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[[Media:File:2011 Lecture - Neural Development.pdf}Lecture Slides PDF]]
[[Media:2011 Lecture - Neural Development.pdf}Lecture Slides PDF]]





Revision as of 21:54, 3 October 2011

Introduction

Cerebrum development human embryo (week 8, Stage 22)

This will be a guest lecturer Prof. Ken Ashwell, who will provide his own notes. The information below is provided only as background.


[[Media:2011 Lecture - Neural Development.pdf}Lecture Slides PDF]]


Neural Links: ectoderm | neural | neural crest | ventricular | sensory | Stage 22 | gliogenesis | neural fetal | Medicine Lecture - Neural | Lecture - Ectoderm | Lecture - Neural Crest | Lab - Early Neural | neural abnormalities | folic acid | iodine deficiency | Fetal Alcohol Syndrome | neural postnatal | neural examination | Histology | Historic Neural | Category:Neural
Neural Parts: neural | prosencephalon | telencephalon cerebrum | amygdala | hippocampus | basal ganglia | diencephalon | epithalamus | thalamus | hypothalamus‎ | pituitary | pineal | mesencephalon | tectum | rhombencephalon | metencephalon | pons | cerebellum | myelencephalon | medulla oblongata | spinal cord | neural vascular | ventricular | lateral ventricles | third ventricle | cerebral aqueduct | fourth ventricle | central canal | meninges | Category:Ventricular System | Category:Neural

Early Brain Structure

Primary Vesicles

CNS primary vesicles.jpg

  • rostral neural tube forms 3 primary brain vesicles (week 4)
  • 3 primary vesicles: prosencephalon (forebrain), mesencephalon (midbrain), rhombencephalon (hindbrain)

Secondary Vesicles

CNS secondary vesicles.jpg

From the 3 primary vesicles developing to form 5 secondary vesicles

  • prosencephalon- telencephalon (endbrain, forms cerebral hemispheres), diencephalon (betweenbrain, forms optic outgrowth)
  • mesencephalon
  • rhombencephalon- metencephalon (behindbrain), myelencephalon (medullabrain)

Neural Layers

Brain

Stage 22 image 150.jpg Stage 22 image 151.jpg
Human Embryo developing head cross section (Week 8, Stage 22) Detail of developing cortex (shown in blue box)

Spinal Cord

Stage 13 image 057.jpg Stage 22 image 176.jpg
Stage 13 Stage 22

Fetal Neural

Neural-development.jpg

Timeline of events in Human Neural Development

Brain ventricles and ganglia development 03.jpg

Brain fissure development 02.jpg

Gray0654.jpg Gray0655.jpg Gray0658.jpg
Human brain at three months (median sagittal section) Human brain at four months (inferior surface) Human brain at five months (outer surface)

During the fetal period there is ongoing growth in size, weight and surface area of the brain and spinal cord. Microscopically there is ongoing: cell migration, extension of processes, cell death and glial cell development.

Cortical maturation (sulcation and gyration) and vascularization of the lateral surface of the brain starts with the insular cortex (insula, insulary cortex or insular lobe) region during the fetal period. This cerebral cortex region in the adult brain lies deep within the lateral sulcus between the temporal lobe and the parietal lobe.

  • sulcation - The process of brain growth in the second to third trimester which forms sulci, grooves or folds visible on fetal brain surface as gyri grow (gyration). Abnormalities of these processes can lead to a smooth brain (lissencephaly).
  • gyration - The development of surface folds on the brain (singular, gyrus)

Insular Gyral and Sulcal Development

  • 13-17 gestational weeks - appearance of the first sulcus
  • 18-19 gestational weeks - development of the periinsular sulci
  • 20-22 gestational weeks - central sulci and opercularization of the insula
  • 24-26 gestational weeks - covering of the posterior insula
  • 27-28 gestational weeks - closure of the laeteral sulcus (Sylvian fissure or lateral fissure)

(Data from[1])

  • Between 29-41 weeks volumes of: total brain, cerebral gray matter, unmyelinated white matter, myelinated, and cerebrospinal fluid (from MRI)
    • grey matter- mainly neuronal cell bodies; white matter- mainly neural processes and glia.
  • total brain tissue volume increased linearly over this period at a rate of 22 ml/week.
  • Total grey matter also showed a linear increase in relative intracranial volume of approximately 1.4% or 15 ml/week.
  • The rapid increase in total grey matter is mainly due to a fourfold increase in cortical grey matter.
  • Quantification of extracerebral and intraventricular CSF was found to change only minimally.

(Text - modified from [2])


Neural development will continue after birth with substantial glial development, growth, death and reorganization occuring during the postnatally.


Links: Neural System - Fetal | Neuroscience - Regional specification of the developing brain

Thyroid System and Neural Development

Human thyroid system and neural development.jpg

Timeline of human thyroid system and brain development from conception to birth.[3] (Estimation of neurogenesis adapted from Bayer et al.[4])

Links: Endocrine - Thyroid Development


References

  1. <pubmed>17962979</pubmed>
  2. <pubmed>9485064</pubmed>
  3. <pubmed>12060827</pubmed>
  4. <pubmed>8361683</pubmed>

Movies

Computed Tomography

Mouse CT E11.5 movie-icon.jpg Adult human brain movie icon.jpg
Mouse E11.5 microCT scan Human Adult Brain


Magnetic Resonance Imaging

Human Embryo
Brain fissure development 03.jpg
Neural Sylvian Fissure

Historic Embryology

Images

Bailey, F.R. and Miller, A.M. (1921). Text-Book of Embryology. New York: William Wood and Co.

The nervous system

Gray, Henry. Anatomy of the Human Body. Philadelphia: Lea & Febiger, 1918.

Co-ordinator Note

Mhicon08.jpg

Dr Mark Hill

ANAT2341 Embryology S2 2011
--Mark Hill 06:47, 20 July 2011 (EST)

Course Content 2011

2011 Timetable: | Embryology Introduction | Fertilization | Cell Division/Fertilization | Week 1 and 2 Development | Week 3 Development | Week 1 to 3 | Mesoderm Development | Ectoderm, Early Neural, Neural Crest | Trilaminar Embryo to Early Embryo | Early Vascular Development | Placenta | Vascular and Placenta | Endoderm, Early Gastrointestinal | Respiratory Development | Endoderm and Respiratory | Head Development | Neural Crest Development | Head and Neural Crest | Musculoskeletal Development | Limb Development | Musculoskeletal | Renal Development | Genital | Kidney and Genital | Sensory | Stem Cells | Stem Cells | Endocrine Development | Endocrine | Heart | Integumentary Development | Heart and Integumentary | Fetal | Birth and Revision | Fetal

Glossary Links

Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers | Symbols | Term Link

Cite this page: Hill, M.A. (2024, March 28) Embryology Lecture - Neural Development. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Lecture_-_Neural_Development

What Links Here?
© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G