Brain development - Neural proliferation
6 important questions on Brain development - Neural proliferation
Nearly all neurons are produced prenatally, except for
- Dentate gyrus of the hippocampus
- olfactory bulb
Passive cell displacement
- Older cells are pushed up by recently born cells
- outside-in pattern = more mature cells in outer layers and younger cells are inside (e.g. Thalamus, hippocampus)
Active cell migration
- Young cells moving past previously pattern generated cells
- inside-out pattern = more mature layers are inside whilst younger outside (e.g. Laminar structure of the cerebral cortex)
- Higher grades + faster learning
- Never study anything twice
- 100% sure, 100% understanding
Most adults have similar functions within approximately the same areas of the cortex, but how is it possible?
2 hypothesis
- Protomap hypothesis
- Protocortex hypothesis
Theory:
despite primary sensory regions being the best candidates for genetic pre-specification, these regions can have their properties significantly changed through experience.
Conclusion:
Current reviews of the evidence converge on views that are midway between the protomap and protcortex hypotheses:
- Graded patterns of gene expression create large-scale regions with combinations of properties that may better suit certain computations (similar to a very coarse protomap)
- it is within these large-scale regions that smaller scale functional areas arise through the activity-dependent mechanisms associated with the protocortex view
The question on the page originate from the summary of the following study material:
- A unique study and practice tool
- Never study anything twice again
- Get the grades you hope for
- 100% sure, 100% understanding
![Trustpilot Logo](/images/design_2020/lp/clp-trustpilot-en.png)