Neonatal and Postnatal Brain Development Flashcards
Primary neurolation
3-4 weeks of gestation
*Formation of notocord, neural tube, neural crest
Myeloschisis
Newborn has a missing roofplate, vertebral arch, and skin covering it
-Will see opening on child’s back
Secondary Neurolation
Canalization: 4-7wks
Retrogressive Determination 7wks-Birth
Diastematomyelia
Defects in the vertebrae formation lead to formation of fat in the way
Myelocystocele
Formation of cyst at the site of neural crest fusion
=>infxns
Aprosencephaly
Absence of telencephalon and diencephalon
Atelencephaly
Absence of telencephalon
Neuronal proliferation
Formed by symmetrical divisions of stem cells in the ventricular and subventricular zones
Microcephaly/Microlissencephaly
Reduced proliferation of glia in germinal zone
Inside-out neuronal migration
Cells destined for deepest cortical layer migrate 1st
*Formation of cortical preplate occurs; by Week 24, baby has full complement of neurons
3 Mechanisms of neuronal migration
Locomotion guided-Neurons move along scaffolding of glial fibers
Somal translocation- Cell body pulls towards pial surface by shortening its radial process
Tangential migration- GABAergic neurons move parallel to germinal zone
Pachygyria
Presence of few broad, flat gyri w/ a thickened cortex
Schizencephaly
Disorder of neuronal migration leading to abnormal cortical migration
- Commonly has clefts in brain
- affects mostly women
Subcortical band heterotopia
Deep bands of gray matter that can be found in subcortex right beside ventricles
-Developmental abnormalities
Progression of myelination
Proximal before distal
- Central before lateral
- Posterior before anterior
- Brainstem and thalamus are myelinated @ birth
Stress on developing brain
Positive- Small amnt; helps child learn self assurance
Tolerable- Long periods of stress w/ increased amnts of cortisol; usually reversible
Negative- Irreversible damage caused by chronic abuse; can lead to disease susceptibility as an adult
Nicotine effects on neonatal brain
Decreases Ach utility
Synaptic pruning
Repeated neuronal activity during critical growth periods stabilizes circuits and they will no longer need less energy (glucose)
Myelinated Areas @ Birth
Dorsal brainstem, optic tract, thalamus
Nicotine on Neonatal Brain
Decreased Ach fnxn
Microlissencephaly
Extremely small head w/ thickened cortex
Most at risk kids
Rejected kids
When to start treating for depression
When grief lasts longer than 2 months
-Educate patient that thoughts may not go away but overall mood will be better
