Transcript The Cerebellum

The Cerebellum
Position

Lies above and behind the
medullar and pons and
occupies posterior cranial
fossa
Cerebellum
External features
Consists of two cerebellar hemisphere united in the
midline by the vermis
Lobs
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Two deep fissures
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Primary fissure
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Posterolateral fissure
Three lobs
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Flocculonodular lobe 叶
flocculus and nodule
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Anterior lobe
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Posterior lobe
Corpus of
cerebellar
Internal structures
Cerebellar cortex
Fastigial nucleus
Globose nucleus
Dentate nucleus
medullary center
Emboliform nucleus
Connections and function of cerebellum
Vestibulocerebellum

Function: involved in eye movements and
maintain balance
Connections and function of cerebellum
Spinocerebellum
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Function: play an important role in control
of muscle tone and coordination of
muscle movement on the same side of
the body
Connections and function of cerebellum
Cerebrocerebellum
 Function: participates in planning movements
The Diencephalon
Position
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Position: Lies between midbrian and cerebrum, almost
entirely surrounded by cerebral hemisphere
Subdivision
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Doral thalamus背侧丘脑
Metathalamus后丘脑
Epithalamus上丘脑 Subthalamus底丘脑 Hypothalamus下丘脑
Dorsal thalamus
External features
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A large egg-shaped
nucleus mass,
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Anterior end called
anterior thalamic tubercle,
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Posterior end called
pulvinar
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Right and left portion of
thalamus are joined by
interthalamic adhesion
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Floor－hypothalamic
sulcus
Three nuclear group－divided by internal
medullary lamina
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Anterior nuclear group internal medullary lamina
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Medial nuclear group
Med. nuclear group
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Lateral nuclear group
Dorsal tier
Ant. nuclear group
Pulvinar
Medial geniculate
body (MGN)
Ventral anterior
Ventral intermediate
Ventral posterior nucleus (VP)
Lateral geniculate body (LGN)
Ventral posterolateral (VPL)
Ventral posteromedial (VPM )
Subdivision
Principal Nuclei
Common
abbreviation
Ant. nuclear group
Med. nuclear group
Lat. nuclear group
Dorsal tier
Lateral dorsal
LD
Lateral posterior
LP
Pulvinar
Ventral tier
Ventral anterior
VA
Ventral intermediate
VI
Ventral posterior
VP
Ventral posterolateral
VPL
Ventral posteromedial
VPM
Special relay nuclei
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Vent. anterior nucleus (VA)
Vent. intermediate nucleus (VI)
Receiving dentate nucleus, globus pallidus and substantia nigra to
motor cortex
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Vent. posteromedial nucleus (VPM) －receives
trigeminal lemniscus and teste fibers
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Vent. posterolateral nucleus (VPL) －receives medial
lemniscus and spinal lemniscus
Projects to first somatic sensory area via central thalamic radiation
Metathalamus后丘脑
Lateral geniculate body (LGN)
Medial geniculate body (MGN)
Metathalamus
Metathalamus
Medial geniculate body
(MGN)
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Relay station of audition
Receive fibers from
inferior colliculus
Projects to auditory area
via acoustic radiation
Lateral geniculate body
(LGN)
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Relay station of vision
Receive fibers from optic
tract
Projects to visual area via
optic radiation
Hypothalamus
Position－lies ventral to thalamus
Boundaries
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Superiorly:
hypothalamic sulcus
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Inferiorly:
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optic chiasma
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tuber cinereum
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Infundibulum
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mamillary body
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Anterior: lamina terminalis
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Posterior:
continues with midbrain
tegmentum
视上部位于视交叉上方，
由视上核和室旁核所组成；
结节部位于漏斗的后方；
乳头部位于乳头体。
Subthalamus
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Transition zone between diencephalons and tegmentum
of midbrain
Contain subthalamic nucleus, parts of red nucleus and
substantia nigra
内含底丘脑核，与黑质、红核、苍白球有密切联系，属锥体外系的
重要结构。人类一侧底丘脑核受损，可产生对侧肢体，尤其上肢较为显著的、不自主的舞蹈
样动作，成半身舞蹈病或半身颤搐(tarantism)。
Hypothalamus --connection

