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239 Cards in this Set
- Front
- Back
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What is an Electrochemical Gradient? What are its components? How is established?
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-Chemical Gradient - Ion Concentrations are Unequal across Membrane
-Creates a Driving Force - Electric Force |
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In Which Direction does K+ want to go?
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Out of the Cell
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In Which Direction does Ca2+ want to go?
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Into the Cell
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In Which Direction does Na+ want to go?
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Into the Cell
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In Which Direction does Cl- want to go?
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Into the Cell
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What is the Nernst Potential? What does it mean?
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-It is the Potential at which the effects of the Chemical Gradient are Balanced by the Electrical Gradient
-Flux due to Diffusion is Equal and Opposite to the Flux due to Electrophoresis |
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What are some other names for Nernst Potential?
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-Equilibrium Potential
-Reversal Potential |
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What is the Equilibrium Potential of Na+?
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+60 mV
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What is the Equilibrium Potential of K+?
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-94 mV
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What is the Equilibrium Potential of Ca2+?
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+136 mV
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What is the Equilibrium Potential of Cl-?
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-86 mV
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The Equilibrium Potential of Na+ is +60 mV. If a Cell is at -20mV, what will Na+ want to do? Why?
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-The Ion will always want to get to Equilibrium
-This means it wants to get the Electrical Gradient to +60 mV -To do this, Na+ must come into the Cell |
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What determines the Overall Resting Potential of a Cell?
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The effect from each Ion in the System
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How can a Neuron's Resting Membrane Potential be calculated? What factors must be considered in this equation?
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-Permeability of the Ion
-Concentration of the Ion Inside the Cell -Concentration of the Ion Outside the Cell |
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How do Excitatory Signals act on the Cell Membrane?
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-Depolarize the Membrane
-Increase the Likelihood of an AP by Increasing the Likelihood of Reaching Threshold |
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How do Inhibitory Signals act on the Cell Membrane?
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-Hyperpolarize the Membrane
-Decrease the Likelihood of an AP by Decreasing the Likelihood of Reaching Threshold |
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What type of Signal makes it MORE likely that a cell will produce an AP?
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Excitatory Signals
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What type of Signal makes it LESS likely that a cell will produce an AP?
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Inhibitory Signals
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What is a Graded Potential? Does this mean an AP will be initiated?
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-A Potential Sent by a Cell that is graded, or preset at a certain value
-Not necessarily. Graded potential can be subthreshold or suprathreshold |
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Compare Graded Potential with APs.
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Graded Potentials:
-Vary in Strength -Lose Strength over Distance -Are Slower than APs |
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What type of Potentials can Decay?
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Graded Potentials
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What type of Potentials do not Decay?
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APs
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How is a Larger or Longer Stimulus coded?
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-Larger or Longer Graded Potential
-Increased AP Frequency |
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What does a Larger or Longer Graded Potential code for?
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Larger or Longer Stimulus
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What does an Increased AP Frequency Code for?
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Larger or Longer Stimulus
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What is an EPSP?
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Excitatory Post-Synaptic Potential
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What is an IPSP?
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Inhibitory Post-Synaptic Potential
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What is Temporal Summation?
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-When Potentials Sum up in Time
-Time Constant is Long Enough for a Cell to Send multiple Graded Potentials that sum up |
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What is Spatial Summation?
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-When Potentials Sum up in Space
-Usually from Multiple Neurons -Hit at the Same place/time and sum up |
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If w Neuron has a Long Time Constant, and sends out multiple graded potentials, what type of summation would we expect to see?
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Temporal
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What type of Time Constant Facilitates Temporal Summation? Why?
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-Long Time Constant
-Gives the Graded Potentials a Longer Time before they Decay -This allows Potentials to Sum up |
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What is the Time Constant? What does it Measure?
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-Describes how long it will take for the Membrane Capacitor to Charge or Discharge
-Essentially tells us How Long the Membrane can "Hang On" to the Signal |
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Describe Spatial Summation.
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-Passively Conducted Signals Originating from Different Sources Add Together
-Inputs from Further Away are Smaller at the Axon Hillock -Length Constant Determines How Big they Will be When they Arrive |
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What type of Length Constant Facilitates Spatial Summation? Why?
