Chapter 2 biological perspective notes

Chapter 2 BiologicalChapter 2 Biological
PerspectivePerspective
 Overview of the Nervous SystemOverview of the Nervous System
 Nervous System: A network of cells thatNervous System: A network of cells that
carries information to and from all parts of thecarries information to and from all parts of the
body.body.
 Neurons and NervesNeurons and Nerves
 Neuroscience: Deals with the structure andNeuroscience: Deals with the structure and
function of neurons, nerves, and nervous tissue,function of neurons, nerves, and nervous tissue,
especially focusing on their relationship to behaviorespecially focusing on their relationship to behavior
and learningand learning

Structure of the NeuronStructure of the Neuron
 Each cell in the body has a specialEach cell in the body has a special
functionfunction
 Most cells have three things in commonMost cells have three things in common
 A nucleus, a cell body, and a cell membraneA nucleus, a cell body, and a cell membrane
 Neuron: The basic cell that makes up theNeuron: The basic cell that makes up the
nervous system and that receives and sendsnervous system and that receives and sends
messages within that systemmessages within that system
 Dendrites: Branchlike structures that receiveDendrites: Branchlike structures that receive
messages from other neuronsmessages from other neurons

Neurons and NervesNeurons and Nerves
 Dendrites are attached to the cell bodyDendrites are attached to the cell body
(Soma): Maintains the life of the cell(Soma): Maintains the life of the cell
 Axon: Tubelike structure that carries theAxon: Tubelike structure that carries the
neural message to other cellsneural message to other cells
 People use every cell in the brain forPeople use every cell in the brain for
somethingsomething
 Neurons make up 10% of the brainNeurons make up 10% of the brain
 The rest are glial cells that provide support forThe rest are glial cells that provide support for
the neurons and allow them to grow and thrivethe neurons and allow them to grow and thrive

Nerves and NeuronsNerves and Neurons
 Different types of glial cells that provide differentDifferent types of glial cells that provide different
functions for the neuronsfunctions for the neurons
 Neurons send messages through electrical means. IfNeurons send messages through electrical means. If
they touch in the wrong area they will short out. Glialthey touch in the wrong area they will short out. Glial
cells provide protection from this.cells provide protection from this.
 Neurons are found throughout the entire bodyNeurons are found throughout the entire body
 Glial CellsGlial Cells
 Type one-Oligodendrocytes-Produce myelin for brainType one-Oligodendrocytes-Produce myelin for brain
and spinal cordand spinal cord
 Type two-Schwann Cells-Produce myelin for the restType two-Schwann Cells-Produce myelin for the rest
of the bodyof the body
 Myelin covers the axons so they are protected fromMyelin covers the axons so they are protected from
touching each othertouching each other
 The bundled axons are called nervesThe bundled axons are called nerves

 Myelin-Not only protects the nerves, butMyelin-Not only protects the nerves, but
allows the messages to travel fasterallows the messages to travel faster
 Node: Small space that separates theNode: Small space that separates the
axonsaxons
 The message “jumps” the node and movesThe message “jumps” the node and moves
faster because of the myelin sheathfaster because of the myelin sheath
 Multiple Sclerosis is a disease that damagesMultiple Sclerosis is a disease that damages
the myelin sheath so the cells do not functionthe myelin sheath so the cells do not function
or function wellor function well

 Axons of neurons in the body are coatedAxons of neurons in the body are coated
with a thin membrane called thewith a thin membrane called the
neurilemma or Schwann’s membraneneurilemma or Schwann’s membrane
 This is a tunnel that allows damagedThis is a tunnel that allows damaged
nerves to repair themselvesnerves to repair themselves
 This allows severed toes/fingers to repairThis allows severed toes/fingers to repair
themselves when reattachedthemselves when reattached
 The brain and spinal cord do not have thisThe brain and spinal cord do not have this
membrane and therefore cannot repairmembrane and therefore cannot repair
itselfitself

 A neuron that is not firing is electrically chargedA neuron that is not firing is electrically charged
 The outside of the cell has positively chargedThe outside of the cell has positively charged
ions and the inside has negatively charged ionsions and the inside has negatively charged ions
 The cell membrane is semipermeableThe cell membrane is semipermeable
 Substances can easily get into and out of the cellSubstances can easily get into and out of the cell
 Negatively charged ions cannot get out easily so theNegatively charged ions cannot get out easily so the
cell stays negatively charged when at restcell stays negatively charged when at rest
 When at rest the positively charged ions cannot get inWhen at rest the positively charged ions cannot get in
 These opposite charges attract each other and clusterThese opposite charges attract each other and cluster
around the membranearound the membrane

NNeurons and Nerveseurons and Nerves
 Cell is like a baseball stadium (Sodium Ions)Cell is like a baseball stadium (Sodium Ions)
 When the cell is at rest (closed) the positive neuronsWhen the cell is at rest (closed) the positive neurons
(fans) cannot get in. When the cell is stimulated by(fans) cannot get in. When the cell is stimulated by
dendrites the cell membrane opens up the (gates)dendrites the cell membrane opens up the (gates)
one by one and allows the fans in. The electricalone by one and allows the fans in. The electrical
charge moves down the axon causing the positivecharge moves down the axon causing the positive
ions to rush inside reversing the charges on the insideions to rush inside reversing the charges on the inside
and outside of the cellsand outside of the cells
 Resting Potential- When the neuron is not firingResting Potential- When the neuron is not firing
(resting)(resting)
 Action Potential- When the neuron fires causing aAction Potential- When the neuron fires causing a
reversal of the electrical chargereversal of the electrical charge

