Neurogenesis is a term that is used to refer to the birth of neurons in the brain. Neurons are the basic building blocks of the human brain. There are more than 100 billion of these cells in human brain. Each neuron has two or more protrusions called dendrites and axons. It receives inputs and produces outputs signals to enable us to live and interact with our surroundings. It was first established in the 1960s following work done by Dr Pasko Rakic of Yale University. Further research done over the years especially the last decade has shown that neurogenesis occurs throughout adult life.
The study of neurogenesis is important to find improved treatments for mental disorders such as Alzheimer, Huntington, epilepsy and traumatic brain injury.Researches have found that neurogenesis occurs in the hippocampus, an area that is associated with learning and memory, and the olfactory bulb, which is the area responsible for the sense of smell. Research shows that thousands of neurons are produced each day but most of these new cells die within weeks. In order for the neurons to survive it needs support from neighbouring glial cells, nutrients and also connection to other neurons.
Though there are many questions that unanswered about what actually triggers neurogenesis, scientists have experimental evidence that neurogenesis is enhanced by:
1) Physical exercise
2) Enriched environment
3) Specific types of learning
4) Certain drugs used as antidepressants
Current research is focused on learning about the new neurons’ contributions to the brain’s activities. Neurogenesis though is still an emerging field, thus far has provided insights about degenerative brain diseases.