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-Large Length Constant
-Allows Potential to be able to travel a longer distance and sum at the Axon Hillock |
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What does it mean if a Neuron has a Longer Time Constant?
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Travels Slower
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What does it mean if a Neuron has a Larger Length Constant?
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Travels Further
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If Neuron A's Potentials Travel Faster than Neuron B's, what can we say about their respective Time Constants?
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Time Constant (rA) for A < Time Constant (rB) for B
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If Neuron A's Potentials Travel Shorter than Neuron B's, what can we say about their respective Length Constants?
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Length Constant (RmA) for A < Length Constant (RmB) for B
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How Does Myelination Affect Length Constant?
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-Increases Resistance by decreasing the Number of Channels
-Current Travels Further -Increases Length Constant |
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How Does Myelination Affect Time Constant?
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-Decreases Membrane Capacitance
-Wave Moves Faster -Decreases Time Constant |
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What is the Overall Effect of Myelination?
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-Increases Length Constant
-Decreases Time Constant |
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What does if mean if Conduction along an Axon is done Orthodromatically?
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It is Moving Towards Distal Terminal
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What does if mean if Conduction along an Axon is done Antidromatically?
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It is Moving Towards the Cell Body
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Why do APs occur?
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-Sodium and Potassium Fluxes
-Changes the Charge on the Cell Membrane -Ion Concentrations are not Changed |
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What are the Major Steps in Neurotransmission?
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-Synthesis
-Storage -Release -Binding (Reception) -Removal/Inactivation |
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What are some different ways that Removal/Inactivation of an NT can occur?
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-Reuptake into the Neuron
-Uptake into Glia -Uptake into the Post-Synaptic Membrane -Degradation/Catabolism -Diffusion |
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What Enzyme is Responsible for the Degration of Catecholamines Intraneuronally?
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MAO - Monamine Oxidase
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What Enzyme is Responsible for the Degration of Catecholamines Intraneuronally?
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COMT - Catechol-O-Methyltransferase
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What does MAO do? Where?
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-Degrade Catecholamines
-Inside the Cell |
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What does COMT do? Where?
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-Degrade Catecholamines
-Outside the Cell |
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What are Ionotropic Receptors? How do they Work? What type of Conduction do they provide?
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-Ligand-Gated
-Direct Gating if Ion Channels -Fast |
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What are Metabotropic Receptors? How do they Work? What type of Conduction do they provide?
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-G-Protein Linked Receptors
-Indirect Gating -Slower |
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What type of Receptors are Ligand Gated?
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Ionotropic Receptors
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What type of Receptors are G-Protein Linked?
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Metabotropic Receptors
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What type of Receptors are fast?
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Ionotropic Receptors
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What type of Receptors are slower?
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Metabotropic Receptors
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Which half of the Spinal Cord contains Sensory Roots?
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Dorsal Half
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Which half of the Spinal Cord contains Motor Roots?
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Ventral Half
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What type of Roots are found in the Ventral Half of the SC?
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Motor
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What type of Roots are found in the Dorsal Half of the SC?
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Sensory
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Adjacent sensory roots innervate overlapping dermatomes so that loss of one spinal nerve does not completely eliminate sensation from that body segment
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Adjacent sensory roots innervate overlapping dermatomes so that loss of one spinal nerve does not completely eliminate sensation from that body segment
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Loss of ONLY T2 spinal root might go undetected
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Loss of ONLY T2 spinal root might go undetected
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What is a Dermatome?
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Area of Skin innervated by One Spinal Nerve
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What Disease often shows up within 1 Single Dermatome?
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Herpes Zoster
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Where are the Cell Bodies of Sensory Axons?
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Dorsal Root Ganglion
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What is found in the Dorsal Root Ganglion?
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Cell Bodies of Sensory Axons
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What is meant by Adequate Stimulus? Give an example.
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-The type of Stimulus needed to get a Receptor to open channels and conduct a signal
-Mechanoreceptors may require Mechanical Deformation to open Channels |
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If a Stimulus can affect a Receptor it is said to be in that Receptor's _____________.
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Receptive Field
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What is Receptive Field?
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The Stimuli or Neurons that can act on a given Receptor
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What type of Neurons have a Larger Receptive Field? Why?
