The nervous pathway SHANDONG UNIVERSITY Liu Zhiyu

1. The nervous pathwaySHANDONG UNIVERSITY Liu Zhiyu

2. 一、 Sensory Pathways

3. proprioceptive and fine touch pathway of trunk and limbs

4. 1. proprioceptive and fine touch pathway of trunk and limbs Primary Neuron • Cell bodies are located in the ganglion of spinal n. • transmit sensory input from joint, muscle, tendon to the posterior funiculus of the spinal cord • form the Fasciculus cuneatus and Fasciculus gracilis

5. 1. proprioceptive and fine touch pathway of trunk and limbs • Secondary Neuron • Cell bodies are located in Nucleus gracilis and Nucleus cuneatus • Send out fibers Cross to the opposite by decussation of medial lemniscus • Ascends as medial lemniscus • Third Neuron • cell bodis are located in the thalamus • send out fibers to form central thalamic radiation project to the somatic sensory cortex

6. VPL nucleus central thalamic radiations Medial lemniscus Decussation of medial lemniscus Nucleus gracilis Nucleus cuneatus Fasciculus cuneatus Spinal ganglion Fasciculus gracilis III II I

7. Fasciculus gracilis (below T5) Decussation of medial lemniscus medial lemniscus Fasciculus cuneatus (above T4) II central thalamic radiations Posterior limb of internal capsule 1. proprioceptive and fine touch pathway of trunk and limbs Spinal ganglion muscles,tendons,joints and periosteum Central processes Peripheral processes ipsilateral posterior funiculus of spinal cord I Receptor for fine touch in skin Gracile nucleus cuneate nucleus ventral posterolateral nucleus (VPL) supeior 2/3 of postcentral gyrus and posterior part of the paracentral lobule, Precentral gyrus III

8. Pain,temperature and simple touch pathway of trunk and limbs

9. central thalamic radiations ventral posterolateral nucleus Spinal lemniscus Ⅰ、Ⅳ、Ⅶ of posterior horn spinothalamic tract spinal ganglia III II I

10. Pain,temperature and simple touch pathway of trunk and limbs • Primary Neuron • Cell bodies are located in the ganglion of spinal n. • Relay sensory input from the periphery to the posterior horn of the spinal cord • Synapses with the secondary neurons in the posterior horn of spinal cord

11. Pain,temperature and simple touch pathway of trunk and limbs • Secondary Neuron • located in the Ⅰ、Ⅳ、Ⅶ ofposterior horn of spinal cord • Send out fibers cross to the opposite side through the anterior white commissures and form the spinothalamic tract • Third Neuron • the third neurons located in the thalamus • send out fibers to form central thalamic radiation project to the somatic sensory cortex

12. Pain,temperature and simple touch pathway of trunk and limbs Central processes Posterior root central thalamic radiations Posterior limb of internal capsule Spinal ganglion Skin exteroceptor Peripheral processes I Ⅰ、Ⅳ、Ⅶ of posterior horn Ascending 1 - 2 segments lateral spinothalamic tract (pain and temperature) II anterior spinothalamic tract(simple touch) ventral posterolateral nucleus (VPL) supeior 2/3 of posterior gyrus and posterior part of the paracentral lobule III

13. Pain, temperature and simple touch pathway of head and face

14. ventral posteromedial nucleus (VPM) pontine nucleus of trigeminal n central thalamic radiations trigeminal ganglion trigeminal lemniscus Spinal tract of trigeminal n. spinal nucleus of trigeminal n. III II I

15. Pain,temperature and simple touch pathway of head and face central thalamic radiations Posterior limb of internal capsule trigeminal ganglion Skin and mucosa of head and face Central processes Trigeminal n. Peripheral processes Root of trigeminal n. I ventral posteromedial nucleus (VPM) pontine nucleus of trigeminal n. trigeminal lemniscus II spinal nucleus of trigeminal n. III inferior 1/3 of posterior gyrus

16. Spinal ganglion receptor cortex of paleocerebellum

17. （三）visual pathway

18. Optic n. Optic chiasma Decussation of fibers from nasal halves of retina Optic tract Fibers from temporal halves of retina uncrossed （三）visual pathway receptor ganglion cell bipolar cell cone cell rod cell Lateral geniculate body Optic Radiation Both banks of calcarine sulcus

19. ① Blindness of eye of corresponding side bitemporal hemianopia of visual field ② Blindness in nasal half of visual field of corresponding side ③ ④ Homonymous hemianopia of visual field in both eye

20. Ciliary ganglion Oculumotot n. E-W nucleus Pretectal region 2. pupillary reflexes retina Contraction of pupil Optic n. Sphincter pupillae Optic chiasma Postganglionic fibers Optic tract Ciliary ganglion Brachium of superior colliculus Oculumotot n. accessory nuclei of III Pretectal region

21. 2. pupillary reflexes

22. medial geniculate body acoustic radiation inferior colliculus cochlear nuclei Spiral organ cochlear ganglion The acoustic(auditory) pathway

23. The acoustic(auditory) pathway cochlear nuclei cochlear ganglion Trapezoid body Spiral organ Cochlear nerve Lateral lemniscus medial geniculate body inferior colliculus acoustic radiation transverse temporal gyri Brachium of inferior colliculus Posterior limb of internal capsule

25. VPL nucleus central thalamic radiations Medial lemniscus Nucleus gracilis Nucleus cuneatus Decussation of medial lemniscus Fasciculus cuneatus Spinal ganglion Fasciculus gracilis III II I

26. central thalamic radiations ventral posterolateral nucleus Spinal lemniscus Ⅰ、Ⅳ、Ⅶ of posterior horn spinothalamic tract spinal ganglia III II I