Biology128_NervousSystemI

8/4/2019 Biology128_NervousSystemI

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Chapter 8-Nervous System


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Motor Control? Epilepsy, Phantom limb, deepbrain stim

Movie : Introduction to the Nervous System

Functions of the Nervous System:

Detect the Environment (Sensory)

Integrate Information (ControlCenter)

Maintain homeostasis (Control Center)

Control muscles and glands (Effector)

Mental activity: thinking, feeling,

remembering, learning (Effector)

Deep Brain Stim for Parkinsons: http://www.youtube.com/watch?v=QFtgV1vqwiE and Alzheimersbrain tutorial: http://www.alz.org/alzheimers_disease_4719.aspLife without pain receptors: http://www.uth.tmc.edu/nba/neuroscience/s2/ii6-1.html

Phantom Limb Pain: http://www.ted.com/index.php/speakers/vilayanur_ramachandran.html
http://howneuronswork.mpg/http://www.youtube.com/watch?v=QFtgV1vqwiEhttp://www.alz.org/alzheimers_disease_4719.asphttp://www.uth.tmc.edu/nba/neuroscience/s2/ii6-1.htmlhttp://www.ted.com/index.php/speakers/vilayanur_ramachandran.htmlhttp://www.ted.com/index.php/speakers/vilayanur_ramachandran.htmlhttp://www.uth.tmc.edu/nba/neuroscience/s2/ii6-1.htmlhttp://www.uth.tmc.edu/nba/neuroscience/s2/ii6-1.htmlhttp://www.uth.tmc.edu/nba/neuroscience/s2/ii6-1.htmlhttp://www.alz.org/alzheimers_disease_4719.asphttp://www.youtube.com/watch?v=QFtgV1vqwiEhttp://howneuronswork.mpg/http://howneuronswork.mpg/


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Divisions of the Nervous System

3

SensoryMotor


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Nervous SystemNervous system is divided in 2 main parts:

Central Nervous System (CNS): brain & spinal cordPeripheral Nervous System (PNS): nerves to and from the CNS


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Brain and Spinal Cord are protected by bone andconnective tissue meninges. Both float and arecushioned by cerebrospinal fluid (CSF)

5


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Protective Covering: Skull andMeninges

Dura mater consists of an outerperiosteal layer and an inner(meningeal layer) In a few places, between

the layers there are duralsinuses

Dural septa (flat partitions) Falx cerebri Falx cerebelli Tentorium cereblli

Arachnoid mater covers thesurface of the brain and hasCSF - filled subarachnoid space(with blood vessels)

Pia mater is anchored to thebrain (penetrates sulci)


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Arachnoid villus

Superior

sagittal sinus Pia matter Subarachnoid space

Meningeallayer

Periosteallayer

Arachnoid


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9


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1010


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11

http://neurosurgery.seattlechildrens.org/conditions_treated/hydrocephalus.asp
http://neurosurgery.seattlechildrens.org/conditions_treated/hydrocephalus.asphttp://neurosurgery.seattlechildrens.org/conditions_treated/hydrocephalus.asphttp://neurosurgery.seattlechildrens.org/conditions_treated/hydrocephalus.asphttp://neurosurgery.seattlechildrens.org/conditions_treated/hydrocephalus.asphttp://neurosurgery.seattlechildrens.org/conditions_treated/hydrocephalus.asp


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The Central Nervous System

Surface anatomy

includes cerebralhemispheres,cerebellum, brain stem(midbrain, pons,medulla) and spinal cord

Contains almost 98% ofthe bodys nervoustissue: 1010 to 1011 neurons (10%) 1013 glia (90%)

Trillions of connectionsbetween neurons

Cortical regions havedifferent processingfunctions


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Motor

Motivation

Aggression

Mood

Planning

ProcessesSensory

Visual

Hearing

Learning Memory

Visual -spatial

cognition


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Fifth Lobe: Insula

UnderstandingSpeech

Taste

Cravings


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Introduction to Functional Regions of Brain:Left half of the brain controls the right side of body (sensory and motor)Some functions are lateralized (e.g. language is on the left in most people)


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Reference: http://members.shaw.ca/hidden-talents/brain/jpg/b-right.jpg and http://hiddentalents.org/index.htm