 When the charge reaches the end of the axonWhen the charge reaches the end of the axon
the charge is transmitted to another cell.the charge is transmitted to another cell.
 To return the cell to a resting stateTo return the cell to a resting state
 The gates close when the action potential has passedThe gates close when the action potential has passed
 The positive ions (fans) get kicked outThe positive ions (fans) get kicked out
 Positive potassium ions also leave the cell making itPositive potassium ions also leave the cell making it
negative fasternegative faster
 The inside is negative and the outside positive soThe inside is negative and the outside positive so
another message can be fired and start the processanother message can be fired and start the process
allover againallover again
 Doors in a hallway (one opens, next opens, firstDoors in a hallway (one opens, next opens, first
closes)closes)

 Some signals cause a neuron to fire,Some signals cause a neuron to fire,
others tell it not to fireothers tell it not to fire
 All or none- neuron either fires completelyAll or none- neuron either fires completely
or does not fire at allor does not fire at all
 Palm of hand examplePalm of hand example

Nerves and Neurons: The SynapseNerves and Neurons: The Synapse
 Axon Terminals- Branches at the end of theAxon Terminals- Branches at the end of the
axonaxon
 Synoptic Knob- Rounded areas on the end ofSynoptic Knob- Rounded areas on the end of
the axon terminalsthe axon terminals
 Synoptic Vesicles-Saclike structure found insideSynoptic Vesicles-Saclike structure found inside
the synaptic knob containing chemicalsthe synaptic knob containing chemicals
 Neurotransmitters- Chemical found in theNeurotransmitters- Chemical found in the
synaptic vesicles that , when released, has ansynaptic vesicles that , when released, has an
effect on the next celleffect on the next cell
 Inside a neuron and will transmit a messageInside a neuron and will transmit a message

 Next to the synoptic knob is anotherNext to the synoptic knob is another
dendrite.dendrite.
 Synapse/Synaptic Gap- fluid-filled spaceSynapse/Synaptic Gap- fluid-filled space
between the synoptic knob and dendritesbetween the synoptic knob and dendrites
or surface of the next cellor surface of the next cell
 The vesicles at the end of axons contain theThe vesicles at the end of axons contain the
molecules of neurotransmittersmolecules of neurotransmitters
Receptor Sites- Locks on the surface ofReceptor Sites- Locks on the surface of
dendritesdendrites
Only allow particular neurotransmitters orOnly allow particular neurotransmitters or
molecules in ( Like a lock and key)molecules in ( Like a lock and key)

 When the action potential reaches the synapticWhen the action potential reaches the synaptic
vesicles they release neurotransmitters into thevesicles they release neurotransmitters into the
synaptic gapsynaptic gap
 The molecules float across the synapse into theThe molecules float across the synapse into the
receptor sites which activates the next cell, thereceptor sites which activates the next cell, the
process continuesprocess continues
 Cells can be turned on and offCells can be turned on and off
 Excitatory Synapse- neurotransmitter causes theExcitatory Synapse- neurotransmitter causes the
receiving cell to firereceiving cell to fire
 Inhibitory Synapse- neurotransmitter causes theInhibitory Synapse- neurotransmitter causes the
receiving cell to stop firingreceiving cell to stop firing

 How drugs affect usHow drugs affect us
 Agonists- mimic or enhance the effects of aAgonists- mimic or enhance the effects of a
neurotransmitter on the receptor sitesneurotransmitter on the receptor sites
increasing/decreasing activityincreasing/decreasing activity
 Antagonists- block or reduce a cell’s responseAntagonists- block or reduce a cell’s response
to the action of other chemicals orto the action of other chemicals or
neurtransmittersneurtransmitters

 NeurotransmittersNeurotransmitters
 Glutamate- Excitatory neurotransmitter thatGlutamate- Excitatory neurotransmitter that
plays a role in learning and developmentplays a role in learning and development
 GABA (y-aminobatyric acid)- InhibitoryGABA (y-aminobatyric acid)- Inhibitory
neurotransmitter that calms, alcohol enhancesneurotransmitter that calms, alcohol enhances
GABAGABA
 Serotonin- Can have excitatory or inhibitorySerotonin- Can have excitatory or inhibitory
effect associated with sleep, mood andeffect associated with sleep, mood and
appetiteappetite
 Low serotonin=depressionLow serotonin=depression

Nerves and Neurotransmitters-Nerves and Neurotransmitters-
 Dopamine- Either excitatory or inhibitoryDopamine- Either excitatory or inhibitory
depending on where in the brain it is releaseddepending on where in the brain it is released
 Too much=SchizophreniaToo much=Schizophrenia
 Too little=Parkinson’s DiseaseToo little=Parkinson’s Disease
Neural Regulators/Neural Peptides- Control the releaseNeural Regulators/Neural Peptides- Control the release
of neurotransmittersof neurotransmitters
Endorphins- When a person is in pain the brain releasesEndorphins- When a person is in pain the brain releases
endorphins to bind with receptors and block the painendorphins to bind with receptors and block the pain
Athletes do not feel pain until after game is overAthletes do not feel pain until after game is over
because of the high levels of endorphins during thebecause of the high levels of endorphins during the
gamegame

 Endorphins and HeroineEndorphins and Heroine
 Heroine is addictive because this drug causesHeroine is addictive because this drug causes
the body to stop producing endorphins. Whenthe body to stop producing endorphins. When
the person is off heroine there are not anythe person is off heroine there are not any
endorphins to block the pain and everythingendorphins to block the pain and everything
hurts so they go back onto the heroine. Thishurts so they go back onto the heroine. This
pain is withdrawl.pain is withdrawl.

