Neurogenesis - can we keep learning as we age?
Brain image - new neurons in yellow
(Image credit: Baylor College of Medicine blog)
We learnt about the importance of neurons in our brains: every brain function (understanding, remembering, communicating, deciding) is performed by a (network of) neuron(s). The reason why we are capable of more complex thoughts as compared to all other animals is precisely because we have many times the number of neurons. The more neurons - the more the capacity for learning and knowledge.
For a long time, it was believed that humans produced neurons only up till age 3; thereafter, our neurons slowly die off as we age. But we now know - with the improvement of technology and a rather vicious battle within the scientific community over decades - for certain.
Adult neurogenesis happens - we continue to produce new neurons even into old age. Indeed this happens at a much higher rate than ever expected. For example, 3% of the neurons in an adult hippocampus are replaced monthly. And if you think about it, this makes perfect sense. The hippocampus is responsible for short-term memory and learning (remember the example of HM?) These new neurons are essential and integrative - they combine new information with your existing knowledge - this is where you learn subtleties: the difference between a crocodile and an alligator, between one Kaadashian and another (looks like this neuron hasn't developed for me), between Samoa and American Samoa, between "bank" - the financial institution and "bank" - the sides of a river.
So how can we "improve" our rate of neurogenesis?
The answer is simple:
- The more positive stimulus we provide our brains, the more effective the process of neurogenesis. The more we are exposed to new stimuli, the more we learn, the more we challenge ourselves to think through things and to really gain an understanding, the higher the rate of neurogenesis
* There is, of course, a limit to neurogenesis and neuroplasticity. If there were no limit, it would be possible even for those with brain damage to keep rewiring their brains towards normalcy.