Ascending tracts of spinal cord
| Situation | Tract | Origin | Course | Termination | Function |
| Anterior white funiculus | 1.Anterior spinothalamic tract | Chief sensory cells | Crossing in spinal cord, forms spinal lemniscus | Ventral posterolateral nucleus of thalamus | Crude touch sensation |
| Lateral white funiculus | 2. Lateral spinothalamic tract | Substantia gelatinosa | Crossing in spinal cord, forms spinal lemniscus | Ventral posterolateral nucleus of thalamus | Pain and temperature sensations |
| 3. Ventral spino-cerebellar tract | Marginal cells | Crossing in spinal cord | Anterior lobe of cerebellum | Subconscious kinesthetic sensations | |
| 4. Dorsal spino-cerebellar tract | Clarke's column cells | Uncrossed fibers | Anterior lobe of cerebellum | Subconscious kinesthetic sensations | |
| Spinotectal tract | Chief sensory cells | Crossing in spinal cord | Superior colliculus | Concerned with spinovisual reflex | |
| 6.Fasciculus dorsolateralis | Posterior nerve root ganglion | Component of lateral spinothalamic tract | Substantia gelatinosa | Pain and temperature sensations | |
| 7. Spinoreticular tract | Intermedio- lateral cells | Crossed and uncrossed fibers | Reticular formation of brainstem | Consciousness and awareness | |
| 8.Spino-olivary tract | Not specific | Uncrossed fibers | Olivary nucleus | Proprioception | |
| 9.Spino-vesti- bular tract | Not specific | Crossed and uncrossed fibers | Lateral vestibular nucleus | Proprioception | |
| Posterior white funiculus | 10.Fasciculus gracilis | Posterior nerve root ganglia | Uncrossed fibers. No synapse in spinal cord | Nucleus gracilis in medulla | Tactile sensation. Tactile localization. Tactile discrimination. Vibratory sensation. Conscious kinesthetic sensation. Stereognosis. |
| 11.Fasciculus cuneatus | Posterior nerve root ganglia | Uncrossed fibers. No synapse in spinal cord | Nucleus cuneatus in medulla |
Descending tracts of spinal cord
| Tract | Situation | Origin | Course | Function | |
| Pyramidal tracts | 1. Anterior corticospinal tract | Anterior white funiculus | Betz cells and other cells of motor area | Uncrossed fibers | 1. Control of voluntary movements. 2. Upper motor Neurons functions
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| 2. Lateral corticospinal tract | Lateral white funiculus | Betz cells and other cells of motor area | Crossed fibers | ||
| Extra-pyramidal tracts | 1. Medial longitudinal fasciculus | Anterior white fasciculus | Vestibular nucleus. Reticular formation. Superior colliculus and cells of Cajal | Uncrossed fibers. Extend up to upper cervical segments | 1. Coordination of reflex ocular move- ments. 2. Integration of movements of eyes and neck. |
| 2. Anterior vestibulo- spinal tract | Anterior white funiculus | Medial vestibular nucleus | Uncrossed fibers. Extend up to upper thoracic segments | 1. Maintenance of muscle tone and posture. 2. Maintenance of position of head and body during acceleration | |
| 3. Lateral vestibule- spinal tract | Lateral white funiculus | Lateral vestibular nucleus | Mostly un- crossed. Extend to all segments | ||
| 4. Reticulo- spinal tract | Lateral white fasciculus | Reticular formation of pons and medulla | Mostly un- crossed. Extend upto thoracic segments | 1. Coordination of voluntary and reflex movements. 2. Control of muscle tone. 3. Control of respi- ration and blood vessels | |
| 5. Tectospi- nal tract | Anterior white funiculus | Superior colliculus | Crossed fibers. Extend up to lower cervical segments. | Control of movement of head in response to visual and auditory impulses | |
| 6. Rubro- spinal tract | Lateral white funiculus | Red nucleus | Crossed fibers. Extend up to thoracic seg- ments. | Facilitatory influence on flexor muscle tone | |
| 7. Olivo- spinal tract | Lateral white funiculus | Inferior olivary nucleus | Mostly crossed. Extent—not clear. | Control of movements due to proprioception | |
| Termination — Fibers of all the tracts terminate in motor neurons situated in the anterior gray horn of spinal cord | |||||
Sensory pathways
| Sensation | Receptor | First order neuron in | Second order neuron in | Third order neuron in | Center |
| Fine touch | Posterior nerve root ganglion | Nucleus gracilis and | |||
| Tactile localization, tactile discrimination, vibratory sensation, stereognosis. | Meissner's corpuscles and Merkel's disc | Ganglion – Fibers form fasciculus gracilis and fasciculus cuneatus | Nucleus cuneatus- Internal arcuate fibers | Ventral postero- lateral nucleus of thalamus | Sensory cortex |
| Pressure, crude touch | Pacinian corpuscle | Posterior nerve root ganglion | Chief sensory cells- Fibers form anterior spinothalamic tract | Ventral postero- lateral nucleus of thalamus | Sensory cortex |
| Temperature | Warmth- Raffini's end bulb, cold-Krause's end bulb | Posterior nerve root ganglion | Substantia gelatinosa-Fibers form lateral spinothalamic tract | Ventral postero- lateral nucleus of thalamus | Sensory cortex |
| Conscious kinesthetic sensation | Proprioceptors— muscle spindle, Golgi tendon apparatus, etc. | Posterior nerve root ganglion- -Fibers form fasciculus gracilis and fasciculus cuneatus. | Nucleus gracilis and nucleus cuneatus— Internal arcuate fibers | Ventral postero- lateral nucleus of thalamus | Sensory cortex |
| Subcon- scious kine-sthetic sensation | Proprioceptors— muscle spindle, Golgi tendon apparatus, etc. | Posterior nerve root ganglion | Clarke's column of cells and marginal cells— Fibers form dorsal and ventral spinocerebellar tracts | Cerebel- lum | |
| Pain | Free nerve endings | Posterior nerve root – Ganglion – Fast pain – A 5 fibers Slow pain – С fibers | Fast pain—marginal cells in spinal cord. Slow pain-substantia gelatinosa | Ventral postero- lateral nucleus of thalamus. Reticular forma- tion and midbrain | Sensory cortex |
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