Reuptake and EnzymesReuptake and Enzymes
 Neurotransmitters must leave receptorNeurotransmitters must leave receptor
sites so the next stimulation may occursites so the next stimulation may occur
 Reuptake-neurotransmitters are takenReuptake-neurotransmitters are taken
back into the synaptic vesiclesback into the synaptic vesicles
 Cocaine blocks the reuptakeCocaine blocks the reuptake
Acetylcholine is not taken back into vesiclesAcetylcholine is not taken back into vesicles
because it is necessary for muscle functionbecause it is necessary for muscle function
which happens continuouslywhich happens continuously
An enzyme is released to clear the synapseAn enzyme is released to clear the synapse
of acetylcholineof acetylcholine

Reuptake and EnzymesReuptake and Enzymes
 Serotonin- regulates and adjusts moodSerotonin- regulates and adjusts mood
 Some people’s serotonin is not released orSome people’s serotonin is not released or
produced causing depressionproduced causing depression
 Treated with SSRI’s (Selective SerotoninTreated with SSRI’s (Selective Serotonin
Reuptake Inhibitors) Blocks the reuptake ofReuptake Inhibitors) Blocks the reuptake of
serotonin so more is in the synapse to bondserotonin so more is in the synapse to bond
with receptor sites and decrease depressionwith receptor sites and decrease depression

Central Nervous SystemCentral Nervous System
 Central nervous system (CNS)- ConsistsCentral nervous system (CNS)- Consists
of the brain and spinal cordof the brain and spinal cord
 Composed of neurons and glial cells thatComposed of neurons and glial cells that
control life-sustaining functions, thought,control life-sustaining functions, thought,
emotion and behavioremotion and behavior
The BrainThe Brain
Core of the nervous systemCore of the nervous system
Makes sense of the information received fromMakes sense of the information received from
the sensesthe senses
makes decisions, sends commands tomakes decisions, sends commands to
muscles and the rest of the bodymuscles and the rest of the body

 The Spinal CordThe Spinal Cord
 A long bundle of neurons that carriesA long bundle of neurons that carries
messages between the body and the brainmessages between the body and the brain
and is responsible for very fast, lifesavingand is responsible for very fast, lifesaving
reflexesreflexes
 Is divided into two areasIs divided into two areas
 The outer is made of axons and nervesThe outer is made of axons and nerves
 Carries messages from the body up to the brain andCarries messages from the body up to the brain and
from the brain to the bodyfrom the brain to the body
 It is a message pipelineIt is a message pipeline
 The inner is made of cell bodies of neuronsThe inner is made of cell bodies of neurons

 The Reflex ARC in the Spinal CordThe Reflex ARC in the Spinal Cord
 Inside section made of glial cellsInside section made of glial cells
 A primitive “brain”A primitive “brain”
 Responsible for very fast life-saving reflexesResponsible for very fast life-saving reflexes
 Three types of neuronsThree types of neurons
 Afferent (Sensory) Neurons- Carry messages fromAfferent (Sensory) Neurons- Carry messages from
the senses to the spinal cordthe senses to the spinal cord
 Efferent (Motor) Neurons- Carry messages fromEfferent (Motor) Neurons- Carry messages from
the spinal cord to the muscles and glandsthe spinal cord to the muscles and glands
 Interneurons- Connect afferent neurons to efferentInterneurons- Connect afferent neurons to efferent
neuronsneurons
 Make up the inside of the brain and spinal cordMake up the inside of the brain and spinal cord

The Central Nervous SystemThe Central Nervous System
 ExampleExample
 Touch a hot stoveTouch a hot stove
 Afferent neuron will send the pain message up toAfferent neuron will send the pain message up to
the spinal column where it enters into the centralthe spinal column where it enters into the central
area of the spinal cord. The interneuron in thatarea of the spinal cord. The interneuron in that
central area will then receive the message andcentral area will then receive the message and
send out a response along an efferent neuron,send out a response along an efferent neuron,
causing your finger to pull back. If the paincausing your finger to pull back. If the pain
message had to go to the brain more damagemessage had to go to the brain more damage
would be done.would be done.
 Reflex Arc- the connection of the afferent neuronsReflex Arc- the connection of the afferent neurons
to the interneurons to the efferent neuronsto the interneurons to the efferent neurons
resulting in a reflex actionresulting in a reflex action

