Post on 27-May-2020
transcript
Systems Neuroscience 2020
Brain Anatomy Overview
and
Ascending and Descending Pathways
Daniel J. Felleman, Ph.D.
Professor
Dept. of Neurobiology and Anatomy
MSB 7.168
713-500-5629
Daniel.felleman@uth.tmc.edu
Objectives
• Organization of the nervous system: central vs. peripheral, autonomics, axes
• Spinal cord
• Meninges
• Overview: organization of cortex: functional divisions of lobes
• Architectonics
• Blood supply
• Brain stem and cranial nerves
• Diencephalon: thalamic and hypothalamic nuclei
• Gustatory/Olfactory systems: ascending pathways and cortical targets
• Visual system: eye and primary retinal pathways
• Vestibular system: ascending pathways and cortical targets
• Auditory system: ascending pathways and cortical targets
• Somatosensory system: ascending pathways and cortical targets
• Motor system(s): descending pathways and cortical/subcortical origins
• Limbic system: organization and basic pathways
Figure A1 (A) Anatomical terminology of the brain and brainstem; (B) Major planes of section
Axis Conventions in Human Neuroanatomy
Figure A2 The subdivisions and components of the central nervous system
Spinal Cord Gross Anatomy and Meninges
Figure A4 Relationship of the spinal cord and spinal nerves to the vertebral column
Figure A5 Internal structure of the spinal cord
Figure A6 The internal histology of the human spinal cord in a lumbar segment
Meninges, Dural Sinuses and CSF Circulation
CSF
Meninges, superficial veins, diploic vessels and arachnoid granulations
Dural sinuses
Primary and Secondary Vesicles: Early Neuroembryology
Embryological derivation of internal structure in the brainstem (Part 1)
Surface anatomy of the cerebral hemisphere
Lateral view of the human brain
Figure A11 Views of the human brain
Figure A12 Midsagittal view of the human brain
Frontal lobe major sulci and gyri
Organization of Cerebral Cortex: Lobes and Gyri V
Organization of Cerebral Cortex: Lobes and Gyri IV
Frontal lobe major sulci and gyri
Organization of Cerebral Cortex: Lobes and Gyri IIIParietal lobe major sulci and gyri
Organization of Cerebral Cortex: Lobes and Gyri II
Temporal lobe major sulci and gyri
Visual System: Occipital Lobe
4 Targets of Retinal Ganglion Cells: Ascending Visual Pathway
• Lateral Geniculate Nucleus (visual perception)
• Superior Colliculus of Midbrain (control of eye movement)
• Pretectum of midbrain (control of pupillary light reflex)
• Suprachiasmatic nucleus of the hypothalamus (control of diurnal rhythm)
Nasal retina
Temporalretina
Optic nerve (CN II)
Optic chiasm
(fibers from nasal retina
cross)
Optic tract
Temporal visual field
Visual field and visual pathways
contralateral visual fieldcontralateral visual field
Visual field and visual pathways
Lateral geniculate nucleus
(thalamus)
Visual fields
Left eye Right eye
Optic radiation
Meyer’s loop= upper visual field
LG
Lateral ventricle
Calcarine sulcus
Primaryvisual cortex
(area 17)
Optic radiation (geniculo-calcarine tract)
Map of Right Visual Field
Nasal
TemporalTemporal
Visual cortex
Blindness of i.l. eye (1)
Bitemporalhemianopia (2)
c.l. homonymoushemianopia (3)
c.l. homonymoussuperior/upper quadrant-anopia (4)
c.l. homonymousupper (6)lower (5)quadrant-anopiawith macula sparing
Consensual (right eye)✓
III (Preganglionic parasympathetic fibers)
Ciliary ganglion
Pupillary light reflex
Ciliary nerve
II (R)- lesion
III (R) -
lesion
LG
SCEdinger-Westphal nucleus
(“parasympathetic” subnucleus of III)
brachiumSC
post. comm.
