The Telencephalon

山东大学医学院解剖教研室李振华

External feature The telencephalon consists of righ

t 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 Central sulcus 中央沟 Lateral sulcus 外侧沟 Parietooccipital sulcus 顶枕沟

Central sulcus

Lateral sulcus

Parietooccipital sulcus

Five lobes Frontal lobe 额叶 Parietal lobe 顶叶 Temporal lobe 颞叶 Occipital lobe 枕叶 Insular lobe 岛叶

Frontal lobe

Parietal lobe

Occipital lobe

Temporal lobe

Insular lobe

Sulci and gyri of Superolateral surface

Frontal lobe: Precentral sulcus 中央前沟 Superior frontal sulcus 额上沟 Inferior frontal sulcus 额下沟 Precentral gyrus 中央前回 Superior frontal gyrus 额上回 Middle frontal gyrus 额中回 Inferior frontal gyrus 额下回

Sulci and gyri of Superolateral surface

Precentral sulcus Precentral gyrus

Superior frontal sulcus

Inferior frontal sulcus

Superior,middleand inferioe frontal gyri

Parietal lobe: Postcentral sulcus 中央后沟 Postcentral gyrus 中央后回 Intraparietal sulcus 顶内沟 Superior parietal lobule 顶上小叶 Inferior parietal lobule 顶下小叶 Supramarginal gyrus 缘上回 Angular gyrus 角回

Sulci and gyri of Superolateral surface

Postcentral sulcus

Postcentral gyrus

Superior parietal lobule

Supramarginal gyrus

Angular gyrus

Intraparietal sulcus

Temporal lobe: Superior temporal sulcus 颞上沟 Inferior temporal sulcus 颞下沟 Superior temporal gyrus 颞上回 Middle temporal gyrus 颞中回 Inferior temporal gyrus 颞下回 Transverse temporal gyri 颞横回

Sulci and gyri of Superolateral surface

Superior temporal sulcus

Inferior temporal sulcus Superior temporal gyrus

Middle temporal gyrus

Inferior temporal gyrus

Transverse temporal gyri

Sulci and gyri of Superolateral surface

Precentral sulcus

Precentral gyrus

Superior frontal sulcus

Inferior frontal sulcus

Superior,middleand inferioe frontal gyri

Postcentral sulcus

Postcentral gyrus

Superior parietal lobule

Supramarginal gyrus

Angular gyrus

Superior temporal sulcus

Inferior temporal sulcus Superior temporal gyrus

Middle temporal gyrus

Inferior temporal gyrus

Sulci and gyri of medial surface Corpus callosum 胼胝体

Callosal sulcus 胼胝体沟 Cingulate gyrus 扣带沟 Cingulate sulcus 扣带回 Marginal ramus 缘支 Paracentral lobule 中央旁小叶 Calcarine sulcus 距状沟 Cuneus 楔叶 Lingual gyrus 舌回

Sulci and gyri of medial surface

Corpus callosum

Callosal sulcus

cingulate gyrus

Cingulate sulcus

Marginal ramus

Paracentral lobule

Calcarine sulcus

Cuneus

Parietooccipital sulcus

Lingual gyrus

Sulci and gyri of inferior surface Olfactory bulb 嗅球

Olfactory tract 嗅束 Olfactory trigone 嗅三角 Anterior perforated substance 前穿质 Collateral sulcus 侧副沟 Occipitotemporal sulcus 枕颞沟 Medial occipitotemporal gyrus 枕颞内侧回 Lateral occipitotemporal gyrus 枕颞外侧

回 Hippocampal sulcus 海马沟 Parahippocampal gyrus 海马旁回 Uncus 钩 Hippocampus 海马 Dentate gyrus 齿状回

Hippocampal formation 海马结构

Inferior surface

Olfactory bulb

Olfactory tract

Olfactory trigone

Anterior perforated substance

Collateral sulcus

Occipitotemporal sulcus

Medial and lateraloccipitotemporal gyri

Parahippocampal gyrus

Uncus

Hippocampus

Dentate gyrus

Hippocampal formation

Histology of the cerebral cortex Archicortex 原皮质

(hippocampal formation 海马结构 )

Paleocortex 古皮质 (rhinencephalon 嗅脑 )

Neocortex 新皮质 (most of cerebral cortex)

3 cell layers

6 cell layers

Functional location of cerebral cortex

First somatic motor area 第一躯体运动区Position: located in precentral gyrus and anterior port

ion of paracentral lobule

First somatic motor area 第一躯体运动区Characters

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 第一躯体感觉区

Position － lies in postcentral gyrus and posterior portion of paracentral lobule

First somatic sensory area 第一躯体感觉区

Characters Sensory representation,

like motor area, is crossed and inverted

Receiving and interpret sensation from opposite side of body

Auditory area 听区

Located in transverse temporal gyri

Receive auditory information from both ears

Visual area 视区 Lie on either side of calcarin

e 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

Vestibular area 平衡觉区 : located in front of superior temporal gyrus

Olfactory area 嗅觉区 : located near the uncus Taste area 味觉区 : located at frontal operculum

Language area 语言中枢It is dominant in left hemisphere in rig

ht-handed person Motor speech area 运动性语言中

枢 Located in posterior portion of inferi

or frontal gyrus Damage: motor aphasia

Writing area 书写中枢 Located in posterior portion of midd

le frontal gyrus Damage: agraphia

Auditory speech area 听觉性语言中枢 Located in posterior portion of supe

rior temporal gyrus Lesion: sensory aphasia

Visual speech area 视觉性语言中枢 Located in angular gyrus Lesion: alexia

Lateral ventricle 侧脑室 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

Internal structures

Communicationlateral ventricle → interventricular foramen → third ventricle

Basal nuclei 基底核 Corpus striatum

纹状体 Lentiform nucleus

豆状核 Caudate nucleus

尾状核 Claustrum 屏状核 Amygdaloid body 杏仁体

Globus pallidus 苍白球

putamen 壳 Neostriatum 新纹状体

－ paleostriatum 旧纹状体

White matterAssociation fibers

联络纤维 Run between gyri within the

same hemisphere Cerebral arcuate fibers

大脑弓状纤维 Superior

longitudinal fasciculi 上纵束

Inferior longitudinal fasciculi 下纵束

Uncinate fasciculus 钩束 Cingulum 扣带

Commissural fibers 连合纤维 － run between left and right hemisphere

Corpus callosum 胼胝体 : rostrum, genu, trunk, splenium

Anterior commissure 前连合 Fornix and commissure of f

ornix 穹隆和穹隆连合

Projection fibers 投射纤维 : 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 w

hite matter lying between caudate nucleus, thalamus and lentiform nucleus

Three parts Anterior limb of internal capsule

内囊前肢 Lies between caudate nucleus and le

ntiform nucleus Containing frontopontine tract and an

terior thalamic radiation Genu of internal capsule 内囊膝

Is angle at which anterior and posterior limbs meet

Containing corticonuclear tract Posterior limb of internal capsule

内囊后肢 Lies between thalamus and lentiform n

ucleus Contain corticospinal tract, cortico

rubral tract, central thalamic radiation, parieto-occipito-temporo-pontine tract, acoustic radiation and optic radiation

Anterior thalamic radiation

Frontopontine tract

Lentiform nucleus

Corticorubral tract

Parieto-occipito-temporo-pontine tract

Acoustic radiation

Optic radiation

Head of caudate nucleus

Corticonuclear tract

Corticospinal tract

Dorsal thalamus

Central thalamic radiation

Medial geniculate body

Lateral geniculate body

Limbic system 边缘系统 Composition

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’