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-Ones that are "Higher" Up
-More Neurons Converge on them |
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What codes for the Nature of a Stimulus?
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Adequate Stimulus
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What codes for the Location of a Stimulus?
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Receptive Field
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What is a Receptor Potential?
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The Potential Generated once a stimulus is Transduced into an internal Graded Potential
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How is the Intensity and Duration of a Stimuli Coded?
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Receptor Potential
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What is a Rapidly Adapting Receptor? What are these good for Coding?
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-Stop Firing Quickly after the Initial Burst
-Detect Change in Stimuli: v and a |
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What is a Slowly Adapting Receptor? What are these good for Coding?
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-Generate APs as long as there is a Stimulus
-Transduce Long-Lasting Stimuli into Long-Term Potentials -Continue firing APs -Maintained Stimuli-Pressure, Touch, Temp |
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What are the 4 Major Characteristics of a Stimulus?
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-Modality - How
-Intensity - Strength -Duration - Time -Location - Where |
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What are Encapsulated Receptors?
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-Layered or Thin
-Capsule serves as a Mechnical Filter -Rapidly Adapting |
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What types of Receptors are better for Rapidly Adapting Receptors, Encapsulated or Non-Encapsulated? Why?
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-Encapsulated
-Capsule Serves as a Mechanical Filter |
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What are Non-Encapsulated Receptors?
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-Free Nerve Endings or Endings with Accessory Structures
-Branched Terminations of the Sensory Fiber |
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What types of Receptors are better for Slowly Adapting Receptors, Encapsulated or Non-Encapsulated? Why?
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-Non-Encapsulated
-Capsule Serves as a Mechanical Filter so it would filter this shit out |
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What is 2 Point Discrimination? What is Dependent on?
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-Minimum Distance at which 2 Stimuli can be discerned
-Receptor Density |
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What type of Receptors (Slowly or Rapidly Adapting) are Muscle Spindles?
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Slowly Adapting
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What type of Receptors (Slowly or Rapidly Adapting) are Hair Follicles?
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Rapidly Adapting
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What types of Somatosensory Perceptions does the DCML code for? What is this termed?
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-Discrimitive Touch
-Vibration -Proprioception -Epicritc |
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What types of Somatosensory Perceptions does the STT code for? What is this termed?
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-Crude Touch
-Pain -Temperature -Protopathic |
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Which system codes for the following?
-Discrimitive Touch -Vibration -Proprioception |
DCML
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Which system codes for the following?
-Crude Touch -Pain -Temperature |
STT
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Which system codes for Epicritic Stuff?
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DCML
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Which system codes for Protopathic Stuff?
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STT
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What type of Sensory Fibers are found in the DCML? Why?
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-AAlpha, ABeta, and ADelta - Larger and Myelinated
-Low Threshold Fibers -Needed for Epicritic Shit |
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What type of Sensory Fibers are found in the STT? Why?
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-ADelta, C - Smaller (ADelta - Myelinated, C - Unmyelinated)
-Don't need Low Threshold |
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In which Tract do we find Larger Myelinated AAlpha, ABeta, and ADelta Fibers?
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DCML
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In which Tract do we find Smaller ADelta and C Fibers?
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STT
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Where is the Relay Nuclei for the Body Somatosensory Input found?
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VPL - Ventral Posterior Lateral Thalamus
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Where is the Relay Nuclei for the Head Somatosensory Input found?
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VPM - Ventral Posterior Medial Thalamus
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The VPL is the Relay Nuclei for what type if Somatosensory Input?
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Body
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The VPM is the Relay Nuclei for what type if Somatosensory Input?
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Head
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Describe the Path of DCML Fibers.
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-1st Oder Neuron - Cell Body is the DRG, Axon Ascends in the Fasciculus Gracilis (Legs and Trunk) or Cuneatus (Arms) of the Dorsal Column
-2nd Order Neuron - Cell Body is in the Nucleus Gracilis or Cuneatus in the Caudal Medulla, Axons Cross at this Level at the Internal Arcuate, Ascend in the Medial Lemniscus -3rd Order Neuron - In the VPL or VPM of the Contralateral Thalamus, Project to SS Cortex in Postcentral Gyrus |
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Where do Axons Ascend in the DCML System? Which side compared to the stimulus? Which Neuron (Order) is this?