Iris sphinctermuscle
Consensual (right eye)
Direct(right eye)
LGBrSC
II
Direct(right eye)
II
Right Left
anisocoria
Pretectal area
Near (accommodation) reflex
• Convergence of the two eyesMedial rectus muscle (both eyes) = III (oculomotor nerve)
• Near accommodation: lens thickensCiliary muscle = circular muscle = III (parasympathetics from
Edinger Westphal nucleus)
→ Relaxation of zonular fibers
• Pupillary constriction to increase depth of focus
Iris sphincter muscle = III (parasympathetics from Edinger Westphal nucleus)
Requires participation of the visual cortex
Lens
Zonules(zonular fibers)
Ciliary
body
Contraction of ciliary muscle(= circular muscle)
➢Relaxation of zonular fibers
➢Lens thickens
Regulation of lens thickness
Sphincter
(circular)
Dilator
(radial)Ciliarymuscle
Cornea
Regulation of pupil size: iris muscles
sympatheticspara-symp
Pupil size regulation
Medial Wall and Corpus Callosum
Human Head MRI
Figure A14 Internal structures of the brain seen in coronal section
Organization of Cerebral Cortex: Architectonics
circa 1900
The Human Connectome: Multi-modal Parcellation of Human Cortex190+ multi-modally defined areas vs. Brodmann (44) and other architectonic
maps
Partially inflated cortical surface to aid the visualization of cortex within sulci
Full unfolded, 2D cortical maps
Human Connectome Project
190 areas on partially inflated cortical hemisphere- Left
Unfolded Cortical Hemisphere- Left
Arterial Supply including the Circle of Willis
Cerebral artery
distribution
Figure A16 The major arteries of the brain
Figure A17 Blood supply of the three subdivisions of the brainstem
Cranial Nerves and Nuclei in Brainstem
Figure A7 The locations of the cranial nerves as they enter or exit the midbrain, pons, and medulla
TABLE A3 Classification and Location of the Cranial Nerve Nucleia
Brainstem Cranial Nerves: Components,
Functions, and Cross-sections
Brainstem Cranial Nerves: Components,
Functions, and Cross-sections
Figure A8 Brainstem cranial nerve nuclei locations that are the target or source of cranial nerves
Cranial Nerve Nuclei
Figure A9 Internal organization along the rostral–caudal axis
Diencephalon: Thalamic and Hypothalamic Nuclei
BOX A Thalamus and Thalamocortical Relations (Part 1)
Olfactory and Gustatory Pathways
4 Targets of Retinal Ganglion Cells: Ascending Visual Pathway
• Lateral Geniculate Nucleus (visual perception)
• Superior Colliculus of Midbrain (control of eye movement)
• Pretectum of midbrain (control of pupillary light reflex)
• Suprachiasmatic nucleus of the hypothalamus (control of diurnal rhythm)
Nasal retina
Temporalretina
Optic nerve (CN II)
Optic chiasm
(fibers from nasal retina
cross)
Optic tract
Temporal visual field
Visual field and visual pathways
contralateral visual fieldcontralateral visual field
Visual field and visual pathways
Lateral geniculate nucleus
(thalamus)
Visual fields
Left eye Right eye
Optic radiation
Meyer’s loop= upper visual field
LG
Lateral ventricle
Calcarine sulcus
Primaryvisual cortex
(area 17)
Optic radiation (geniculo-calcarine tract)
Map of Right Visual Field
Nasal
TemporalTemporal
Visual cortex
Blindness of i.l. eye (1)
Bitemporalhemianopia (2)
c.l. homonymoushemianopia (3)
c.l. homonymoussuperior/upper quadrant-anopia (4)
c.l. homonymousupper (6)lower (5)quadrant-anopiawith macula sparing
Consensual (right eye)✓
III (Preganglionic parasympathetic fibers)
Ciliary ganglion
Pupillary light reflex
Ciliary nerve
II (R)- lesion
III (R) -
lesion
LG
SCEdinger-Westphal nucleus
(“parasympathetic” subnucleus of III)
brachiumSC
post. comm.
