INTRODUCTION
Sensory tracks formed in the spinal cord by sensory fibers from receptors and ready higher centers in CNS are called Ascending tracks
a sensory input passes through the spinal cord, medulla and thalamus to reach CNS
spinal cord, medulla and thalamus are called relay stations
Ascending tracks carry various sensations through relay stations to the CNS
they are present in the white matter of the spinal cord
NEURAL COMPOSITION OF ASCENDING TRACKS
they have a chain of successive neurons
First-order neuron
cell bodies reside in the dorsal root ganglion
carries information from the receptor to the spinal cord
they don't relay sensation on face
they synapse with the second-order neuron
Second-order neuron
nucleus present in the dorsal horn of the spinal cord
they ascend and transmits the impulse to the thalamus or cerebellum
Third-order neuron
located in thalamus
conducts sensory impulse to the somatosensory cortex
it contains two types of tracks
specific ascending track
non- specific ascending track
SENSORY TRACKS
1. dorsal collum
- track of goll (fasciculus gracillis)
- track of burdach (fasciculus cuneatus)
2. lateral column
- lateral spinothalamic track
- dorsal spinocerebellar track
- ventral spinocerebellar track
- spinotectal track
- spino- olivary track
- spinovestibular track
- spinopontine track
- spinoreticular track
3. ventral (anterior) collum
- anterior spinothalamic track
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