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-Fasciculus Gracilis (Legs and Trunk) or Cuneatus (Arms) of the Dorsal Column
-Ipsalateral Side -1st Order |
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Where is the 2nd Order Neuron of the DCML System found? Which side compared to the stimulus?
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-Nucleus Gracilis or Cuneatus of the Caudal Medulla
-Ipsaleteral |
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Where do Axons of the DCML System Cross? Which Neuron (Order) is this?
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-Internal Arcuate at the Caudal Medulla
-Axons of the 2nd Order Neuron from Nucleus Gracilis or Cuneatus of the Caudal Medulla |
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Where do Axons of 2nd Order Neurons Ascend in the DCML System? Which side compared to the stimulus? Where do they Project to?
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-Medial Lemniscus
-Contralateral -VPL or VPM of the Thalamus |
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Where are 3rd Order Neurons of the DCML System Found? Which side compared to the stimulus? Where do they Project to?
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-VPL or VPM of the Thalamus
-Contralateral -SS Cortex |
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Where are the Fasciclus Gracilis and Fasciculus Cuneatus Found?
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-Dorsal Column
-Posterior Funiculus |
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What Happens in Multiple Sclerosis in the Posterior Column?
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-Demyelination of the Posterior Columns (Roots and Columns are Damaged) in the CNS
-Impaired Tactile Sense -Loss of Proprioception -Multiple Lesions in Space and Throughout Time |
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What Happens in Syphilis in the Posterior Column?
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-Slow, Progressive Degeneration of the SC
-Occurs in the Tertiary Phase of Syphilis -Impaired Vibration Sense -Decreased Tactile Sensation -Loss of Proprioception |
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In MS, is White Matter or Gray Matter Affected? Why?
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-White Matter
-Demyelinating |
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What is Guillan-Barre Syndrome? What does it affect?
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-Demyelinating and Inflammatory Disordering
-Schwann Cells - PNS |
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Demyelination in the PNS is called what? In the CNS?
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-Guillan-Barre Syndrome
-MS |
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Describe the Path of STT Fibers.
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-1st Order Neuron - Cell Body is the DRG. Goes up or Down for 1-2 Spinal Levels and Forms the Posterolateral Tract of Lissauer.
-2nd Order Neuron - Cell Body is in Ipsalateral Dorsal Horn, Axons Cross at Anterior White Commissure, Ascend in Contralateral STT, IN the Upper Medulla and Pons Ascend in the Spinal Lemniscus -3rd Order Neuron - Found in the VPL of the Contralateral Thalamus and Project to Opposite SS Cortex |
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STT
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Arms - Medial
Legs - Latera |
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DCML
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Arms - Lateral
Legs - Medial |
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Where do Axons Ascend in the STT System? Which side compared to the stimulus? Which Neuron (Order) is this?
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-STT, Spinal Lemniscus in the Upper Medulla and Pons
-Contralateral -2nd Order |
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Where is the 2nd Order Neuron of the DCML System found? Which side compared to the stimulus?
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-Dorsal Horn
-Ipsalateral Side |
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Where do Axons of the STT System Cross? Which Neuron (Order) is this?
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-Anterior White Commissure of the SC
-2nd |
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Where do Axons of 2nd Order Neurons Ascend in the STT System? Which side compared to the stimulus? Where do they Project to?
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-STT, Spinal Lemniscus in the Upper Medulla and Pons
-Cell Body is Ipsalteral, Axons Ascend Contralateral -VPL of the Thalamus |
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Where are 3rd Order Neurons of the STT System Found? Which side compared to the stimulus? Where do they Project to?
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-VPL of the Thalamus
-Contralateral -SS Cortex |
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Where is the 1st Order Neuron of the STT System Found? Describe its Path to the 2nd Order Neuron?
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-DRG
-Goes Up or Down for 1-2 Spinal Levels and Forms the Posterolateral Tract of Lissauer. Synapses on 2nd Order Neuron on Ipsalateral Dorsal Horn |
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If we have a Left Side Lesion at the Level of the Thoracic Spinal Cord, Which Sensory Tract to the Right Foot will be Affected?? Why?