 AAfferent neuronsfferent neurons aaccess the spinal cordccess the spinal cord
 EEfferent neuronsfferent neurons eexit the spinal cordxit the spinal cord
 When pain message reaches the brainWhen pain message reaches the brain
other reflexes are activatedother reflexes are activated
 Yelling “Ouch!”Yelling “Ouch!”
 Some damage to the central nervous systemSome damage to the central nervous system
can be repairedcan be repaired
 Neuroplasticity- The ability to constantlyNeuroplasticity- The ability to constantly
change both the structure and function ofchange both the structure and function of
many cells in the brain response tomany cells in the brain response to
experience and traumaexperience and trauma

 Nerve implants can be made for the spinalNerve implants can be made for the spinal
cord making the area functionalcord making the area functional
 Neurons in the brain can adapt to performNeurons in the brain can adapt to perform
new functions to replace damaged onesnew functions to replace damaged ones
 Dendrites grow and new synapses areDendrites grow and new synapses are
formed as new information is learnedformed as new information is learned

Stem CellsStem Cells
 Can create other cells such as blood,Can create other cells such as blood,
nerve and brain cellsnerve and brain cells
 Stem cells are retrieved from embryosStem cells are retrieved from embryos
from fertilization clinics and terminatedfrom fertilization clinics and terminated
pregnanciespregnancies
 Stem cells are found in many organs andStem cells are found in many organs and
bone marrowbone marrow
 Nonembryonic stem cells want to becomeNonembryonic stem cells want to become
cells from the areas they were retrievedcells from the areas they were retrieved

The Peripheral Nervous SystemThe Peripheral Nervous System
(PNS)(PNS)
 Made up of all of the nerves and neuronsMade up of all of the nerves and neurons
that are not in the brain and spinal cordthat are not in the brain and spinal cord
 Allows the spinal cord and brain toAllows the spinal cord and brain to
communicate with the rest of the bodycommunicate with the rest of the body
 Two major SystemsTwo major Systems
 Somatic Nervous SystemSomatic Nervous System
 Consists of nerves that carry information from theConsists of nerves that carry information from the
senses to the CNS and from the CNS to thesenses to the CNS and from the CNS to the
voluntary muscles of the bodyvoluntary muscles of the body

Peripheral Nervous SystemPeripheral Nervous System
 Somatic Nervous SystemSomatic Nervous System
 Somatic Pathway- Nerves coming from the sensorySomatic Pathway- Nerves coming from the sensory
organs to the CNS consisting of afferent neuronsorgans to the CNS consisting of afferent neurons
 Motor Pathway- Nerves coming from the CNS to theMotor Pathway- Nerves coming from the CNS to the
voluntary (Skeletal) muscles, consisting of efferentvoluntary (Skeletal) muscles, consisting of efferent
neuronsneurons
 These are the muscles that allow people to move theirThese are the muscles that allow people to move their
bodiesbodies
 These are called voluntary muscles, but can be movedThese are called voluntary muscles, but can be moved
involuntarily as a reflexinvoluntarily as a reflex
 Involuntary muscles (Heart, stomach and intestines, ect)Involuntary muscles (Heart, stomach and intestines, ect)
 Controlled by clumps of neurons located on or near theControlled by clumps of neurons located on or near the
spinal columnspinal column

Autonomic Nervous SystemAutonomic Nervous System
 The functions of this system are basicallyThe functions of this system are basically
automaticautomatic
 Controls the organs, glands, andControls the organs, glands, and
involuntary musclesinvoluntary muscles
 Divided into two systemsDivided into two systems
 The sympathetic DivisionThe sympathetic Division
 Located in the middle of the spinal columnLocated in the middle of the spinal column
 Sympathy with emotionsSympathy with emotions
 Fight or flight responseFight or flight response
 Gets the body ready for stressGets the body ready for stress
 Pupils dilate to see in the dark, heart pumps faster toPupils dilate to see in the dark, heart pumps faster to
draw blood away from nonessential organs, ectdraw blood away from nonessential organs, ect

The Sympathetic DivisionThe Sympathetic Division
 Adrenal glands told to release stress-relatedAdrenal glands told to release stress-related
hormoneshormones
 These only impact certain organs just likeThese only impact certain organs just like
neurotransmitters fit only particular receptor sitesneurotransmitters fit only particular receptor sites
for particular jobsfor particular jobs
 Not all organs are stimulated by the stressNot all organs are stimulated by the stress
hormoneshormones
 Digestion and excretion systems are shut downDigestion and excretion systems are shut down
because they are not needed in times of stressbecause they are not needed in times of stress
 When the stress ends the parasympathetic divisionWhen the stress ends the parasympathetic division
takes overtakes over
 If stress goes on for too long the person may collapseIf stress goes on for too long the person may collapse

The Parasympathetic DivisionThe Parasympathetic Division
 The eat, drink and rest systemThe eat, drink and rest system
 Located on top and bottom of spinalLocated on top and bottom of spinal
columncolumn
 Para means beyond or next toPara means beyond or next to
 Job is to restore the body to it’s normalJob is to restore the body to it’s normal
function after a stressful eventfunction after a stressful event
 Responsible for most of the body’s regularResponsible for most of the body’s regular
functioningfunctioning

