I. The Nervous SystemI. The Nervous System

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Nervous System Nervous System [p116][p116]

Gathers and processes informationGathers and processes information Produces responses to stimuliProduces responses to stimuli Coordinates workings of different Coordinates workings of different

cellscells Consists of 2 parts:Consists of 2 parts:

– Central nervous system (CNS)Central nervous system (CNS)– Peripheral nervous system (PNS)Peripheral nervous system (PNS)

Organization of the Organization of the nervous systemnervous system[pp116-119][pp116-119]

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The Central Nervous The Central Nervous System System [pp116-117][pp116-117]BrainBrain•Housed in the skullHoused in the skull•Approx. 3 lbsApprox. 3 lbs•Mostly comprised of neuronsMostly comprised of neuronsSpinal cordSpinal cord•Comprised of neurons and Comprised of neurons and

supportive tissuesupportive tissue•Runs from base of brain down Runs from base of brain down

center of backcenter of back•Protected by spinal columnProtected by spinal column

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The Peripheral Nervous The Peripheral Nervous System System [pp117-118][pp117-118]

Somatic Nervous SystemSomatic Nervous System*Controls skeletal muscles*Controls skeletal muscles*Allows for voluntary movement*Allows for voluntary movementAutonomic Nervous SystemAutonomic Nervous System*Controls muscles of internal *Controls muscles of internal organsorgans*Regulates blood vessels, glands, *Regulates blood vessels, glands, internal organsinternal organs*Divided into 2 systems:*Divided into 2 systems:

•Sympathetic Nervous SystemSympathetic Nervous System•Parasympathetic Nervous SysParasympathetic Nervous Sys

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The Autonomic Nervous The Autonomic Nervous System System [p118][p118]Sympathetic Nervous Sympathetic Nervous SystemSystem*Arouses the body*Arouses the body*Uses energy*Uses energy*”Fight or flight” response*”Fight or flight” responseParasympathetic Nervous Parasympathetic Nervous SystemSystem*Calms the body*Calms the body*Conserves energy*Conserves energy

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Sympathetic nervous Sympathetic nervous system:system:

Parasympathetic Parasympathetic nervous system:nervous system:

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Biofeedback Biofeedback [p118][p118]

A method for gaining control over A method for gaining control over the autonomic nervous systemthe autonomic nervous system

One learns using feedback from One learns using feedback from equipment that measures equipment that measures biological functions (e.g., body biological functions (e.g., body temperature, blood pressure, temperature, blood pressure, sweat response, muscle tension, sweat response, muscle tension, brain activity)brain activity)

II. Neural CommunicationII. Neural Communication

Nervous system Nervous system [p119][p119]

The body’s The body’s electroelectrochemical chemical communication circuitrycommunication circuitry

Made up of:Made up of:– nerve cellsnerve cells ( (neuronsneurons)—conduct )—conduct

impulsesimpulses– and and glial cellsglial cells ( (gliaglia)—support cells)—support cells

Structure of a neuron—Structure of a neuron—3 main parts 3 main parts [p120][p120]

Cell body: Cell body: Keeps neuron Keeps neuron alive and determines whether alive and determines whether it will fireit will fire

Dendrites: Dendrites: Receive Receive information from other information from other neurons and transmit toward neurons and transmit toward the cell bodythe cell body

Axon: Axon: Extending fiber that Extending fiber that conducts impulses away from conducts impulses away from the cell body to other cellsthe cell body to other cells

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How neurons How neurons communicatecommunicate

Axon terminals release Axon terminals release neurotransmitterneurotransmitter

Neurotransmitter Neurotransmitter enters enters synapsesynapse ( (gap gap between neuronsbetween neurons) ) [p122][p122]

Neurotransmitter binds Neurotransmitter binds to receptors that it fitsto receptors that it fits

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Neurotransmitter Neurotransmitter [p125][p125]

Chemical Chemical released by a released by a transmitting transmitting neuron at the neuron at the synapse and synapse and capable of capable of affecting the affecting the activity of a activity of a receiving neuronreceiving neuron