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-STT
-DCML is Ascending on the Ipsalateral (Right) Side and will cross at the Caudal Medulla -STT is Ascending on the Contralateral (Left) Side and will be cut |
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If we have a Left Side Lesion at the Level of the Brainstem, Which Sensory Tract to the Right Foot will be Affected?? Why?
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-Both
-At the Level of the Brainstem, Both Tracts have Crossed, DCML at the Caudal Medulla and STT at the Anterior White Commissure, so this lesion will affect both |
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What is the Main Motor Efferent Pathway?
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Corticospinal Tract
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How many Neurons are in a Typical Motor Tract? What are they?
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-2
-UMN and LMN |
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What is another Name for Direct Motor Pathways?
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Pyramidal Tracts
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What is another Name for Pyramidal Tracts?
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Direct Motor Pathway
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Where types of Motor Neurons are the Pyramidal Cells of the Motor Cortex?
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UMNs
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Where are Lower Motor Neurons Cell Bodies Found?
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Ventral Horn at the Level of Innervation
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Where are UMN Cell Bodies Found?
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-Precentral Gyrus
-Premotor Area |
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Describe the Pathway of CST.
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-UMN - Originate in the Motor Cortex, Output is Carried by Pyramidal Cells, Axons Descend in Peduncles, Axons Cross (90%) at Caudal Medulla, Descend in the Lateral CST in the Lateral Funiculus or the Anterior CST in the Anterior Funiculus (If they don't Cross)
-LMN - At the Level of Innervation in the Ventral Horn. Innervate Muscle |
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Where do CST Axons Cross? What Percentage? Where does descend?
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-Caudal Medulla
-90% -Lateral CST in the Lateral Funiculus |
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Where do CST Axons Cross? What Percentage? Where do the ones that don't cross descend?
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-Caudal Medulla
-10% -Anterior CST in the Anterior (Ventral) Funiculus |
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Trace the Pathway of Motor Output.
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-UMN - Corona Radiata, Internal Capsule, Midbrain, Pons, Medulla, LCST
-LMN - Ventral Horn, to the Muscle |
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Where are the Medullary Pyramids Found?
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Anterior Medulla
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What Structure is Found on the Anterior Medulla? What does this shit do?
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-Medullary Pyramids
-Motor Tracts |
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Where in the SC does the STT Ascend?
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Anterolateral Portion
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Which Tracts are Found in the Posterior Funiculus?
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Sensory - DCML
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Which Tracts are Found in the Anterior Funiculus?
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Motor Tracts
-Anterior CST - CST Fibers that Didn't Cross -Reticulospinal -Vestibulospinal |
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Which Tracts are Found in the Lateral Funiculus?
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-Sensory - STT and Anterolateral System
-Motor - Lateral CST |
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What are the Laminae in the Gray Matter of the SC? Where does Numbering Start?
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-Sections Based on what type of Neurons are found
-Dorsal Side |
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Where are Alpha and Gamma Motor Neuron Cells Bodies that Innervate Skeletal Muscle?
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Lamina 9
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What type of Neuron Cell Bodies are Found in Lamina 9 of the Gray Matter of the SC?
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Alpha and Gamma Motor Neurons that Innervate Skeletal Muscle
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At which Levels of the SC is the Cervical Enlargement Found?
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C5-T1
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At which Levels of the SC is the Lumbar Enlargement Found?
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L2-S3
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What is another name for the Extrapyramidal System?
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Indirect System
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What is another name for the Indirect System?
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Extrapyramidal System
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What is the Extrapyramidal System?
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-Not part of the Pyramidal System
-Involved in Regulating: Axial Muscles that Maintain Balance, Coarse Limb Movements, Head, Neck, and Eye Movements -Includes Rubrospinal, Vetibulospinal, Reticulospinal, and Tectospinal Tracts -Heavily Dependent on Reflex Activity |
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What type of movements is the Extrapyramidal System involved in regulating?
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-Axial Muscles that Maintain Balance
-Coarse Limb Movements -Head, Neck, and Eye Movements |
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Which Tracts are Part of the Indirect System? What Type of Activity is this System heavily dependent on?