Inside the BrainInside the Brain
 Clinical StudiesClinical Studies
 Animal studiesAnimal studies
 Electrically stimulate areas of the brain and see theElectrically stimulate areas of the brain and see the
resultsresults
 Deep Lesioning- A thin wire is inserted into theDeep Lesioning- A thin wire is inserted into the
brain and an electrical current is sent to destroybrain and an electrical current is sent to destroy
the neurons that are at the tip of the wire.the neurons that are at the tip of the wire.
 Shallow Lesioning- Lesioning done at the surfaceShallow Lesioning- Lesioning done at the surface
 Electrical stimulation of the brain (ESB)- weakElectrical stimulation of the brain (ESB)- weak
electric current sent to cause stimulation and aelectric current sent to cause stimulation and a
reactionreaction

Inside the BrainInside the Brain
 Human studiesHuman studies
 Cannot damage the brain on purpose forCannot damage the brain on purpose for
study so they study those that are alreadystudy so they study those that are already
damageddamaged
 However, no two damaged brains are at the sameHowever, no two damaged brains are at the same
extentextent

EEGEEG
 Electrocephalograph- Electrodes are placed onElectrocephalograph- Electrodes are placed on
the skin of the skullthe skin of the skull
 The wires are connected to a computerThe wires are connected to a computer
 Can indicate stages of sleep, seizures andCan indicate stages of sleep, seizures and
tumors as well as activity during reading, writingtumors as well as activity during reading, writing
and speakingand speaking
 BETA waves- indicate waking activity-fastBETA waves- indicate waking activity-fast
irregular wavesirregular waves
 ALPHA waves- indicate relaxation-slow regularALPHA waves- indicate relaxation-slow regular
waveswaves
 THETA waves- Indicate drowsiness and sleepTHETA waves- Indicate drowsiness and sleep
 DELTA waves- Indicate a deep stage of sleep-DELTA waves- Indicate a deep stage of sleep-
slow large wavesslow large waves

EEGEEG
 Independent Component Analysis (ICA)-Independent Component Analysis (ICA)-
Detailed interpretation of the signalsDetailed interpretation of the signals
coming from the different areas of thecoming from the different areas of the
brainbrain
 Event-related potential (ERP)- The resultsEvent-related potential (ERP)- The results
of multiple readings and average theof multiple readings and average the
resultsresults

CT ScansCT Scans
 CT (Computed Tomography) meansCT (Computed Tomography) means
mapping slicesmapping slices
 X-rays used to look at the inside of theX-rays used to look at the inside of the
brainbrain
 Shows stroke damage, tumors, injuriesShows stroke damage, tumors, injuries
and abnormal brain structureand abnormal brain structure
 Shows the structure of the brainShows the structure of the brain

MRI ScansMRI Scans
 MRI (Magnetic Resonance Imaging)MRI (Magnetic Resonance Imaging)
shows much more detail inside the brainshows much more detail inside the brain
 Magnetic field is used to show a 3Magnetic field is used to show a 3
dimensional pix of the brain and evendimensional pix of the brain and even
displays “slices” of itdisplays “slices” of it
 Shows the structure of the brainShows the structure of the brain

PET ScansPET Scans
 PET (Positron emission tomography)-Shows thePET (Positron emission tomography)-Shows the
brain workingbrain working
 Injected with a radioactive glucose (Sugar)Injected with a radioactive glucose (Sugar)
 The cells that take up the glucose are activeThe cells that take up the glucose are active
 Colors show levels of activityColors show levels of activity
 Can have a person perform tasks to see whichCan have a person perform tasks to see which
parts of the brain are activeparts of the brain are active

Functional MRI (fMRI)Functional MRI (fMRI)
 Tracks the levels of oxygen and whereTracks the levels of oxygen and where
they go to see what areas are activethey go to see what areas are active
 Give more detail, are clearer than PETGive more detail, are clearer than PET
scansscans

Structure of the BrainStructure of the Brain
 The HindbrainThe Hindbrain
 Medulla means marrow or inner substanceMedulla means marrow or inner substance
 Located at the top of the spinal columnLocated at the top of the spinal column
 Part of the brain that controls heartbeat, breathingPart of the brain that controls heartbeat, breathing
and swallowingand swallowing
 This is where Christopher Reeves was hurt when he fell off aThis is where Christopher Reeves was hurt when he fell off a
horse. He became paralyzed and could not breath on hishorse. He became paralyzed and could not breath on his
ownown
 This is where the nerves for the left side of the body cross toThis is where the nerves for the left side of the body cross to
the right side of the brain and vice versathe right side of the brain and vice versa

Structure of the BrainStructure of the Brain
 Pons means bridgePons means bridge
 Connects the lower parts of the brain with theConnects the lower parts of the brain with the
upper partsupper parts
 Above the medullaAbove the medulla
 This is where the motor nerves carryThis is where the motor nerves carry
messages to the bodymessages to the body
 Helps to coordinate the left side with the rightHelps to coordinate the left side with the right
side in movementsside in movements
 Influences sleep, dreaming and arousalInfluences sleep, dreaming and arousal