Introduction to Functional Regions of BrainRight half of the brain controls the left side of body (sensory and motor)Some functions are lateralized (e.g. visual - spatial tasks are on the right in most people)
http://members.shaw.ca/hidden-talents/brain/jpg/b-right.jpghttp://hiddentalents.org/index.htmhttp://hiddentalents.org/index.htmhttp://members.shaw.ca/hidden-talents/brain/jpg/b-right.jpghttp://members.shaw.ca/hidden-talents/brain/jpg/b-right.jpghttp://members.shaw.ca/hidden-talents/brain/jpg/b-right.jpghttp://members.shaw.ca/hidden-talents/brain/jpg/b-right.jpghttp://members.shaw.ca/hidden-talents/brain/jpg/b-right.jpghttp://members.shaw.ca/hidden-talents/brain/jpg/b-right.jpg


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3D representation of sensory and motor body maps =homonculus

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Primary Somatosensory Cortex

Body Map on SensoryCortex

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Primary Motor Cortex

Topographic map of body on Motorcortex

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CNS: Spinal Cord Spinal cord is enclosed within the

vertebral column from theforamen magnum to L2

Organization of the spinal cordprovides for two-waycommunication to and from thebrain Dorsal roots contain sensory

nerves bring info in Ventral roots contain motor

nerves taking info out tomuscles

Cervical and LumbarEnlargements

Peripheral Nervous System: Spinal nerves (31 pairs)

enter and exit throughintervertebral foramen Somatic (to skeletalmuscles) Autonomic Nervous

System (to glands,organs, blood vessels)


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Peripheral NervousSystem


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Autonomic NervousSystem (ANS)

Automatic Not

Voluntary?EX: Control of heart rate,respiration rate

Article about monks changing body temperature:http://www.nytimes.com/1982/02/09/science/science-watch-heat-from-meditation.html

Movie Relaxation response: http://www.pbs.org/saf/1310/video/watchonline.htm

Benson and Monk Movie in Tibet (starts with Alan Alda in lab) :

http://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=*&squery=%2BClipID%3A5+%2BVideoAsset%3Apbssaf1310&inputField=%20&entire=No&ccstart=2069479&ccend=3318395&videoID=pbssaf1310

D (F h Fl h D
http://www.nytimes.com/1982/02/09/science/science-watch-heat-from-meditation.htmlhttp://www.pbs.org/saf/1310/video/watchonline.htmhttp://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=*&squery=+ClipID:5++VideoAsset:pbssaf1310&inputField=%20&entire=No&ccstart=2069479&ccend=3318395&videoID=pbssaf1310http://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=*&squery=+ClipID:5++VideoAsset:pbssaf1310&inputField=%20&entire=No&ccstart=2069479&ccend=3318395&videoID=pbssaf1310http://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=*&squery=+ClipID:5++VideoAsset:pbssaf1310&inputField=%20&entire=No&ccstart=2069479&ccend=3318395&videoID=pbssaf1310http://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=*&squery=+ClipID:5++VideoAsset:pbssaf1310&inputField=%20&entire=No&ccstart=2069479&ccend=3318395&videoID=pbssaf1310http://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=*&squery=+ClipID:5++VideoAsset:pbssaf1310&inputField=%20&entire=No&ccstart=2069479&ccend=3318395&videoID=pbssaf1310http://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=*&squery=+ClipID:5++VideoAsset:pbssaf1310&inputField=%20&entire=No&ccstart=2069479&ccend=3318395&videoID=pbssaf1310http://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=*&squery=+ClipID:5++VideoAsset:pbssaf1310&inputField=%20&entire=No&ccstart=2069479&ccend=3318395&videoID=pbssaf1310http://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=*&squery=+ClipID:5++VideoAsset:pbssaf1310&inputField=%20&entire=No&ccstart=2069479&ccend=3318395&videoID=pbssaf1310http://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=*&squery=+ClipID:5++VideoAsset:pbssaf1310&inputField=%20&entire=No&ccstart=2069479&ccend=3318395&videoID=pbssaf1310http://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=*&squery=+ClipID:5++VideoAsset:pbssaf1310&inputField=%20&entire=No&ccstart=2069479&ccend=3318395&videoID=pbssaf1310http://www.pbs.org/saf/1310/video/watchonline.htmhttp://www.nytimes.com/1982/02/09/science/science-watch-heat-from-meditation.htmlhttp://www.nytimes.com/1982/02/09/science/science-watch-heat-from-meditation.htmlhttp://www.nytimes.com/1982/02/09/science/science-watch-heat-from-meditation.htmlhttp://www.nytimes.com/1982/02/09/science/science-watch-heat-from-meditation.htmlhttp://www.nytimes.com/1982/02/09/science/science-watch-heat-from-meditation.htmlhttp://www.nytimes.com/1982/02/09/science/science-watch-heat-from-meditation.htmlhttp://www.nytimes.com/1982/02/09/science/science-watch-heat-from-meditation.htmlhttp://www.nytimes.com/1982/02/09/science/science-watch-heat-from-meditation.htmlhttp://www.nytimes.com/1982/02/09/science/science-watch-heat-from-meditation.htmlhttp://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=*&squery=%2BClipID%3A5+%2BVideoAsset%3Apbssaf1310&inputField=%20&entire=No&ccstart=2069479&ccend=3318395&videoID=pbssaf1310