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III. A tour through the III. A tour through the brainbrain

The brain stemThe brain stem

MedullaMedullaResponsible for certain Responsible for certain automatic functions such as automatic functions such as breathing and heart ratebreathing and heart rate [p130][p130]PonsPonsInvolved in sleeping, waking, Involved in sleeping, waking, and dreaming and dreaming [p130][p130]Reticular activating Reticular activating systemsystemArouses cortex and screens Arouses cortex and screens incoming information incoming information [p131][p131]

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The cerebellum The cerebellum [p131][p131]

Regulates movement Regulates movement and balanceand balance

Involved in Involved in remembering simple remembering simple skills and acquired skills and acquired reflexesreflexes

Plays a part in:Plays a part in:•Analyzing sensory infoAnalyzing sensory info•Solving problemsSolving problems•Understanding wordsUnderstanding words

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The thalamusThe thalamus

Relays sensory Relays sensory messages to the messages to the cerebral cortexcerebral cortex

Includes all sensory Includes all sensory messages except messages except those from olfactory those from olfactory bulbbulb

[p131][p131]

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The limbic system The limbic system [p132][p132]

A group of brain areas A group of brain areas involved in emotional involved in emotional reactions and reactions and motivated behaviormotivated behavior

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The amygdala The amygdala [p132][p132]

Responsible forResponsible for

•ArousalArousal

•Regulation of emotionRegulation of emotion

•Initial emotional Initial emotional

response to sensory response to sensory

informationinformation

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HypothalamusHypothalamus[p131][p131]

•Involved in:Involved in:•EmotionsEmotions•Drives vital to survivalDrives vital to survival

• FearFear

• HungerHunger

• ThirstThirst

• ReproductionReproduction

•Feeling rewardedFeeling rewarded

•Regulating autonomic nervousRegulating autonomic nervous

systemsystem

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Pituitary glandPituitary gland[p132][p132]

• Small endocrine gland which releases Small endocrine gland which releases hormones and regulates other hormones and regulates other endocrine glandsendocrine glands

• Works in conjunction with Works in conjunction with hypothalamushypothalamus

The endocrine system The endocrine system [p126][p126]

Endocrine Endocrine glands release glands release hormones into hormones into the the bloodstream…bloodstream…

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…Hormones regulate growth, metabolism, sexual development and behavior, and other functions.

The hippocampusThe hippocampus[pp132-133][pp132-133]Responsible for storage of Responsible for storage of new information in memorynew information in memory

Compares sensory Compares sensory information with what the information with what the brain expects about the brain expects about the worldworld

Enables us to form spatial Enables us to form spatial memories for navigating the memories for navigating the environmentenvironment

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The cerebrumThe cerebrum[p133][p133]

•Largest brain structureLargest brain structure

•In charge of most sensory, motor, and In charge of most sensory, motor, and cognitive processescognitive processes

•Divided into two halves, called Divided into two halves, called hemisphereshemispheres

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Lobes of the cerebral Lobes of the cerebral cortex (cerebrum) cortex (cerebrum) [p134][p134]Occipital lobesOccipital lobesVision (visual cortex)Vision (visual cortex)Parietal lobesParietal lobes Body sensationBody sensation(somatosensory cortex)(somatosensory cortex)Temporal lobesTemporal lobesMemory, perception, emotion, Memory, perception, emotion, hearing (auditory cortex)hearing (auditory cortex)Frontal lobesFrontal lobesEmotion, planning, creative thinking, Emotion, planning, creative thinking, personality, and movement (motor cortex)personality, and movement (motor cortex)

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Phineas Gage’s frontal Phineas Gage’s frontal lobe damage lobe damage [pp134-135][pp134-135]

Gage was a railroad Gage was a railroad construction foremanconstruction foreman

An 1848 explosion An 1848 explosion forced a steel tamping forced a steel tamping rod through his headrod through his head

Others said he was Others said he was “no longer Gage”“no longer Gage”