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-Rubrospinal, Vetibulospinal, Reticulospinal, and Tectospinal Tracts
-Heavily Dependent on Reflex Activity |
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Which Motor Control System is Heavily Dependent on Reflex Activity?
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Indirect (Extrapyramidal) System
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What Function Does the Reticulospinal Tract serve?
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Maintains Posture and Balance (Feedforward)
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What Function Does the Vestibulospinal Tract serve?
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Maintains Posture and Balance (Feedback)
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What Function Does the Tectospinal Tract serve?
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Mediates Head Movements
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What Function Does the Rubrospinal Tract serve?
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Controls Flexor Muscles
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Which Indirect Systems help regulate Posture and Balance? Which one is Feedforward? Feedback?
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Reticulospinal (Feedforward) and Vestibulospinal (Feedback) Tracts
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Which Indirect Systems help mediate Head Movements?
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Tectospinal Tract
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Which Indirect Systems help Control Flexor Muscles?
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Rubrospinal Tract
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Which Indirect Tract is responsible for Feedforward Adjustments in Posture and Balance?
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Reticulospinal Tract
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Which Indirect Tract is responsible for Feedback Adjustments in Posture and Balance?
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Vestibulospinal Tract
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What type of Movements is the Tectospinal Tract Responsible for?
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-Reflexive Head Turning to Orient Stimuli (Especially Visual and Auditory)
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Which Indirect Motor System Tract are the Colliculi part of? What does this system do? What does the Superior Colliculus contain? Inferior Colliculus
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-Tectospinal
-Reflexive Head Turning to Orient Stimuli -Superior Colliculus - A Visual Reflex Center -Inferior Colliculus - An Auditory Reflex Center |
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Where are Cell Bodies of the Rubrospinal Tract Found? What is this Tract Responsible for?
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-Red Nucleus
-Control of Flexors |
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What is the Decorticate Position? Decerebrate?
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-Decorticate - Arms Flexed, Legs Extended
-Decerebrate - Arms and Legs Extended |
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What is the Decorticate Position? Decerebrate? What causes each?
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-Decorticate - Arms Flexed, Legs Extended - Bilateral Thalamus or Cerebral Cortex Damage
-Decerebrate - Arms and Legs Extended - Take Midbrain Offline (Just Below or at Red Nucleus) |
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If there is Damage at the Red Nucleus in a Coma Patient, what position will they be see them in?
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Decerebrate
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If there is Bilateral Thalamus or CC Damage in a Coma Patient, what position will they be see them in?
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Decorticate
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If a Coma patient is in the Decerebrate Position, what is likely the deal with their tracts?
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-Damage at or below the Red Nucleus
-Loss of Rubrospinal Tract Influence |
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If a Coma patient is in the Decorticate Position, what is likely the deal with their tracts?
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-Brainstem Motor Centers are Working
-No Modulation from CST |
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What are the Major Types of Axons associated with Skeletal Muscle?
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-Alpha Motor Neurons
-Muscle Spindle Afferents (Ia, IIa) -Muscle Spindle Efferents - Gamma Motor Neurons |
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What are Alpha Motor Neurons Responsible for?
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Muscle Contraction
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What are Gamma Motor Neurons Responsible for?
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Muscle Spindle Control
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What are Ia and IIa Fibers Responsible for?
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Muscle Spindle Afferents
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What type of Neurons Control Muscle Contraction?
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Alpha
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What type of Neurons Control Spindle Contraction?
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Gamma
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What is Gamma Coactivation? What is Activated? What does the Activating?
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-Muscle Spindle Fibers are Activated at the Same time as Muscle Contraction Fibers
-Alpha and Gamma Motor Neurons are Both Activated -Sensory Afferents |
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Where are Golgi Tendon Organs Found? What are they connected to and how?
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-In Tendons
-In Series with Extrafusal Fibers |
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What kind of Connection do Muscle Spindles make with Muscles?
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Parallel
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What type of Fibers Innervate the GTO?
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Ib Fibers
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What function does the GTO have? How does it do this?
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-Relaxes the Agonist Muscle and Facilitates the Antagonist
-Ib Fibers go to the Ventral Horn -Activate Interneurons -Inhibit Alpha Motor Neurons of Muscle that is acting |
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What Muscle Receptor Acts via Negative Feedback on Agonists Muscles and Facilitates Antagonists? What type of Fibers are used? What type of neuron does this? What type of Neuron is Inhibited?