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Organ PNS SNS

Eye ConstrictsPupils

Constrictspupils

Stomach Increase

digestion,motility,elimination

Decrease

digestion,motility,elimination

SalivaryGland

Increasesalivaproduction

Decreasesalivaproduction

Heart Decreaseheart rate

Increaseheart rate

Lungs Constrictairways

Dilateairways

Genitals Erection Ejaculation,orgasm

http://itc.gsw.edu/faculty/gfisk/anim/autonomicns.swf

ANS: Two Divisions (Fight or Flight AND Restand Digest)
http://itc.gsw.edu/faculty/gfisk/anim/autonomicns.swfhttp://itc.gsw.edu/faculty/gfisk/anim/autonomicns.swf


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Cells of Nervous Tissue: Neurons and Glia

FUNCTIONS Neurons excitable cells that transmit electrical

signals, connect with each other to form circuits,

detect, integrate and respond to signals. Majorplayers of nervous system (10% of cells)

Glia supporting cells that fill space aroundneurons and do many other jobs (e.g. maintain ionconcentrations especially [K+ ]in extracellular fluid,serve as a scaffold for neuron migration duringdevelopment, wrap axons and so much more (90% of cells).

Glia

Neurons

N ur n An t m


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Neuron Anatomy

Shape


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Classification of NeuronsShapeLocationFunction: Motor neurons sensory neurons interneurons


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Glia

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Gli A t t


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Glia: Astrocytes arethe most abundant

cells in nervous tissue

Functions: Glue old idea when not much was known Control regional blood flow in the brain at

blood brain barrierhttp://www.sciencenews.org/view/generic/id/3

4048/title/Astrocytes_are_rising_starsANDhttp://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/

Promote neurogenesis of stem cellshttp://www.hhmi.org/news/stevens2.html

Form network that propagates slow

calcium waves throughout the brain(through gap junctions) Wrap neurons and their synaptic endings Act as scaffolds for migration of

developing neurons (e.g. Bergmann) Protect cells during brain ischemia (from

cardiac arrest, stroke, trauma) by soppingup waste (K+, glutamate)

Act as phagocytesScaffold for Neurons (Bergmann glia in cerebellum)

Blood Brain Barrier

go en rocytes an c wann
http://www.sciencenews.org/view/generic/id/34048/title/Astrocytes_are_rising_starshttp://www.sciencenews.org/view/generic/id/34048/title/Astrocytes_are_rising_starshttp://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://www.hhmi.org/news/stevens2.htmlhttp://www.hhmi.org/news/stevens2.htmlhttp://www.hhmi.org/news/stevens2.htmlhttp://www.hhmi.org/news/stevens2.htmlhttp://www.hhmi.org/news/stevens2.htmlhttp://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://power.healingmindn.com/2009/01/20/fmri-neuroscience-advances-in-mind-reading-scans/http://www.sciencenews.org/view/generic/id/34048/title/Astrocytes_are_rising_starshttp://www.sciencenews.org/view/generic/id/34048/title/Astrocytes_are_rising_starshttp://www.sciencenews.org/view/generic/id/34048/title/Astrocytes_are_rising_stars


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go en rocytes an c wanncells are glia that wrap and

insulate axons

Oligodendrodrocytes:

Wrap axons in the CNS

Schwann cells: Make myelin sheath in

the PNS Sheath is the

insulation that makesAP propagation fast (150 m/s vs. 1 m/s)

Sheath acts as abridge forregeneration of axons

Myelinated nerve bundleof axons


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Neurophysiology: Concepts toUnderstand

Resting PotentialExcitation Secretion Coupling (calcium)

Graded Synaptic Potentials

Excitatory Inhibitory

Threshold

Action PotentialsPropagation

Circuits Wiring of cells to each other

matters! 30


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Resting Potential

mV

time

0

-100

+100


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SynapseDEF: An anatomically, chemically and functionally specialized region

between two cells that mediates information transfer.

