Neuroanatomy L1 Central Pattern Generators and Locomotion Flashcards
Movement planning begins in the_____ cortices, then the axon leaves the primary motor cortex extends down the ______ tracts to the _____ for cranial nerves or ______ for peripheral nerves. Collaterals are sent to the ______ tracts.
motor; pyramidal; brainstem; spinal cord; extra-pyramidal
Descending fibres are located in the _____ funiculus (pyramidal pathway), and synapse on a motor neuron in the _____ horn of the grey matter in the ______. The axon then extends to the ____ to innervate the muscle.
lateral; anterior; spinal cord; periphery
Sometimes we directly exert ____ control over movement of muscles - ie. climbing on rocks or tapping your fingers to the thumb. But for highly stereotyped behaviours (ie. walking or reflexes) there are ________ that induce movements that are controlled at the level of the spinal cord.
cortical; central pattern generators
Most of the CPG are _____, and all is needed is a _______ command from the brain that excites the group of neurons. Give an example.
interneurons; descending motor
- Eg. A headless chicken with an intact brainstem was still able to walk and stand due to central pattern generators
If there is a lesion in the internal capsule you have a ____ based response due to the dominant action of the ____ tract.
flexor; rubrospinal
If there is a lesion below the red nuclei there is an _______response.
extensor
A lot of spinal cord lesions due to accidents involve a _____ displacement of the vertebra which compromises the ____ spinal cord - thus we see damage to the _____ tract - loss of voluntary motor control.
sideways; lateral; corticospinal
The spinal cord is not just a conduit, it is capable of _____ processing.
complex

Medial and ventral is the ____ limb.
Proximal limb

Lateral and dorsal is the _____ limb.
Distal limb

Flexors are more _____ and _____.
medial; posterior

Extensors are more ____ and _____.
lateral; anterior

There is somatotopic organisation in the grey matter of the spinal cord. Proximal muscles are _____ (medial/lateral), and distal muscles are _____(medial/lateral). The extensors are ____ (anterior/posterior), and flexors are ___ (anterior/posterior).
medial; lateral; anterior; posterior

There are continuous columns of _______ up and down the spinal cord - they are not broken up, it is a continuum. The motor neurons are interconnected with___neurons and ______ neurons that forms the basis for reflex arcs.
neuron cell bodies; inter; sensory

What is Rexed’s laminae?
Dividing the spinal cord in 10 zones based on cytoarchitecture (cell distribution and shape)

How was the Rexed’s laminae formed?
Described them based on how they looked under a microscope with a certain staining on of the section.

Research indicates that the central pattern generators are located in rexed lamina _____.
7

Where does sensory input pass through?
Sustantia gelatinosa (2)

How does Rexed’s laminae relate to function?
cells look different because they serve different functions

What Rexed’s lamina is intermediate grey?
Rexed’s lamina 7

What is intermediate grey (Rexed’s lamina 7) associated with?
Associated with modulator reflex arcs and central pattern generators.
Crucial area for locomotion, and may have therapeutic potential for rehabilitation. Induces purposeful movements

What Rexed’s lamina are motor neurons (anterior horn)?
Lamina 9

What horn are motor neurons found in?
Anterior horn

What horn is substantia gelantinosa found in?
Posterior horn



















