Reticular Formation (RF)Reticular Formation (RF)
 Where the neurons run through the middle of theWhere the neurons run through the middle of the
pons and medullapons and medulla
 Area allows a person to pay attention to pertinentArea allows a person to pay attention to pertinent
informationinformation
 Allows a person to ignore white noiseAllows a person to ignore white noise
 Helps keep people alert and arousedHelps keep people alert and aroused
 Reticular Activating System (RAS)-stimulates theReticular Activating System (RAS)-stimulates the
upper part of the brain keeping the person awake andupper part of the brain keeping the person awake and
alertalert
 Come to full attention when a car pulls in front of youCome to full attention when a car pulls in front of you
 Mother hears only the crying baby and can ignore otherMother hears only the crying baby and can ignore other
noisesnoises
 May be involved in ADHDMay be involved in ADHD

Reticular FormationReticular Formation
 If the RF is stimulated in rats theyIf the RF is stimulated in rats they
immediately awakenimmediately awaken
 If it is damaged they go into a permanentIf it is damaged they go into a permanent
comacoma

CerebellumCerebellum
 Means little brainMeans little brain
 Part of the lower brain that controlsPart of the lower brain that controls
involuntary, rapid, fine motor movementinvoluntary, rapid, fine motor movement
 Learned reflexes, skills and habits areLearned reflexes, skills and habits are
stored here so they become automaticstored here so they become automatic
 Allows people to not have to think aboutAllows people to not have to think about
posture, muscle tone and balanceposture, muscle tone and balance
 May use skills like skating, dancing playMay use skills like skating, dancing play
musicmusic
 If this is damaged the person becomesIf this is damaged the person becomes

CerebellumCerebellum
 Spinocerebellar DegenerationSpinocerebellar Degeneration
 Disease in which the symptoms are tremors,Disease in which the symptoms are tremors,
unsteady walk, slurred speech, dizziness andunsteady walk, slurred speech, dizziness and
muscle weaknessmuscle weakness
 Eventually looses all coordinationEventually looses all coordination
 Similar to a intoxicated personSimilar to a intoxicated person

Structures under the CortexStructures under the Cortex
 Cortex-The outer wrinkled covering of theCortex-The outer wrinkled covering of the
brainbrain
 Limbic SystemLimbic System
 Includes the thalamus, hypothalamus,Includes the thalamus, hypothalamus,
hippocampus and amygdalahippocampus and amygdala
 Involved in emotions, motivation and learningInvolved in emotions, motivation and learning

Limbic SystemLimbic System
 Thalamus (inner chamber)Thalamus (inner chamber)
 Relays sensory information from the lower part of theRelays sensory information from the lower part of the
brain to the proper areas of the cortex and processesbrain to the proper areas of the cortex and processes
some sensory information before sending it to itssome sensory information before sending it to its
proper areaproper area
 Damage to this area may lead to partial or total loss toDamage to this area may lead to partial or total loss to
any or all of these sensesany or all of these senses
 Olfactory bulbs-two projections under the front of theOlfactory bulbs-two projections under the front of the
brain that receive information from the receptors inbrain that receive information from the receptors in
the nosethe nose
 This is the only sense that is not affected by damage to theThis is the only sense that is not affected by damage to the
thalamusthalamus

 Hypothalamus (below the inner chamber)Hypothalamus (below the inner chamber)
 Responsible for motivational behavior such asResponsible for motivational behavior such as
sleep, hunger, thirst and sexsleep, hunger, thirst and sex
 Regulates temperatureRegulates temperature
 Controls the pituitary glandControls the pituitary gland
 Pituitary Gland “Master Gland”- Controls thePituitary Gland “Master Gland”- Controls the
functions of all other endocrine glandsfunctions of all other endocrine glands

 Hippocampus- located within eachHippocampus- located within each
temporal lobe and is responsible for thetemporal lobe and is responsible for the
formation of long-term memory and theformation of long-term memory and the
storage of memory of the location ofstorage of memory of the location of
objectsobjects
 Acetylcholine is a neurotransmitter that isAcetylcholine is a neurotransmitter that is
involved in memory functioninvolved in memory function

 Amygdala (Almond)- Responsible for fearAmygdala (Almond)- Responsible for fear
responses and memory of fearresponses and memory of fear
 Information from the senses goes throughInformation from the senses goes through
here before going to the upper part of thehere before going to the upper part of the
brain so the response can be quickbrain so the response can be quick
 Damage to this area leads to a lack of fearDamage to this area leads to a lack of fear

 The CortexThe Cortex
 Outermost part of the brainOutermost part of the brain
 Made of tightly packed neuronsMade of tightly packed neurons
 This is so wrinkly to allow for more area toThis is so wrinkly to allow for more area to
exist within the skullexist within the skull
 Corticalization- The cortex starts out smooth,Corticalization- The cortex starts out smooth,
but gains wrinkles as it becomes morebut gains wrinkles as it becomes more
complex and increases in sizecomplex and increases in size
 This is the actual measure of intelligenceThis is the actual measure of intelligence

Cortex and the LobesCortex and the Lobes
 Cortex is divided into two sections calledCortex is divided into two sections called
Cerebral Hemispheres which areCerebral Hemispheres which are
connected by the Corpus Callosumconnected by the Corpus Callosum
 Corpus Callosum allows the twoCorpus Callosum allows the two
hemispheres to communicatehemispheres to communicate
 Each hemisphere can be divided into fourEach hemisphere can be divided into four
sectionssections

