Neurology anatomy Flashcards
The Dorsal Column/Medial Lemniscus System
• Fine touch and conscious proprioception (particular from the upper limb).
Dorsal Column/Medial Lemniscus System cross at?
medulla
fasciculus gracilis (nucleus gracilis)
lower half of the body
fasciculus cuneatus
upper limbs and torso
The Dorsal Column/Medial Lemniscus System 2nd pathway called?
medial lemniscus
medial lemniscus synapses where?
ventral posterolateral nucleus, or VPL
Spinothalamic Tract
pain, temperature, deep pressure, crude touch
Spinothalamic Tract cross over occur
one or two vertebrae above or below within Lissauers fasciculus
anterior white commissure
second neuron cell body in the dorsal horn of Spinothalamic Tract
substantia gelatinosa
anterior spinothalamic tract
crude touch
lateral spinothalamic tract
pain and temperature
Spinocerebellar pathway
unconscious proprioceptive information to the cerebellum, in order to coordinate posture and the movement of the lower limb and upper limb musculature.
Spinocerebellar pathways 3 types
Dorsal/posterior spinocerebellar
Cuneocerebellar
Ventral/anterior spinocerebellar
Corticospinal tract
Fine, precise movement, particularly of distal limb muscles (e.g. digits and piano).
Corticospinal tract crosses?
Pyramids on the medulla
- crossed form lateral CST - distal muscles
- Uncrossed form Ventral CST (cross segmentally)
damage to corticospinal tracts causes?
UMN signs
Rubrospinal tract:
red nucleus in the midbrain.
It excites flexor muscles and inhibits extensor muscles of the upper body.
Corticobulbar Tract
upper motor neurone of the cranial nerves, to provide innervation of the face, head and neck. They innervate cranial motor nuclei bilaterally; however, two exceptions are the hypoglossal nuclei and lower facial nuclei which are innervated contralaterally only.
This includes fibres to the motor nuclei of CN’s V, VII, X, and XII.
Tectospinal tract
mostly to cervical segments.
Thought to mediate reflex head and neck movement due to visual stimuli.
Begins in the superior colliculus in the mid brain (posterior portion: tectum (means roof): behind cerebral aqueduct
It co-ordinates movements of head and neck to vision stimuli.
Close relationship with visual system
Reticulospinal Tract
- forms the central core of the brainstem.
- Originates from the reticular formation in the medulla and pons:
- It has many nuclei and receives input from virtually all parts of the CNS
- Fibres originating in pons facilitate extensor movements and inhibit flexor movements,
- The medullary reticulospinal tract inhibits extensor and facilitates flexor.
Vestibulospinal Tract
- Excitatory input to “antigravity” extensor muscles.
- Fibres originate in the vestibular nuclei of pons and medulla (these in turn receive input from vestibular apparatus and cerebellum).
