Neurons primarily grow in two main areas of the adult brain: the subventricular zone (SVZ) of the lateral ventricles and the subgranular zone (SGZ) of the hippocampal dentate gyrus. These regions are centers of neurogenesis, the process by which new neurons are formed.
Key Areas of Neurogenesis
Here's a breakdown of the two primary locations:
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Subventricular Zone (SVZ): Located along the lateral ventricles, the SVZ is a highly active area of neurogenesis. New neurons born here often migrate to the olfactory bulb, where they differentiate into specific types of interneurons.
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Subgranular Zone (SGZ): Found in the dentate gyrus of the hippocampus, the SGZ is another significant site of neurogenesis. Neurons generated in the SGZ become granule cells, which play a crucial role in learning and memory.
Significance of Neurogenesis
Neurogenesis is vital for:
- Brain plasticity: The ability of the brain to adapt and change over time.
- Learning and memory: Especially in the hippocampus, where new neurons contribute to the formation of memories.
- Olfactory function: In the olfactory bulb, new neurons contribute to the sense of smell.
Other Potential Areas
While the SVZ and SGZ are the best-established sites of neurogenesis, research suggests that it might also occur, to a lesser extent, in other brain regions. However, the evidence for neurogenesis outside these two areas is still debated.
In summary, while neuronal growth and development occur extensively during embryonic and early postnatal development throughout the brain, in the adult brain, new neuron generation is primarily concentrated in the subventricular zone of the lateral ventricles and the subgranular zone of the hippocampal dentate gyrus.
