Cellular Physiology of the Nervous System

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Cellular Physiology of the Nervous System
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Love and the Nervous System

• What brings people together to fall in love?
• Chemistry

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Love and the Nervous System

• What does it feel like when you are in love?
• Electricity

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How Do Nerve Cells Talk to Each Other About Love?

• Chemistry
• Electricity

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The Chemistry and Electricity of the Nervous
System

• L-Glutamate

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Action Potentials 2

• 1.http//en.wikipedia.org/wiki/ImageL-glutamic-ac
  id-skeletal.pngfile

2.http//en.wikipedia.org/wiki/Action_potential
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Topics for Today

• Overview of Function of the Nervous System
• Anatomy of a Neuron

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Topics for Today

• Neurophysiology
• Resting Membrane Potential
• Action Potential
• Synaptic Potential
• Generator Potential

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Topics for Today

• Clinical Correlations

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Topics for Today

• Perception
• Recognizing Faces
• Vision
• Recognizing Ones Self

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Function of the Nervous System

• Helps Maintain Homeostasis
• Responds to internal environment
• Responds to external environment
• Survival of the Organism

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Responding to External Environment

• Volunteer

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Responding to the internal environment

• Volunteer

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Anatomy of the Neuron

• Dendrites
• Receive Information
• Cell Body
• Contains Nucleus and Genetic Information
• Axon
• Transmits information

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Anatomy of the Neuron

• Myelin
• Speeds conduction of action potentials (Nerve
  Impulses)
• Presynaptic Terminal
• Contains synaptic vesicles (with NTX)

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Anatomy of the Neuron

• Synapse
• Site of communication between neurons
• Site of neurotransmitter (NTX) release
• Presynaptic Terminal
• Contains synaptic vesicles (with NTX)

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Anatomy of the Neuron

• Postsynaptic Neuron
• Contains receptors for NTX

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Anatomyof the Neuron
Slide From Brain FactsSociety for Neuroscience
Dendrites
Axon
Cell Body
Myelin
Synapse
Postsynaptic Neuron
Presynaptic Terminals
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Anatomyof the Neuron
Action Potential
Axon
Synaptic Vesicle
Synapse
Presynaptic Terminal
Postsynaptic Neuron
Neurotransmitter
Receptors
Slide From Brain FactsSociety for Neuroscience
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Neurophysiology

• Overview
• From stimulus to movement
• Generator Potential --gt Action Potential
  --gt Synaptic Potential --gt Action Potential
  --gt Synaptic Potential (Endplate
  Potential) --gt Action Potential --gt
  Muscle Contraction

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Resting Membrane Potential

• Neuronal communication occurs as a result of a
  change in the resting membrane potential.

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Resting Membrane Potential

• All cells have them

• Neuron is like a battery

• Unequal distribution of
• charges

• More Na outside,
• More K inside

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Action Potential

• Carries information down axon
• Electrical Impulse
• Na enters via channels
• The RMP depolarizes
• Travels down the axon

Action Potential
RMP
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Action Potential

• Na enters via channels
• The RMP depolarizes
• Becomes inside

-- - - - -
Na
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Action Potential
AP travels at a fixed rate down the axon.
AP
AP
AP travels faster in myelinated axons. ALS and
Multiple Sclerosis are diseases of myelin.
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How Does Information Cross the Synapse?

• Synaptic Transmission
• 1. AP invades presynaptic terminal
• 2. Causes channels for Ca to open
• 3. Ca goes into termnial
• 4. Ca causes NTX to be released
• 5. NTX crosses cleft and binds to RX

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How Does the Information Cross the Synapse?

• How Does the Information Cross the Synapse.

Synaptic Transmission
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Synaptic Potential

• Binding of NTX to receptor causes an electrical
  potential in the neuron.
• 2. If the synaptic potential is large enough, it
  will trigger an action potential

Action Potential
Synaptic Potential
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Generator Potential

• How does information get from tip of finger to
  muscles in the hand?

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Generator Potential

• Stimulus to finger causes electrical signal in
  the sensory neuron
• Signal called a generator potential
• If the generator potential is large enough, it
  triggers an action potential

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Generator Potential
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Clinical Correlations

• Multiple Sclerosis
• Depression
• Local Anesthetics

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Perception

• Recognizing Faces
• Prosopagnosia
• Visual Illusions
• Colors
• Recognizing Ones Self
• Amorphosynthesis Neglect Syndrome

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Topics Covered Today

• Function of the Nervous System
• Anatomy of a Neuron
• Neurophysiology
• Clinical Correlations
• Perception