Neurology ch.3. Development of the Nervous System

anencephaly

Neurological development ceases at the brain stem leaving child without cerebral hemispheres and higher cortical functions. Type of NTD

dorsal induction

3-7 weeks (GA) period when neural plate is formed by fourth week neurulation will occur to make the neural tube

ectoderm

Turns into the skin and nervous system

enceohalocele

Malformation of the skull where part of the brain protrudes from the skull (types of NTD)

holoprosencephaly

Failure in brain cleavage

hypomyelination

Underproduction of myelin

lissencephaly

Caused by lack of reelin abnormally smooth brain. Lack of wrinkles

microcephaly

Abnormally small brain mass

neural plate

Dorsal ectoderm thickens around the third week of development to form this

neural tube

Neurulation forms this

neural tube defects (NTDs)

Failure of the neural pores to close properly

neurogenesis

Birth of new neurons

neuropores

Ends of the neural tube close around 6 weeks GA

neurulation

When the neural plate becomes the neural tube

polymicrogyria

Too may folds in the cerebral hemispheres

rhombencephalon

Becomes the myelencephelon or medulla

schizencephaly

Abnormal openings of cleft in the cerebral hemispheres

spina bifida

Spinal cord and fluid and the meninges protrude from the spine

synaptic pruning

Connections in the brain that aren’t being used are eliminated

synaptogenesis

When neurons form synapses and dendrites

telencephalon

Becomes the cerebral hemispheres. Cerebral cortex basal ganglia and olfactory bulbs

ventral induction

Face and brain development from superior end of neural tube. 2-3 months GA