Cells in the CNS receive as many as 10,000 synapses

**** Information transfer can be excitatory or inhibitoryHow is this different from the neuromuscular junction?

Chemical Synapses A closer look


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Chemical Synapses A closer look

Anatomical/Chemical Specializations of Chemical Synapses include:

Presynaptic terminal filled with synaptic vesicles and Ca channels

Postsynaptic specializations including high density of transmitter receptors

Fluid-filled space called synaptic cleft often filled with special molecules which may includeenzymes to breakdown transmitter, synapse-stabilizer molecules, and other interesting

cells/molecules

l


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Synaptic Potentials:Excitation -

Secretion (calcium)

mV

time

0

-100

+100

http://www.blackwellpublishing.com/matthew

s/neurotrans.html

N t itt
http://www.blackwellpublishing.com/matthews/neurotrans.htmlhttp://www.blackwellpublishing.com/matthews/neurotrans.htmlhttp://www.blackwellpublishing.com/matthews/neurotrans.htmlhttp://www.blackwellpublishing.com/matthews/neurotrans.html


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Neurotransmitters

More than 50 differentneurotransmitters havebeen identified.

NT classified according to1. Functional effects

1. Excitatory2. Inhibitory

2. Chemical structure1. Acetylcholine Alzheimers?2. Amino acids MSG ?3. Neuropeptides Opiates,Oxycontin?4. Biogenic amines Cocaine?

Prozac, Milk?5. Purines Caffeine,

Chocalate?6. Hormones Testosterone?7. Gases Nitrous?

8. Lipids Cannabinoids likemarijuana?

Mouse party: http://learn.genetics.utah.edu/content/addiction/drugs/mouse.html

NT, Drugs INFO: http://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swfhttp://www.nationalfamilies.org/brain/index.html
http://learn.genetics.utah.edu/content/addiction/drugs/mouse.htmlhttp://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swfhttp://www.nationalfamilies.org/brain/index.htmlhttp://www.nationalfamilies.org/brain/index.htmlhttp://www.nationalfamilies.org/brain/index.htmlhttp://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swfhttp://www.nationalfamilies.org/brain/index.htmlhttp://www.nationalfamilies.org/brain/index.htmlhttp://www.nationalfamilies.org/brain/index.htmlhttp://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swfhttp://learn.genetics.utah.edu/content/addiction/drugs/mouse.html


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2 Types of Post-synaptic Potentials (PSPs)EPSP excitatory postsynapticpotentials aregraded potentials

that depolarize cell.

IPSP inhibitory postsynapticpotentials aregraded potentials

hyperpolarize the cell.

I t ti S ti I f ti AP


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Integrating Synaptic Information AP or noAP?

EPSPs and IPSPS add together

EPSP + EPSP can add to reach threshold for AP generation IPSP + EPSP can cancel each other out

Spatial and temporal summation allow


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Spatial and temporal summation allowintegration of neuronal signaling

S IMPACT B h i !!!


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Synapses IMPACT Behavior!!!

Tabuchi et al., 2007. A neuroligin-3 mutation implicated inautism increases inhibitory synaptic transmission in

mice. Science. 318: 71-76. 39


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Digression For Fun (NT and DRUGS)

40

Neurotransmitters


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Neurotransmitters

More than 50 differentneurotransmitters havebeen identified.

NT classified according to1. Functional effects

1. Excitatory2. Inhibitory

2. Chemical structure1. Acetylcholine Alzheimers?2. Amino acids MSG ?3. Neuropeptides Opiates,Oxycontin?4. Biogenic amines Cocaine?

Prozac, Milk?5. Purines Caffeine,

Chocalate?6. Hormones Testosterone?7. Gases Nitrous?