Lost his job, worked Lost his job, worked as a sideshow exhibitas a sideshow exhibit

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The corpus callosum The corpus callosum [p133][p133]

Millions of myelinated axons Millions of myelinated axons connecting the brain’s connecting the brain’s hemisphereshemispheres

Provides a pathway for Provides a pathway for communicationcommunication

If surgically severed to treat If surgically severed to treat epilepsy, resulting in a epilepsy, resulting in a ““split-brainsplit-brain” condition, the ” condition, the hemispheres cannot hemispheres cannot communicate directly communicate directly [p137][p137]

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Lateralization [Lateralization [p133]p133]

Specialization Specialization of the two of the two cerebral cerebral hemispheres hemispheres for particular for particular operationsoperations

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Motor control and the Motor control and the hemisphereshemispheres Left hemisphere Left hemisphere

controls right controls right side of bodyside of body

Right hemisphere Right hemisphere controls left side controls left side of bodyof body

Broca’s areaBroca’s area

Left hemisphere Left hemisphere controls speech controls speech production (in production (in Broca’s area) Broca’s area) [p134][p134]

What is the object in your What is the object in your left hand?left hand?

If someone with a If someone with a split brain is split brain is blindfolded and blindfolded and asked what they asked what they are holding in are holding in their left hand, their left hand, can they do it?can they do it?

Plasticity Plasticity [p123][p123]

•The brain’s ability to change and adapt in The brain’s ability to change and adapt in response to experienceresponse to experience•Reorganizing or growing new neural Reorganizing or growing new neural connectionsconnections

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IV. Techniques for IV. Techniques for looking into the brainlooking into the brain

NeurosurgeryNeurosurgery

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Electroencephalogram Electroencephalogram (EEG) (EEG) [p128][p128]

A recording of neural activity detected A recording of neural activity detected by electrodesby electrodes

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Positron Emission Positron Emission Tomography (PET Scan) Tomography (PET Scan) [p129][p129]

Active areas have increased Active areas have increased blood flow.blood flow.

Sensors detect radioactivity.Sensors detect radioactivity.

Different tasks show distinct Different tasks show distinct activity patterns.activity patterns.

A method for analyzing biochemical activity in the A method for analyzing biochemical activity in the brain, using injections of a glucose-like substance brain, using injections of a glucose-like substance containing a radioactive elementcontaining a radioactive element

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Magnetic Resonance Imaging Magnetic Resonance Imaging (MRI) (MRI) [p129][p129]

Magnetic fields align certain Magnetic fields align certain ions and compounds.ions and compounds.

When field is removed, these When field is removed, these molecules release energy as molecules release energy as radio waves.radio waves.

Computer calculates tissue Computer calculates tissue density from radio waves.density from radio waves.

Provides clear 3D imagesProvides clear 3D images

Method for studying body and brain tissueMethod for studying body and brain tissue

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Your turnYour turn

Jenny bumps her head and is suddenly unable Jenny bumps her head and is suddenly unable to see, although the doctor says there is to see, although the doctor says there is nothing wrong with her eyes? Which part of nothing wrong with her eyes? Which part of her brain did Jenny damage?her brain did Jenny damage?

1. The amygdala1. The amygdala

2. The hippocampus2. The hippocampus

3. The occipital lobe of the cerebral cortex3. The occipital lobe of the cerebral cortex

4. The parietal lobe of the cerebral cortex4. The parietal lobe of the cerebral cortex

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Your turnYour turn

Jenny bumps her head and is suddenly unable Jenny bumps her head and is suddenly unable to see, although the doctor says there is to see, although the doctor says there is nothing wrong with her eyes? Which part of nothing wrong with her eyes? Which part of her brain did Jenny damage?her brain did Jenny damage?

1. The amygdala1. The amygdala

2. The hippocampus2. The hippocampus

3. The occipital lobe of the cerebral cortex3. The occipital lobe of the cerebral cortex

4. The parietal lobe of the cerebral cortex4. The parietal lobe of the cerebral cortex

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