1. The Cerebellum 小 脑

2. Position: lies above and behind the medulla oblongata and pons;
occupies posterior cranial fossa
Cerebellum

3. External features Three peduncles 三对脚
Inferior cerebellar peduncle 小脑下脚
connect with medulla and spinal cord, contain both afferent and efferent fibers

4. External features Three peduncles 三对脚 Middle cerebellar peduncle 小脑中脚
connect with pons, contain afferent fibers
Superior cerebellar peduncle小脑上脚
connect with midbrain, contain mostly efferent fibers

5. External features Tonsil of cerebellum 小脑扁桃体:
two elevated masses on inferior surface of hemisphere, just nearby foramen magnum

6. Lobes of cerebellum Two deep fissures Primary fissure 原裂
Posterolateral fissure 后外侧裂
Three lobs
1. Flocculonodular lobe绒球小结叶:
flocculus 绒球 and nodule 小结
2. Anterior lobe
3. Posterior lobe
corpus of cerebellar
小脑体

7. Lobes Anterior lobe corpus of Cerebellum 小脑体 Primary fissure
Posterior lobe
nodule 小结
Flocculus 绒球
Flocculonodular lobe
绒球小结叶
Posterolateral fissure

8. Ⅱ. Internal structures Gray matter Cerebellar cortex 小脑皮质
Cerebellar nuclei 小脑核
Dentate nucleus 齿状核
Fastigial nucleus 顶核
Interposed nuclei 中间核
Emboliform nucleus 拴状核
Globose nucleus 球状核

9. Ⅱ. Internal structures White matter— medullary center小脑髓体
Cerebellar cortex
Fastigial nucleus
Globose nucleus
Dentate nucleus
Emboliform nucleus
medullary center

10. Three functional divisions
Spinocerebellum 脊髓小脑( paleocerebellum 旧小脑) :
vermis and intermediate zone
Cerebrocerebellum 大脑小脑(neocerebellum 新小脑):
lateral zone
Vestibulocerebellum 前庭小脑 ( archicerebellum原小脑): Flocculonodular lobe and vestibular nuclei
vermis
intermediate zone
lateral zone
Flocculonodular lobe

11. Middle cerebellar peduncle 小脑中脚
Ⅲ. Connections and peduncles of cerebellum
Middle cerebellar peduncle 小脑中脚
is composed of fibres which arises in the opposite side of the pontine nuclei and pass to the erebellum, transmit impulses which reach the the pons from the cerebral cortex.

12. inferior cerebellar peduncle 小脑下脚
Ⅲ. Connections and peduncles of cerebellum
inferior cerebellar peduncle 小脑下脚
This peduncle consists mainly of afferent fibres to the cerebellum，inlude
posterior spinocerebellar tract；
the fibers from the inferior olivary nucleus,
the fibers from vestibular
nuclei and nerve.
It also transmits efferent fibres to the medulla oblongata.

13. superior cerebellar peduncle 小脑上脚
Ⅲ. Connections and peduncles of cerebellum
superior cerebellar peduncle 小脑上脚
This is the principal efferent pathway from the cerebellum, its fibres arises mainly from the dentate nucleus齿状核, and passes anterosuperiorly to the opposite thalamus丘脑 and red nucleus of the midbrain.

14. IV. Connections and function of cerebellum
Vestibulocerebellum 前庭小脑
Afferents fibers 传入纤维: receive input from vestibular nuclei and vestibular n..
Efferents fibers 传出纤维:
to the vestibular nucleus
→ vestibulospinal tract → anterior horn.of spinal cord.
→ medial longitudinal fasciculus 内侧纵束→ motor nuclei asociated with movement of eyeball。
Function: involved in eyeball movements and maintain the balance of the body

15. IV. Connections and function of cerebellum
Spinocerebellum 脊髓小脑
Afferent fibers:
receive somatic sensory information via spinocerebellar tracts.
Efferent fibers:
to the fastigial nucleus顶核→ vestibular nuclei → vestibulospinal tract → motor neurons of anterior horn

16. IV. Connections and function of cerebellum
Spinocerebellum 脊髓小脑
Efferent fibers:
to the interposed nuclei中间核 →
① contralateral red nucleus → rubrospinal tract →motor neurons of anterior horn of spinal cord
② contralateral thalamus对侧丘脑→cerebral cortex大脑皮质

17. IV. Connections and function of cerebellum
Spinocerebellum
Function:
play an important role in control of muscle tone and coordination of muscle movement on the same side of the body

18. IV. Connections and function of cerebellum
Cerebrocerebellum
Afferents: receives input from the cerebral cortex via the pontine nuclei middle cerebellar peduncle
Efferents: to dentate nucleus 齿状核→ contralateral thalamus → primary motor cortex → corticospinal tract → motor neurons of anterior horn
Function: coordination of muscle movement of limbs.