8. Lipids Cannabinoids likemarijuana?

Mouse party: http://learn.genetics.utah.edu/content/addiction/drugs/mouse.html

NT, Drugs INFO: http://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swfhttp://www.nationalfamilies.org/brain/index.html

Reward (Dopamine and Cocaine) and Mood Pathways (Serotonin and
http://learn.genetics.utah.edu/content/addiction/drugs/mouse.htmlhttp://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swfhttp://www.nationalfamilies.org/brain/index.htmlhttp://www.nationalfamilies.org/brain/index.htmlhttp://www.nationalfamilies.org/brain/index.htmlhttp://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swfhttp://www.nationalfamilies.org/brain/index.htmlhttp://www.nationalfamilies.org/brain/index.htmlhttp://www.nationalfamilies.org/brain/index.htmlhttp://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swfhttp://learn.genetics.utah.edu/content/addiction/drugs/mouse.html


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Reward (Dopamine and Cocaine) and Mood Pathways (Serotonin andProzac)Transmitters are released by neurons that make connections with many parts of thebrain and can have wide-reaching effects on lots of information processing.

http://learn.genetics.utah.edu/content/addiction/reward/neurontalk.html

For FUN: A closer look at Amines made
http://learn.genetics.utah.edu/content/addiction/reward/neurontalk.htmlhttp://learn.genetics.utah.edu/content/addiction/reward/neurontalk.html


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For FUN: A closer look at Amines madefrom amino acids

Biogenic Amines: Derived from the amino acid tyrosine.

Actions: Produce rewarding and pleasurable feelings

DopamineTo LOW: Parkinsons disease: Dopamine neurons in a part of the

brain called substantia nigra die.http://www.youtube.com/watch?v=QFtgV1vqwiE

Too HIGH: Schizophrenia, Cocaine and hereNorepinephrine (and epinephrine)

Too HIGH:

Drugs: Amphetamines (act as NE,DA), Tricyclic antidepressants(decrease breakdown), Cocaine (decreases breakdown)Stress: (Fight or flight response) leads to increased heart rate,blood pressure, infertility)

Indoleamines: Derived from the amino acid tryptophan. Feelingdepressed? Amino acid tryptophan is precursor for 5HT and canbe low in diet.Serotonin (5HT)Eat more chocolate, oats, bananas, durians, mangoes,

dried dates, milk,yogurt, cottage cheese, red meat,eggs, fish, poultry,sesame, chickpeas, sunflower seeds, pumpkin seeds, spirulina, and peanuts.To LOW: depressionToo High (Drugs that increase levels): LSD Ecstasy: increases 5HT followed by depletion SSRIs e.g. Prozac: antidepressant increases serotonin by

blocking re-uptake

Melatonin (circadian rhythms and sleep)