Supraoptic nucleus →supraoptic nucleus
(ADH) →supraopticohypophyseal tract
→posterior lobe of hypophysis
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Paraventricular nucleus → paraventicular
nucleus (oxytocin) →paraventriculohypophyseal
tract→posterior lobe of hypophysis
Hypothalamus
Function
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Regulates functions of neuroendocrine system
Autonomic nervous system
Third ventricle
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Position: a narrow ventricle
cleft lies within diencephalons
Boundaries
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Roof: choroids plexus
Floor: optic chiasma, tuber
cinereum, infundibulum and
mamillary body
Anterior: lamina terminalis
Posterior: continuous with
mesencephalic aqueduct
Lateral wall: dorsal thalamus and
hypothalamus
Communication
Third ventricle →mesencephalic aqueduct
→ fourth ventricle
The Telencephalon
External feature
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The telencephalon consists of
right and left cerebral hemisphere,
partially separated by cerebral
longitudinal fissure.
The cerebral transverse fissure
intervenes between the
hemispheres and the cerebellum
Each hemisphere has three
surfaces: superolateral, medial
and inferior
Three principal sulci
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Central sulcus
Lateral sulcus
Parietooccipital sulcus
Central sulcus
Parietooccipital sulcus
Lateral sulcus
Five lobes
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Frontal lobe
Parietal lobe
Temporal lobe
Occipital lobe
Insular lobe
Parietal lobe
Insular lobe
Hippocampus
Dentate gyrus
Hippocampal
formation
Functional location of
cerebral cortex
First somatic motor area
Position: located in precentral gyrus and anterior
portion of paracentral lobule
First somatic motor area
Characters
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Representation is inverted,
but head and face are
upright
A body part is represented
by a cortical area
proportional to its use
rather than its size
Receiving fibers from postcentral
gyrus, VA, VL and VPL, sending
out fibers to form pyramidal tract,
controlling voluntary movements
First somatic sensory area
Position－lies in
postcentral gyrus and
posterior portion of
paracentral lobule
First somatic sensory area
Characters
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Sensory representation,
like motor area, is
crossed and inverted
Receiving and interpret
sensation from opposite
side of body
Auditory area
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Located in transverse
temporal gyri
Receive auditory
information from both
ears
Visual area
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Lie on either side of
calcarine sulcus in medial
surface of occipital lobe
Visual cortex of one
hemisphere receives
impression from temporal
part of retina of same side
and nasal part of opposite
side
Lesions of visual cortex
produce contralateral
homonymous visual field
defections
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Vestibular area: located in front of superior temporal
gyrus
Olfactory area : located near the uncus
Taste area : located at frontal operculum
Language area
It is dominant in left hemisphere in
right-handed person
 Motor speech area
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Writing area
Located in posterior portion of
middle frontal gyrus
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Damage: agraphia
Auditory speech area
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Located in posterior portion of
inferior frontal gyrus
Damage: motor aphasia
Located in posterior portion of
superior temporal gyrus
Lesion: sensory aphasia
Visual speech area
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Located in angular gyrus
Lesion: alexia
Internal structures
Lateral ventricle
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Position:
located in cerebral hemispheres
Four parts
 Central part: lies in parietal lobe
 Anterior horn: extends into frontal lobe
 Posterior horn extend into occipital lobe
 Inferior horn: extend into temporal lobe
Communication
lateral ventricle → interventricular foramen → third ventricle
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Basal nuclei
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Corpus striatum
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Lentiform nucleus
Caudate nucleus
Claustrum
Amygdaloid body
Globus pallidus
putamen
－paleostriatum
Neostriatum
White matter
Association fibers
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Run between gyri within the
same hemisphere
Cerebral arcuate fibers
Superior
longitudinal fasciculi
Inferior
longitudinal fasciculi
Uncinate fasciculus
Cingulum
Commissural fibers
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－ run between left and
right hemisphere
Corpus callosum: rostrum,
genu, trunk, splenium
Anterior commissure
Fornix and commissure of
fornix
Projection fibers: connect
cortex with lower part of brain
and spinal cord and they
include both ascending and
descending fibers
Internal capsule
 Position: a thick lamina of
white matter lying between
caudate nucleus, thalamus
and lentiform nucleus
Three parts
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Anterior limb of internal capsule
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Genu of internal capsule
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Lies between caudate nucleus and
lentiform nucleus
Containing frontopontine tract and
anterior thalamic radiation
Is angle at which anterior and
posterior limbs meet
Containing corticonuclear tract
Posterior limb of internal capsule
Lies between thalamus and lentiform
nucleus

Contain corticospinal tract,
corticorubral tract, central
thalamic radiation, parietooccipito-temporo-pontine tract,
acoustic radiation and optic
radiation
Anterior thalamic radiation
Head of caudate nucleus
Frontopontine tract
Corticonuclear tract
Corticospinal tract
Dorsal thalamus
Central thalamic
radiation
Lentiform nucleus
Corticorubral tract
Parieto-occipitotemporo-pontine tract
Acoustic radiation
Medial geniculate body
Optic radiation
Lateral geniculate body
Limbic system
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Composition
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Limbic lobe: includes septal area, cingulated gyrus, parahippocampal
gyrus, hippocampus, dentate gyrus, temporal pole, anterior part of
insular lobe and so on
Associated subcortical nuclei: amygdaloid body, septal nuclei,
hypothalamus, epithalamus, anterior nucleus group of thalamus,
tegmentum of midbrain
Function: concerned with visceral activities, olfaction, emotion
and memory, so this system is called ‘visceral brain’