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-GTO
-Ib Fibers -Interneurons -Alpha Motor Neuron |
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When Stretch Receptors Fire, what is a muscle going to want to do?
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-Contract to Counteract
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What is a Clonus? How can this result? What is this often a sign of?
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-Rapid Trembling of a Muscle
-Stretch and Contract Systems get stuck in a loop -Damage or Extreme Fatigue |
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What do Absent Reflexes Indicate? What type of Damage is this associate with?
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-Lesion in Reflex Arc
-LMN |
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What is a Fasciculation? Why does it happen? Is it visible?
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-Muscle Twitch
-May be a Disorder, May be from LMN dying -Yes |
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What might a LMN Lesion cause?
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Fasciculations
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What is Neurogenic Atrophy? What type of Lesion might it result from?
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-Muscle Wasting, Loss of Tropic Factors
-LMN |
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What is a Fibrillation? What may cause this? Can it be seen?
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-Twitches of Single Muscle Fibers
-Denervation of a Muscle Fiber -Too small to see with the Naked Eye |
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If a patient comes in with Flaccidity of their muscles, what type of Lesion would you expect?
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-LMN or Acute UMN
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If a patient comes in with Flaccidity of their muscles and they say that they've had if for awhile, what type of Lesion would you expect? Why?
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-LMN Lesion
-Flaccidity can be from LMN or Acute UMN Lesions -If its been awhile, this rules out the UMN Lesion because over time, this would result in Spasticity |
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A Patient comes in with Areflexia. What type of Lesion might they have?
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LMN or Acute UMN
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What will UMN Damage eventually lead to?
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Increased Muscle Stretch Reflexes
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A patient comes in with Hyperreflexia. What type of Lesion might they have?
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UMN
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You suspect a patient has a Lesion. They have no Clonus. What type of Lesion do you think it is?
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LMN or Acute UMN
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You suspect a patient has a Lesion. They have Clonus. What type of Lesion do you think it is?
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UMN
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What is Clasp-Knife Rigidity or Spastic Catch? What is Associated with?
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-Resistance to Passive Movement of a Joint when Spasticity is Present: Muscles first resist movement strongly and then resistance melts away
-UMN Damage |
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You suspect a patient has a Lesion. They have Spasticity in their Muscles. What causes this? What type of Lesion do you think it is?
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-Excessive Muscle Tone due to Hyperactive Stretch Reflexes
-UMN |
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You suspect a patient has a Lesion. They have Flaccidity in their Muscles. What type of Lesion do you think it is?
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LMN or Acute UMN
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If an Adult Patient shows a Babinski Reflex, what type of Damage are they likely to have?
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UMN
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What type of Atrophy could result from an UMN Lesion? LMN Lesion?
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-Disuse Atrophy
-Neurogenic Atrophy |
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What usually causes Presynaptic Disorders?
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-Decreased Ability to Release NT
-Uncontrolled Release of NT until the Terminal is Depleted |
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What is a Larger Response with Repeated Stimulation associated called? What types of disorders is this associated with?
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-Warm-up Phenomenon
-Presynaptic Disorders |
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What is Warm-Up Phenomenon?
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Larger Response with Repeated Stimulation
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What causes Lambert-Eaton Myasthenic Syndrome?
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-Autoimmune Disorder
-Abs produced against Voltage Dependent Calcium Channels |
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What are some Symptoms of LEMS (Lambert-Eaton Myasthenic Syndrome)?
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-Muscle Weakness and Fatigue that Improves with Exercise
-Diminished Reflexes -Autonomic Dysfunctions: Dry Mouth, Impotence, Hypotension |
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What is LES? What basically happens?
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-Lambert-Eaton Myasthenic Syndrome
-Prevents Ca2+ Entry and NT Release |
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A patient comes in complaining about Muscle Weakness and Fatigue that improves with exercise, diminished reflexes, dry mouth, and impotence. What might be have?
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LEMS - Lambert-Eaton Myasthenic Syndrome
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How is LEMS treated?