F F l l k i id
http://www.youtube.com/watch?v=QFtgV1vqwiEhttp://faculty.washington.edu/chudler/schiz.htmlhttp://www.pbs.org/wnet/closetohome/animation/coca-anim2-main.htmlhttp://www.drugabuse.gov/Infofacts/cocaine.htmlhttp://en.wikipedia.org/wiki/Date_Palmhttp://en.wikipedia.org/wiki/Date_Palmhttp://en.wikipedia.org/wiki/Milkhttp://en.wikipedia.org/wiki/Yogurthttp://en.wikipedia.org/wiki/Cottage_cheesehttp://en.wikipedia.org/wiki/Cottage_cheesehttp://en.wikipedia.org/wiki/Cottage_cheesehttp://en.wikipedia.org/wiki/Cottage_cheesehttp://en.wikipedia.org/wiki/Oathttp://en.wikipedia.org/wiki/Red_meathttp://en.wikipedia.org/wiki/Red_meathttp://en.wikipedia.org/wiki/Egg_(food)http://en.wikipedia.org/wiki/Durianhttp://en.wikipedia.org/wiki/Fishhttp://en.wikipedia.org/wiki/Fishhttp://en.wikipedia.org/wiki/Fishhttp://en.wikipedia.org/wiki/Poultryhttp://en.wikipedia.org/wiki/Poultryhttp://en.wikipedia.org/wiki/Sesamehttp://en.wikipedia.org/wiki/Sesamehttp://en.wikipedia.org/wiki/Date_Palmhttp://en.wikipedia.org/wiki/Chickpeahttp://en.wikipedia.org/wiki/Chickpeahttp://en.wikipedia.org/wiki/Chickpeahttp://en.wikipedia.org/wiki/Chickpeahttp://en.wikipedia.org/wiki/Yogurthttp://en.wikipedia.org/wiki/Sunflower_seedshttp://en.wikipedia.org/wiki/Sunflower_seedshttp://en.wikipedia.org/wiki/Sunflower_seedshttp://en.wikipedia.org/wiki/Cottage_cheesehttp://en.wikipedia.org/wiki/Pumpkin_seedshttp://en.wikipedia.org/wiki/Pumpkin_seedshttp://en.wikipedia.org/wiki/Pumpkin_seedshttp://en.wikipedia.org/wiki/Spirulina_(dietary_supplement)http://en.wikipedia.org/wiki/Spirulina_(dietary_supplement)http://en.wikipedia.org/wiki/Spirulina_(dietary_supplement)http://en.wikipedia.org/wiki/Spirulina_(dietary_supplement)http://en.wikipedia.org/wiki/Fishhttp://en.wikipedia.org/wiki/Poultryhttp://en.wikipedia.org/wiki/Peanuthttp://en.wikipedia.org/wiki/Peanuthttp://en.wikipedia.org/wiki/Sesamehttp://en.wikipedia.org/wiki/Chickpeahttp://en.wikipedia.org/wiki/Sunflower_seedshttp://en.wikipedia.org/wiki/Pumpkin_seedshttp://en.wikipedia.org/wiki/Spirulina_(dietary_supplement)http://en.wikipedia.org/wiki/Peanuthttp://faculty.washington.edu/chudler/lsd.htmlhttp://faculty.washington.edu/chudler/lsd.htmlhttp://en.wikipedia.org/wiki/Peanuthttp://en.wikipedia.org/wiki/Spirulina_(dietary_supplement)http://en.wikipedia.org/wiki/Pumpkin_seedshttp://en.wikipedia.org/wiki/Sunflower_seedshttp://en.wikipedia.org/wiki/Chickpeahttp://en.wikipedia.org/wiki/Sesamehttp://en.wikipedia.org/wiki/Poultryhttp://en.wikipedia.org/wiki/Fishhttp://en.wikipedia.org/wiki/Egg_(food)http://en.wikipedia.org/wiki/Red_meathttp://en.wikipedia.org/wiki/Cottage_cheesehttp://en.wikipedia.org/wiki/Yogurthttp://en.wikipedia.org/wiki/Milkhttp://en.wikipedia.org/wiki/Date_Palmhttp://en.wikipedia.org/wiki/Mangohttp://en.wikipedia.org/wiki/Durianhttp://en.wikipedia.org/wiki/Bananahttp://en.wikipedia.org/wiki/Oathttp://en.wikipedia.org/wiki/Chocolatehttp://www.drugabuse.gov/Infofacts/cocaine.htmlhttp://www.pbs.org/wnet/closetohome/animation/coca-anim2-main.htmlhttp://faculty.washington.edu/chudler/schiz.htmlhttp://www.youtube.com/watch?v=QFtgV1vqwiE


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For Fun: A closer look at Amino Acids

Glutamate- main excitatory transmitter in brain, role in memory andlearning Direct and indirect actions depending on receptor type

Increase (Drug that mimics) monosodium glutamate (MSG) Decrease problems learning?

GABA- main inhibitory transmitter in brain Coupled to K channel in some places

Increase: Drugs that mimic - valium and barbituates act here Disease that decreases (Epilepsy has too little GABA leads to

convulsions)Glycine main inhibitory transmitter in spinal cord

Direct: Cl- channel generates fast IPSP

Disease or drugs that decrease - seizures


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For Fun: More NT

Purines: (ATP, adenosine)Decrease inhibitory actions of adenosine tochange arousal: caffeine, theobromine(chocolate)

Peptides: (e.g. endorphins) blocks pain sensationvia indirect activation of K channels.Natural opiates give runners high.Increase (drugs that mimic actions):morphine, heroin, codeine

http://www.drugabuse.gov/pubs/teaching/default.htmlDissolved gases: (nitric oxide, carbon

monoxide).Increase: Viagra increases NO > caues

vasodilation> penile erection (normallymediated by ANS)

l l
http://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swfhttp://faculty.washington.edu/chudler/caff.htmhttp://faculty.washington.edu/chudler/caff.htmhttp://learn.genetics.utah.edu/content/addiction/drugs/abuse.htmlhttp://www.drugabuse.gov/pubs/teaching/default.htmlhttp://www.drugabuse.gov/pubs/teaching/default.htmlhttp://www.drugabuse.gov/pubs/teaching/default.htmlhttp://www.drugabuse.gov/pubs/teaching/default.htmlhttp://www.drugabuse.gov/pubs/teaching/default.htmlhttp://learn.genetics.utah.edu/content/addiction/drugs/abuse.htmlhttp://faculty.washington.edu/chudler/caff.htmhttp://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swf


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Serotonin levels Designer Drugs tochange moods?