Cortex and the lobesCortex and the lobes
 Occipital Lobes (Rear of the head)-Occipital Lobes (Rear of the head)-
Processes visual information in theProcesses visual information in the
primary visual cortexprimary visual cortex
 Any stimulation to the area at the back ofAny stimulation to the area at the back of
the head processes vision, so when youthe head processes vision, so when you
get hit back there you “see stars”get hit back there you “see stars”

Parietal Lobes (Wall)- Located at top ofParietal Lobes (Wall)- Located at top of
each hemisphere that contains the centerseach hemisphere that contains the centers
for touch, taste and temperaturefor touch, taste and temperature
sensationssensations
Somatosensory Cortex- Area of neuronsSomatosensory Cortex- Area of neurons
running down the front of the parietalrunning down the front of the parietal
lobes responsible for processinglobes responsible for processing
information from the skin and internal bodyinformation from the skin and internal body
receptors for touch, temperature, bodyreceptors for touch, temperature, body
position and possibly tasteposition and possibly taste
The cells at the top receive info fromThe cells at the top receive info from
the bottom of the body and vice versathe bottom of the body and vice versa

 Temporal Lobes (of or near the temples)-Temporal Lobes (of or near the temples)-
Located just behind the temples, containLocated just behind the temples, contain
the Primary auditory cortex and Auditorythe Primary auditory cortex and Auditory
association areaassociation area
 When hit in the side of the head, may hear aWhen hit in the side of the head, may hear a
ringing soundringing sound
 This area also deals with language and tasteThis area also deals with language and taste

 Frontal Lobes- Located at the front of theFrontal Lobes- Located at the front of the
brain, this is where higher functioning ofbrain, this is where higher functioning of
the brain is performed such as planning,the brain is performed such as planning,
personality, memory storage, complexpersonality, memory storage, complex
decision making and language also helpsdecision making and language also helps
with emotionswith emotions
 Damage to this area may cause a personDamage to this area may cause a person
to become “stuck” on one step of a task orto become “stuck” on one step of a task or
repeat the wrong answer over and overrepeat the wrong answer over and over

 Frontal LobesFrontal Lobes
 Motor Cortex- area in back of frontal lobe thatMotor Cortex- area in back of frontal lobe that
sends motor commands to the muscles of thesends motor commands to the muscles of the
somatic nervous systemsomatic nervous system

Association areas of the CortexAssociation areas of the Cortex
 Association areas- areas within each lobe of theAssociation areas- areas within each lobe of the
cortex responsible for making connectionscortex responsible for making connections
between the sensory information coming into thebetween the sensory information coming into the
brain and stored memories, images, andbrain and stored memories, images, and
knowledgeknowledge
 This area makes sense of the sensory informationThis area makes sense of the sensory information
that is receivedthat is received
 Broca’s Area- Allows a person to speakBroca’s Area- Allows a person to speak
smoothly and fluentlysmoothly and fluently
 Broca’s Aphasia-Damage to this area makes it hardBroca’s Aphasia-Damage to this area makes it hard
for the person to speak in a smooth, orderly fashionfor the person to speak in a smooth, orderly fashion
 May mispronounce words, they cannot control theirMay mispronounce words, they cannot control their
pronunciation of the words (not a stutter)pronunciation of the words (not a stutter)
 ““I lov…..eat…….muchI lov…..eat…….much

Association areas of the CortexAssociation areas of the Cortex
 Wernicke’s Area- Area of brain associatedWernicke’s Area- Area of brain associated
with understanding the meanings of wordswith understanding the meanings of words
 Wernicke’s Aphasia- Damage to theWernicke’s Aphasia- Damage to the
Wernicke’s area that causes a person toWernicke’s area that causes a person to
not understand or produce meaningfulnot understand or produce meaningful
languagelanguage
 ““Oh that’s so Saturday hard.”Oh that’s so Saturday hard.”
 ““Get me some milk out of the air conditioner!”Get me some milk out of the air conditioner!”

Spatial NeglectSpatial Neglect
 Spatial neglect- Damage in theSpatial neglect- Damage in the
association areas of the right side of brainassociation areas of the right side of brain
which prevents the person fromwhich prevents the person from
recognizing objects on the left side ofrecognizing objects on the left side of
vision or bodyvision or body
 Left side will be recognized if specificallyLeft side will be recognized if specifically
called attention to itcalled attention to it
 Make-up and mirror examples pgs. 76-77Make-up and mirror examples pgs. 76-77

The Cerebral HemispheresThe Cerebral Hemispheres
 Cerebrum- Upper part of brain consisting of twoCerebrum- Upper part of brain consisting of two
hemispheres with structures connecting themhemispheres with structures connecting them
 Split-Brain researchSplit-Brain research
 Each side of the brain has it’s own specializationsEach side of the brain has it’s own specializations
 Corpus Callosum was cut disconnecting the twoCorpus Callosum was cut disconnecting the two
halves of the brainhalves of the brain
 Showed objects to one side of person and if onShowed objects to one side of person and if on
right could identify the object, if on left could notright could identify the object, if on left could not
verbally identify the object or be certain they sawverbally identify the object or be certain they saw
anythinganything
 If left hand was used they could verbally state, butIf left hand was used they could verbally state, but
not seenot see

