nervous System

- controls cranial, spinal and autonomic nerve

- 31 pairs exit from the spinal cord. - each has a posterior and anterior

brancha. posterior carries info to the

spinal cord (afferent)b. anterior carries impulses to

the muscles (efferent)

ANS(aka visceral motor division

Contains Sympathetic and Parasympathetic systemsSympathetic= fight or flight- you may feel fear

or anger-you are reacting to an emergency Increased heart rate Liver releases & increases glucose Thyroid is stimulated-sweating Kidney vessels constrict

ANS (con’t)Jane was walking and a dog started running

at her and barking. Discuss with your partner:

Which part of the ANS would you say was activated?

What would some signs be?

ANSParasympathetic system- rest and reposeYou sleep and slobber on your pillowHeart rate is decreasedAppetite is increased

ANS (con’t)Albert was sitting in class and he heard his

stomach growl. Discussion:

Which ANS system was activated?

What signs did he present?

Anatomy of the Brain(100billion neurons)Cerebrum----who is Abby norm Al?

largest highest section of the brain the outer part is arranged in folds called convolutions.dips are sulci, raises are gyriresponsible for reasoning, thought, memory, speech, sensation,

sight, smell, hearing and voluntary body movementhttps://www.youtube.com/watch?v=nY1aB9w1zMc

Anatomy of the BrainCerebellum

section just below the cerebrumresponsible for muscle coordination, balance

and posture, and muscle tone

Anatomy of the BrainDiencephalon

the section located between the cerebrum and midbrain divided into 2 sections: 1.Thalamus-acts as a relay center and directs

sensory impulses to the cerebrum2.Hypothalamus- controls the ANS,

temperature, appetite, water balance, sleep, blood vessel constriction and dilation

Anatomy of the BrainMidbrain

located below the cerebrum at the top of the brain stem.

responsible for conducting impulses certain eye and auditory reflexes

Anatomy of the BrainPons

located below the midbrain in the brain stem.conducts messages to other parts of the brain -

reflex actions like chewing, tasting, saliva production, and assisting with respirations

Anatomy of the BrainMedulla oblongata

lowest part of the brain stem connects brain with the spinal cordresponsible for regulating heartbeat,

respirations, swallowing, coughing, and blood pressure

Anatomy of the BrainSpinal Cord

continues down from the medulla oblongata to the 1st or 2nd lumbar vertebrae

surrounded by vertebrae responsible for many reflex actions carries sensory or afferent messages up to the braintakes efferent messages from the brain through nerves to tissues

Anatomy of the BrainMeninges

three membranes cover the brain and protect the spinal cord (PAD---pia,arachnoid,dura)1. dura mater - thick tough outer layer2. arachnoid membrane - middle layer that is delicate

like a web3. pia mater - attaches to the brain and spinal cord-

contains vessels that nourish the nerve tissue

Anatomy of the BrainVentricles

4 hollow spaces in the brainconnect with each other and with the

space under the arachnoid membrane (subarachnoid space)

filled with cerebrospinal fluid(CSF)that circulates between the ventricles and through the subarachnoid space

fluid acts as a shock absorber to protect the brain and spinal cord.

Anatomy of the BrainChoroid Plexus

structures that produce the cerebrospinal fluidArachnoid villi- absorb the cerebrospinal fluid

and return to the blood stream.

The Brain Named Brian

Part 2 - Pathologies

Pathology of the brainHemorrhage-an artery bursts and bleeds into

surrounding tissues. Blood pools and begins to clot, and forms a hematoma.

This is considered a stroke or cerebrovascular accident or CVA

This puts pressure on other parts of the brainThis reduces circulation to the other portions

of the brain and brain tissue dies

pathologiesCauses of hemorrhage-Trauma- mostly for under 50High blood pressure- over prolonged time

weakens vessel wallsAneurysm- weakening of a blood vessel wall

that swells- it can burst

pathologiesSigns and symptoms of hemorrhage-Sudden severe headacheSeizure with no history of seizuresWeakness in arm or legNausea and vomitingDifficulty speakingLoss of coordination

pathologyTreatment- must reduce the swelling in the

brainMedications to stop vomitingSteroids to reduce swellingSurgery to remove the clotDiuretic to reduce swelling

Pathologies of neurologyCerebral palsy- lack of O2 to the brain, birth

injuries, German Measles, and infections can cause CP

It is a disturbance in voluntary muscle actionThere may also be problems with sensation, depth

perception, and communication ability. Difficulty with cognition and epilepsy is found in about one-third of cases.

Pathology-cerebral palsy

Signs and symptoms:stiff or tight muscles and exaggerated

reflexes (spasticity); walking with one foot or leg dragging; walking on the toes, a crouched gait, or a “scissored” gait; and muscle tone that is either too stiff or too floppy

pathologyThere is no cure for CPPhysical therapy and occupational therapyBotox shots in spastic musclesMuscle relaxants

pathologyGuillain-Barre syndrome is a disorder in which

the body's immune system attacks part of the peripheral nervous system.

>the immune system starts to destroy the myelin sheath that surrounds the axons of many peripheral nerves, or even the axons themselves

paralyis starts at hands and legs, works toward the trunk.

pathologies treatment of GB- immunoglobulin- a donor

protein that helps decrease allergic reaction of the body.

Steroids to decrease inflammationWatch for respiratory distress, patients can

become passive in about 3 weeks after onsetGB is not contagiousDiagnose with NCV test or CSF test

pathologiesEpilepsy-seizure syndrome associated with

abnormal electrical impulses in the neurons in the brain.

Causes are brain injury, trauma, tumors, toxins, and idiopathic- no one knows why

pathologyAbsence seizures- petite mal- loss of

consciousness for a few secondsTonic clonic- grand mal- very severe with loss

of consciousness lasting seconds to minutes.

pathologySigns and symptoms of grand mal seizuresThrashing movementsHypersalivationViolent shakingFoaming at the mouthLoss of body functions

pathologyTreatment- during seizure put the patient on

their side to avoid aspirationPatient will look ashen-this is normalStart CPR if the patient stops breathingGive anticonvulsant therapy to help control

pathologyMeningitis- inflammation of the meninges of

the brain and or spinal cordCaused by an infection ( fungus, bacteria,

virus)

pathologySigns and symptoms of meningitisHigh feverStiff neckHeadacheNausea and vomitingDeliriumconvulsions

pathologyTreatment for meningitisAntibioticsAnticonvulsantPain meds

pathologyMultiple sclerosis- a progressive disabling

condition resulting from degenerating myelin sheath

Usually see this in people of their 20-40’sCause is unknown

pathologySigns and symptoms of MSVisual disturbanceWeaknessFatiguePoor coordinationTingling and numbnessCan lead to tremors spasticity and

incontinence

pathologyThere is no cure for MSCan do physical therapyMuscle relaxantsSteroids

pathologyParkinson’s- paralysis agitans- degeneration

of the brain cells. Usually in people over 50

pathologySigns and symptoms of Parkinson's:TremorsStiffnessMuscular rigidityShuffling gaitLoss of facial expressionBehavioral changes

pathologiesTreatment for ParkinsonsThere is no cureLevodopa- carbidopaBrain surgery to remove the part of the brain

that controls involuntary movement

brainthe cranial nerves………