Spinal Chord Flashcards
What are the 3 Maters (layers) on the spinal chord?
Dura
Arachnoid
Pia
How many paired nerves are there?
31 Paired Nerves
What is the Filum Terminale Externum?
Bundle of Spinal cord coverings
Anchors spinal cord in the Coccyx
What is the Coccyx?
Tailbone
End of bone
Grey Matter
Cell bodies and neurons
What are the first 3 segments of nerves in the spine?
Cervical Nerves
Thoracic Nerves
Lumbar Nerves
What is the Cervical Enlargement?
Larger section of spine to accommodate arms
How many nerves for the ribs?
24 nerves for the 24 ribs
What is the Thoracolumbar Enlargement?
Larger section of spine to accommodate legs
Where is the termination of the Spinal Cord?
Cauda Equina (tail)
What is the Meissner’s Corpuscle Receptor for?
Touch
What is Pacinian Corpuscle Receptor for?
Pressure
Dorsal Ganglia
Group of Neurons
Funiculus
White Matter
Ventral Funiculus
Pain + Temperature
Lateral Funiculus (motor columns)
Carry info to spinal chord
Dorsal Funiculus
Gracile + Cuneate Funiculus
Carries discriminative sensation information
What sensory info does the Gracile Funiculus have?
Legs
What sensory info does the Cuneate Funiculus have?
Arms
Substantia Gelatinosa
Transport
Jelly-like
Nucleus Proprius
Discriminative Sensory Information
Monosynaptic/Myotatic
Reflex Arc
Anterior White Commissure
Bundle of white matter
Left to Right
Dessucation
Crossing Over
What is the pathway of Discriminative Sensation?
Dorsal Column Pathway
Synapses at the Cuneate Nucleus and then Crosses Over to become Medial Lemniscal
Goes to synapse in Thalamus
Goes through Internal Capsule up to Primary Sensory Cortex
What is the pathway of the Spinothalamic Tract (pain + temp)?
Synapse in the Substantia Gelatinosa
Decussate in anterior white commissure
Synapse in Thalamus
Go through internal capsule to primary sensory cortex
What happens if you have damage in the medial lemniscus (upper touch + pressure)
Lose touch + pressure on opposite side
What happens if you have damage in the Spinothalamic (upper pain + temp)
Lose Pain + temp on opposite side
What happens if you have damage in the medial lemniscus (lower touch + pressure)
Loss of sensation on same side with touch and pressure
Associative Sensory Loss
Both tracts are affected
Dissociative Sensory Loss
Only one track is affected
What does the Basal ganglia help with?
Helps control mood through movement
Slowly controlled refined movement
What happens if there is damage to the upper motor neurons of the Corticospinal Tract?
Causes Spasticity
Too much control
Becomes stiff and rigid
What happens if there is damage to the lower motor neurons of the Corticospinal Tract?
Flaccid Paralysis
No neural control in muscle
Upper Motor Neurons (Corticospinal)
Movement Control
Lower Motor Neurons (Corticospinal)
Reflexes
In the Corticospinal, what are the neurons that stay on the same side for?
Control axial muscles
What are the 5 parts of the Basal Ganglia?
Caudate Nucleus
Putamen
Globus Pallidus
Subthalamic Nucleus
Substantia Nigra
Glutamate
Major excitatory neurotransmitter
Fires up the neurons in the striatum
What happens in the motor system?
- Glutamate fires up the neurons in the striatum
- Acts on Dopamine or GABA
- Dopamine activates the inhibitory neurons
- Inhibition happens on excitatory neurons which sends messages up to the cerebral cortex
What happens in parkinson’s disease?
-Neurons not primed and ready to go
- Glutamate starts to build up which is very toxic
- Also means that no inhibition is happening on inhibitory neurons. Dopamine levels go down too
- Therefore the inhibitory neurons are firing more and more and acting on the excitatory neurons
-Brings excitation down (Hypo excitation)
- End up with stiffness + rigidity
What does Cerebellum help with?
Stopping a movement
Where is Dopamine housed?
Substantia Nigra
Levodopa
Precursor to dopamine
Helps dopamine levels go up
