Summary
Birth of new neurons in adult brain regions such as the hippocampal dentate gyrus.
In depth
Adult neurogenesis occurs in the subgranular zone of the dentate gyrus and subventricular zone in rodents; evidence in adult humans is debated. Exercise and enrichment increase it, while stress decreases it.
Adult-born neurons may contribute to pattern separation. Antidepressants and exercise may increase it. Evidence in adult humans remains disputed.
Example: stress reduces hippocampal neurogenesis in rodents.
In rodents, new neurons in the dentate gyrus support pattern separation and are boosted by exercise and enriched environments, and reduced by stress. Joseph Altman found evidence in the 1960s, and Fernando Nottebohm showed it in songbirds that learn new songs. In humans, evidence is mixed: carbon-14 dating studies (Frisen) indicate about 700 new hippocampal neurons per day, whereas other studies (Sorrells et al., 2018) found little after childhood, a debate partly resolved by newer single-nucleus analyses supporting some neurogenesis. The subventricular zone's contribution to olfactory neurons is mainly in rodents.
Therapeutic interest: stimulating neurogenesis for depression (antidepressants may need it in rodents), stroke, and Alzheimer disease, as well as transplantation of stem cell-derived neurons for Parkinson disease. Reprogramming glia into neurons is under study.
Frequently asked questions
What is Neurogenesis?
Birth of new neurons in adult brain regions such as the hippocampal dentate gyrus.
Which area of biology covers Neurogenesis, and how advanced is it?
Neurogenesis is one of the 54 topics in Neuroscience. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Neuroinflammation, Hippocampus and Memory Consolidation, Neural Development.
Why does Neurogenesis matter?
If adults can replace neurons, brain repair might be possible.
Can you give an example of Neurogenesis?
Songbirds add neurons seasonally to learn new songs.
What should I learn before Neurogenesis?
Work through the Beginner topics in Neuroscience first, such as Nervous System, Neuron, Central and Peripheral Nervous Systems, then return to Neurogenesis. Advanced topics assume the Intermediate vocabulary.
What topics are related to Neurogenesis?
The closest topics to Neurogenesis are Neuroinflammation, Hippocampus and Memory Consolidation, Neural Development, Limbic System. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Neurogenesis?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Neurogenesis. To practise the whole of Neuroscience, use the Neuroscience quiz.
How is Neurogenesis different from Neuroinflammation?
Neurogenesis: Birth of new neurons in adult brain regions such as the hippocampal dentate gyrus. Neuroinflammation: Activated microglia and astrocytes release cytokines that contribute to neurological disease. Read both side by side and note what each one explains.
How should I study Neurogenesis step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Neuroinflammation and explain the difference aloud. Finally, take the Neuroscience quiz and come back to this page for any question you miss.