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Neurotransmitters: Disease/HealthDeep Brain Stim for Parkinsons: http://www.youtube.com/watch?v=QFtgV1vqwiE

Plus/minus cocaine cellular model:http://www.thirteen.org/closetohome/animation/coca-anim-main.html and moreinfo: http://www.drugabuse.gov/Infofacts/cocaine.html

Recreational Drugs (Mouse Party): http://learn.genetics.utah.edu/content/addiction/drugs/

http://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swf

Epilepsy is a neurological disorder characterized by unprovoked, recurring seizuresthat disrupt the nervous system and can cause mental and physical dysfunction.In the U.S., about 2.5 million people are affected by epilepsy and seizures. About10% of the American population will experience at least one seizure during theirlifetime.Drugs that help relieve symptoms either increase inhibition or decreaseexcitation:

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Summary Chemical Synaptic Transmission
http://www.youtube.com/watch?v=QFtgV1vqwiEhttp://www.thirteen.org/closetohome/animation/coca-anim-main.htmlhttp://www.drugabuse.gov/Infofacts/cocaine.htmlhttp://learn.genetics.utah.edu/content/addiction/drugs/http://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swfhttp://www.psych.ualberta.ca/~ITL/flash/stimulants_draft.swfhttp://learn.genetics.utah.edu/content/addiction/drugs/http://www.drugabuse.gov/Infofacts/cocaine.htmlhttp://www.thirteen.org/closetohome/animation/coca-anim-main.htmlhttp://www.thirteen.org/closetohome/animation/coca-anim-main.htmlhttp://www.thirteen.org/closetohome/animation/coca-anim-main.htmlhttp://www.thirteen.org/closetohome/animation/coca-anim-main.htmlhttp://www.thirteen.org/closetohome/animation/coca-anim-main.htmlhttp://www.youtube.com/watch?v=QFtgV1vqwiE


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y y pSequence of events Action Potential reaches the axonal terminal of the presynaptic neuron Depolarization opens voltage-gated Ca2+ channels in the presynaptic cell Calcium moves down its electrochemical gradient into the cell where it serves to

depolarize the cell and more importantly act as a signaling molecule. Calcium triggers vesicle fusion with the cell membrane and release ofneurotransmitter into the synaptic cleft

Neurotransmitter diffuses in the cleft. This is the rate limiting step in signaltransmission (.3 5 ms)

Neurotransmitter binds to receptors on the post-synaptic cell to effect a response Often (but not always) the response to transmitter binding is opening of an ion

channel via either direct or indirect transmission (more soon). If the channel provides a path for positive ions to move into the cell (down

electrochemical gradients) the transmitter is excitatory, depolarizes the cell toproduce an EPSP excitatory post-synaptic potential.

If the transmitter provides a path for positive ions to leave the cell or negativeions to enter the cell, resulting in a net hyperpolarization or IPSP (inhibitorypost-synaptic potential), the transmitter is inhibitory.

The response ends when transmitter unbinds from the receptor as a result of fallingconcentrations of the transmitter in the cleft Transmitter degraded by enzymes (like acetylchloinesterase at the NMJ) Transmitter is taken up by re-uptake proteins into the presynaptic neuron,

astrocytes Transmitter diffuses away from cleft

http://www.blackwellpublishing.com/matthews/neurotrans.html

Integrating Synaptic Information AP or no
http://www.blackwellpublishing.com/matthews/neurotrans.htmlhttp://www.blackwellpublishing.com/matthews/neurotrans.htmlhttp://www.blackwellpublishing.com/matthews/neurotrans.html


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Integrating Synaptic Information AP or noAP?

EPSPs and IPSPS add together

EPSP + EPSP can add to reach threshold for AP generation IPSP + EPSP can cancel each other out


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Draw an Action Potential


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Draw an Action PotentialLabel: EPSP, Threshold, Depolarization, Overshoot, Repolarization,

resting potentialHow long are action potentials?