Cerebral HemispheresCerebral Hemispheres
 Left sideLeft side
 Language, speech, handwriting, calculations,Language, speech, handwriting, calculations,
sense of time, rhythm and any thoughtsense of time, rhythm and any thought
analysisanalysis
 Can break information down into small partsCan break information down into small parts
for interpretationfor interpretation
 RightRight
 Perception, visualization, spatial perception,Perception, visualization, spatial perception,
recognition of patterns, faces, emotions, melodiesrecognition of patterns, faces, emotions, melodies
and expression of emotionsand expression of emotions
 Also comprehends simple languageAlso comprehends simple language
 Can process information all at onceCan process information all at once

Cerebral HemispheresCerebral Hemispheres
 Most right-handed people also have theirMost right-handed people also have their
left hemisphere in control of their otherleft hemisphere in control of their other
fine motor skills, such as speech, a fewfine motor skills, such as speech, a few
right-handers actually have their languageright-handers actually have their language
functions in the right hemispherefunctions in the right hemisphere

The Endocrine GlandsThe Endocrine Glands
 Some glands do not secrete chemicalsSome glands do not secrete chemicals
that affect behavior; sweat and salivarythat affect behavior; sweat and salivary
 Endocrine glands- do not have ducts andEndocrine glands- do not have ducts and
secrete chemicals into bloodstreamsecrete chemicals into bloodstream
 These chemicals are hormonesThese chemicals are hormones
 The hormones are carried in the bloodstreamThe hormones are carried in the bloodstream
to the organ they are meant to impactto the organ they are meant to impact
 The molecules of the hormones fit into theThe molecules of the hormones fit into the
receptor sites of the organs and influencereceptor sites of the organs and influence
behaviorbehavior

The Pituitary GlandThe Pituitary Gland
 Pituitary gland- secretes human growthPituitary gland- secretes human growth
hormone (HGH) and influences all of thehormone (HGH) and influences all of the
other hormone secreting glandsother hormone secreting glands
 AKA the Master GlandAKA the Master Gland
 HGH impacts a child’s size as he/she growsHGH impacts a child’s size as he/she grows
 Is an important part of communicationIs an important part of communication
between the organs, hypothalamus and otherbetween the organs, hypothalamus and other
glandsglands

 Pineal gland- Secretes melatonin whichPineal gland- Secretes melatonin which
regulates the sleep-wake cycleregulates the sleep-wake cycle
 Thyroid gland- Secretes thyroxin whichThyroid gland- Secretes thyroxin which
regulates metabolismregulates metabolism
 Pancreas- Controls the level of sugar inPancreas- Controls the level of sugar in
the blood by secreting insulin andthe blood by secreting insulin and
glucagonsglucagons
 Too little insulin=diabetes, Too muchToo little insulin=diabetes, Too much
insulin=hypoglycemia-hunger all of the timeinsulin=hypoglycemia-hunger all of the time

 The Gonads- sex glands including ovariesThe Gonads- sex glands including ovaries
and testesand testes
 Secrete hormones that regulate sexualSecrete hormones that regulate sexual
behavior and reproductionbehavior and reproduction
 Does not control all sexual behaviorDoes not control all sexual behavior
 The brain is the master controller of sexualThe brain is the master controller of sexual
behavior like psychological factors such asbehavior like psychological factors such as
attractivenessattractiveness

The Adrenal GlandsThe Adrenal Glands
 Both are located on top of the kidneysBoth are located on top of the kidneys
 Each one is divided into two sectionsEach one is divided into two sections
 Adrenal medulla-releases ephinephrine andAdrenal medulla-releases ephinephrine and
norepinephrine which are released in times ofnorepinephrine which are released in times of
stress and aids in sympathystress and aids in sympathy

The Adrenal GlandsThe Adrenal Glands
 Adrenal cortex- produces corticoids whatAdrenal cortex- produces corticoids what
regulate salt intake, initiate and control stressregulate salt intake, initiate and control stress
reactions, and provide sex hormones inreactions, and provide sex hormones in
addition to the gonadsaddition to the gonads
 Cortisol-released during times of stressCortisol-released during times of stress
 Influences the release of glucose into theInfluences the release of glucose into the
bloodstream to give energy to the brain andbloodstream to give energy to the brain and
fatty acids to the muscles for energyfatty acids to the muscles for energy

Mirror NeuronsMirror Neurons
 Neurons that fire when doing an actionNeurons that fire when doing an action
also fire when seeing that actionalso fire when seeing that action
preformedpreformed
 Wince when see someone get hurtWince when see someone get hurt
 Smile when see someone else smileSmile when see someone else smile
 A stroke patient may be able to relearn aA stroke patient may be able to relearn a
behavior if he/she sees it done by someonebehavior if he/she sees it done by someone
elseelse

Mirror Neurons and AutismMirror Neurons and Autism
 Mirror neurons are a part ofMirror neurons are a part of
communication and socializationcommunication and socialization
 People with autismPeople with autism
 The mirror neurons to not fire when seeingThe mirror neurons to not fire when seeing
others doing a behaviorothers doing a behavior
 Malfunctioning mirror neurons may be theMalfunctioning mirror neurons may be the
cause of autismcause of autism
 In a bad mood/depressed=watch a comedy?In a bad mood/depressed=watch a comedy?

Chapter 2 biological perspective notes

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