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-Plamophoresis to Remove IgGs
-Suppress the Immune System |
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Why isn't NT released in a patient suffering from Lambert-Eaton Myasthenic Syndrome?
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-Abs are produced against Voltage Gated Calcium Channels
-These Channels are needed for NT Release |
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What are Postsynpatic Disorders frequently the cause of?
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Decreased Availability of ACh Receptor on the Motor Endplate
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A doctor tells you that a patient has decreases availability of ACh on the Motor Endplate. What type of disorder might they have?
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A Postsynpatic Disorder
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What are most Postsynaptic Disorders characterized by?
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-Smaller Response with Repeated Stimulation
-Fatiguability |
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What type of Disorder is MG?
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Postsynaptic
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What is Myasthenia Gravis?
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-Abnormal Muscle Fatiguability
-Usually Slow Progressive, Affecting Muscles of the Head First -Autoimmune Disease - Develop Abs which attack ACh Receptors on the Muscle -Impaired Motor Commands to Muscle -Most Often Strikes Younger Women and Older Men |
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How does MG result?
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-Autoimmune Disease
-Abs attack ACh receptors on the Muscle |
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What results in MG?
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-Impaired Motor Commands to the Muscle
-Abnormal Muscle Fatiguability and Weakness |
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What type of Muscles are usually affected first in MG?
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Head
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No Sensory Involvement in MG
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No Sensory Involvement in MG
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What are Nerve Conduction Studies?
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Studies of the Waveforms Generated in the PNS
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In which part of the Nervous System are Nerve Conduction Studies done?
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PNS
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How are Motor Nerve Conduction Studies done?
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Stimulation of a Peripheral Nerve while Recording from a Muscle Innervated by that Nerve
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How are Sensory Nerve Conduction Studies done?
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Stimulation of a Mixed Nerve while Recording from a Mixed or Cutaneous Nerve
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What is the F Wave in NCS? What is used to asses?
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-Represents the Activation of a Motor Nerve and Subsequent Conduction towards the SC and Return of Conduction back "down" the Nerve
-Almost like a Motor Arc -More Proximal Segments of a Peripheral Motor Nerve |
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What is the H-Reflex in NCS? What is used to Asses?
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-Due to a Spinal Reflex
-Represents the Activation of a Sensory Nerve with Subsequent Conduction towards the SC and Return of Conduction back "down" the Motor Nerve -Conduction along the Proximal Segment of Sensory Fibers and the Entire Length of the Motor Fibers |
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How is the function of More Proximal Segments of a Peripheral Motor Nerve tested?
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F-Wave in NCS
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How is the Conduction along the Proximal Segment of Sensory Fibers and the Entire Length of the Motor Fibers tested?
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H-Reflex in NCS
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What Represents the Activation of a Sensory Nerve with Subsequent Conduction towards the SC and Return of Conduction back "down" the Motor Nerve?
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H-Reflex in NCS
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What Represents the Activation of a Motor Nerve and Subsequent Conduction towards the SC and Return of Conduction back "down" the Nerve?
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F-Wave in NCS
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What supplies Blood to the Midbrain?
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Posterior Cerebral Artery
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What supplies Blood to the Midbrain?
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Posterior Cerebral Artery
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What supplies Blood to the Midbrain?
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Posterior Cerebral Artery
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What supplies blood to the Pons?
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Basilar Artery
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What supplies blood to the Pons?
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Basilar Artery
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What supplies blood to the Medial Medulla?
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Anterior Spinal Artery
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What supplies blood to the Medial Medulla?
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Anterior Spinal Artery
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Epidural Hematoma
Lens Shaped Middle Meningeal Artery |
Epidural Hematoma
Lens Shaped Middle Meningeal Artery |
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Subdural Hematoma
Crescent Shaped Bridging Veins |
Subdural Hematoma
Crescent Shaped Bridging Veins |
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Subarachnoid Hemorrhage
Worst Headache of my life Rupture of a weakened vessel in the Pial Wall |
Subarachnoid Hemorrhage
Worst Headache of my life Rupture of a weakened vessel in the Pial Wall |
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Where is Parasympathetic Output found?
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Cranial Nerves and S2-S4
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Where is Sympathetic Output found?
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T1-L2
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On which side is Autonomic Innervation from?
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Ipsalateral
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