Lecture 11: Development, Plasticity and Recovery of Function

how is the central nervous system development mapped?

white matter is clustered in the middle and grows, becomes a lot more intricate by the 2nd year of life

how does myelin develop?

enormous amount of myelination occurs in the first year of life, dips out of the corpus collosum

how does cortical surface area develop?

plateaus out, brain stops getting bigger

what develops first in the brain

the brainstem

what does the brainstem (hindbrain) control?

breathing, heart rate, swallowing

does sensory or motor systems develop first?

motor systems, more important to survival

which develops first: interneurons or projection neurons?

projection neurons

what is the function of projection neurons?

connect between structures

what is the function of interneurons?

connect sensory and motor neurons and stay within one structure, make local connections

also called micro neurons

which happens first, axogenesis or dendrogenesis ?

axogenesis

why do baby neurons cross across the brain instead of going straight up to final destination?

they need to gain experience and communicate with other baby neurons

what did Roger Sperry study in retina cells to neuron mapping?

the chemoaffinity hypothesis, neurons make connections with target based on molecular markers

Greenough's experiments comparing rats raised in different conditions demonstrated that rats raised in impoverished environments:

Had impaired neuronal development relative to rats raised in enriched environments.

According to Roger Sperry's work and resulting hypothesis, the pathfinding activities of newly forming axons rely on:

chemical gradients

which forms first, the cerebral cortex or the medulla?

the medulla, the brain forms bottom-up

what is the function of neural darwinism?

cells that haven't made meaningful connections get destroyed

the most-used synaptic connections remaining and the least-used being removed

we only keep the most useful connections

which has more neurons, a zygote or an adult?

a zygotę