Brain growth

Question 1

What are some of the main features of brain growth in animals?

Answer 1

important aspect in postnatal development is growth & maturation of specific cells in the body -> functioning organs. Brain cells follow same principles and major features for brain growth are:

• NEURAL CELL CONNECTIVITY (SYNAPTIC DENSITY)
• PROLIFERATION & MIGRATION OF NEURONS & GLIAL CELLS
• MYELINATION OF NERVE FIBRES

Question 2

Describe Postnatal Proliferation and Migration of neurons…

Answer 2

NEURONS
- Neurogenesis continues to only a very limited
degree
- Subventricular zone, new neurons continue to emerge and migrate to the olfactory bulb
- Neurons are also produced in the dentate gyrus of the hippocampus, where they migrate from the subgranular layer to the nearby granular layer
- Neurogenesis appear to continue throughout adult life but produce only a small percentage of the neuronal population

Question 3

Describe Postnatal Proliferation and Migration of glial cells…

Answer 3

GLIAL CELLS
Proliferation and migration of glial precursors and differentiation of astrocytes and oligodendrocytes are largely postnatal processes and maturation of these cells continue throughout childhood

Question 4

Describe the process of myelination…

Answer 4

DEFINITION: The acquisition, development, or formation of a myelin sheath around a nerve fibre enables nerve cells to transmit information faster and allows for more complex brain processes
MORE INFO:
- Large groups of myelinated axons, which connect various regions in the brain, appear visibly as “white matter”
- in humans, occurs between 180days gestation (-30 months) until 17 years old

Question 5

What is synaptic pruning?

Answer 5

Naturally occurring cell death, which involves the normal loss of the neurons within a brain -> facilitate changes in neural structure by reducing the overall number of neurons and synapses, leaving more efficient synaptic configurations that is general feature of mammalian neurological development

• These processes reflect nonpathological events that play an essential role in establishing the complex networks of the developing brain
• starts near conception -> sexual maturation (humans)