52

mV

time

0

-100

+100

Check your


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Check yourDrawing

Actions Potentials are used to send messages


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Actions Potentials are used to send messagesquickly (2 300 miles/hour)

Different Axons Conduct APs at Different Speeds


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p

Factors that determine speed: Diameter of the axon (the larger the diameter, the faster the AP

travels)

Insulated or NOT (Myelination/Unmyelinated): myelinationdramatically increases impulse speed.Classification of Axons:

Biggest myelinated conduct APs the fastest: 300 mph (150meters/second) EX: MOTOR AXONS (Ia)

Smallest, unmyelinated fibers conduct APs the slowest:2 mph (1

meter/second) EX: PAIN FIBERS (C fibers)

Slow AP Propagation: Continuous


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Slow AP Propagation: Continuous

Properties:An new action potentialoccurs in each little patch

of membraneSpeed: 1 meter/second

Faster AP Propagation: Saltatory


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Faster AP Propagation: SaltatorySpeed = 15 - 120 meters/second

Multiple Sclerosis (MS) effects AP


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Multiple Sclerosis (MS) effects APpropagation:

MS is an autoimmune disease

Glial cells that form myelin in the CNS and PNS are attacked by theimmune system and killed

AP propagation is disrupted > many APs fail to reach axon terminaltherefore communication is disrupted

Symptoms: Vision and hearing problems, muscle weakness, and urinary

incontinence Treatments: Drugs that block immune system (like interferon beta-1a and -1b,

Avonex, Betaseran, and Copazone)

Web Info: Multiple Sclerosis: http://www.youtube.com/watch?v=qgySDmRRzxY

Montel Williams on Oprah:

http://www.youtube.com/watch?v=rgS4H-hTo0Q&feature=related NYT Patient Stories: http://www.nytimes.com/interactive/2008/12/03/health/healthguide/TE_MULTIPLESCLEROSIS.html

http://www.nationalmssociety.org/about-multiple-sclerosis/index.aspx

Interpreting Action PotentialsK C t AP F d Sti l
http://www.youtube.com/watch?v=qgySDmRRzxYhttp://www.youtube.com/watch?v=rgS4H-hTo0Q&feature=relatedhttp://www.nytimes.com/interactive/2008/12/03/health/healthguide/TE_MULTIPLESCLEROSIS.htmlhttp://www.nationalmssociety.org/about-multiple-sclerosis/index.aspxhttp://www.nationalmssociety.org/about-multiple-sclerosis/index.aspxhttp://www.nationalmssociety.org/about-multiple-sclerosis/index.aspxhttp://www.nationalmssociety.org/about-multiple-sclerosis/index.aspxhttp://www.nationalmssociety.org/about-multiple-sclerosis/index.aspxhttp://www.nationalmssociety.org/about-multiple-sclerosis/index.aspxhttp://www.nationalmssociety.org/about-multiple-sclerosis/index.aspxhttp://www.nytimes.com/interactive/2008/12/03/health/healthguide/TE_MULTIPLESCLEROSIS.htmlhttp://www.youtube.com/watch?v=rgS4H-hTo0Q&feature=relatedhttp://www.youtube.com/watch?v=rgS4H-hTo0Q&feature=relatedhttp://www.youtube.com/watch?v=rgS4H-hTo0Q&feature=relatedhttp://www.youtube.com/watch?v=qgySDmRRzxY


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p gKey Concept: AP Frequency codes Stimulus

Intensity (Loud sound vs. soft sound, bright light vs. dim light)

Interpreting APsP h h f P d l f


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p gKey Concept: Pathway that fires APs determines quality of

information. Is the signal from the environment a green light, agentle touch to your arm or to your face, a painful pinch, or a

soothing sound?


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Interpreting APSKey Concept: Pathways carrying information can diverge and

converge, taking info to different parts of the brain for processing

e.g. smells trigger memories and emotions (e.g. scent of a rosereminds you of your mother)

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Generating Behaviors: Reflex Arc Simple


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Circuit

There are five components of a reflex arc Receptor site of stimulus Sensory neuron transmits the afferent impulse to the CNS Integration center within the CNS Motor neuron conducts efferent APS from the integration

center to an effector Effector muscle fiber or gland that responds to the APs


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Review the details of the reflex here:h // h d / b / / 1/ 6 1 h l
http://www.uth.tmc.edu/nba/neuroscience/s1/i6-1.htmlhttp://www.uth.tmc.edu/nba/neuroscience/s1/i6-1.htmlhttp://www.uth.tmc.edu/nba/neuroscience/s1/i6-1.htmlhttp://www.uth.tmc.edu/nba/neuroscience/s1/i6-1.htmlhttp://www.uth.tmc.edu/nba/neuroscience/s1/i6-1.html

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