Iris sphinctermuscle
Consensual (right eye)
Direct(right eye)
LGBrSC
II
Direct(right eye)
II
Right Left
anisocoria
Pretectal area
Lens
Zonules(zonular fibers)
Ciliary
body
Contraction of ciliary muscle(= circular muscle)
➢Relaxation of zonular fibers
➢Lens thickens
Regulation of lens thickness
Sphincter
(circular)
Dilator
(radial)Ciliarymuscle
Cornea
Regulation of pupil size: iris muscles
sympatheticspara-symp
Pupil size regulation
Visual System II: Optic Nerve Afferents and Efferents
Vestibular Ascending and Descending Pathways
Auditory Ascending Pathway
Somatosensory Pathways
Somatosensory Pathways II
Motor System I: Cortico-spinal
Motor System II: vestibulo-spinal and rubro-spinal pathways
Motor System III: reticulo-spinal pathways
Limbic System I
Limbic System II
Plate 1 Surface features of a human brain specimen (Part 1)
Plate 1 Surface features of a human brain specimen (Part 2)
Plate 1 Surface features of a human brain specimen (Part 3)
Plate 1 Surface features of a human brain specimen (Part 4)
Plate 2 Coronal section demonstrating internal forebrain structures, MRI (Part 1)
Plate 2 Coronal section demonstrating internal forebrain structures, MRI (Part 2)
Plate 2 Coronal section demonstrating internal forebrain structures, MRI (Part 3)
Plate 2 Coronal section demonstrating internal forebrain structures, MRI (Part 4)
Plate 3 Axial section demonstrating internal forebrain structures, T1-weighted MRI (Part 1)
Plate 3 Axial section demonstrating internal forebrain structures, T1-weighted MRI (Part 2)
Plate 3 Axial section demonstrating internal forebrain structures, T1-weighted MRI (Part 3)
Plate 3 Axial section demonstrating internal forebrain structures, T1-weighted MRI (Part 4)
Plate 3 Axial section demonstrating internal forebrain structures, T1-weighted MRI (Part 5)
Plate 3 Axial section demonstrating internal forebrain structures, T1-weighted MRI (Part 6)
Plate 3 Axial section demonstrating internal forebrain structures, T1-weighted MRI (Part 7)
Plate 3 Axial section demonstrating internal forebrain structures, T1-weighted MRI (Part 8)
Plate 4 Sagittal section demonstrating internal forebrain structures, T1-weighted MRI (Part 1)
Plate 4 Sagittal section demonstrating internal forebrain structures, T1-weighted MRI (Part 2)
Plate 4 Sagittal section demonstrating internal forebrain structures, T1-weighted MRI (Part 3)
Plate 4 Sagittal section demonstrating internal forebrain structures, T1-weighted MRI (Part 4)
Plate 5 Transverse section acquired and prepared to simulate myelin staining (Part 1)
Plate 5 Transverse section acquired and prepared to simulate myelin staining (Part 2)
Plate 5 Transverse section acquired and prepared to simulate myelin staining (Part 3)
Plate 5 Transverse section acquired and prepared to simulate myelin staining (Part 4)
Plate 6 Transverse section acquired and prepared to simulate myelin staining (Part 1)
Plate 6 Transverse section acquired and prepared to simulate myelin staining (Part 2)
Plate 6 Transverse section acquired and prepared to simulate myelin staining (Part 3)
Plate 6 Transverse section acquired and prepared to simulate myelin staining (Part 4)
PLATE 6 (1) Brainstem Atlas
PLATE 6 (2) Brainstem Atlas
PLATE 6 (3) Brainstem Atlas
PLATE 6 (4) Brainstem Atlas
PLATE 7 (1) Spinal Cord Atlas
PLATE 7 (2) Spinal Cord Atlas
PLATE 7 (3) Spinal Cord Atlas
PLATE 7 (4) Spinal Cord Atlas