For decades, it was believed that the adult brain did not produce new neurons after birth. But that notion has been dispelled by research in the last ten years. It became clear by the mid- to late-1990’s that the brain does, in fact, produce new neurons throughout the lifespan.
This phenomenon, known as neurogenesis, occurs in most species, including humans, but the degree to which it occurs and the extent to which it occurs is still a matter of some controversy, says Tracey Shors, PhD, at Rutgers University.
“However, there is no question that neurogenesis occurs in the hippocampus, a brain region involved in aspects of learning and memory. Thousands of new cells are produced there each day, although many die with weeks of their birth.” Shors’ recent studies have shown a correlation in animal models between learning and cell survival in the hippocampus.
The hippocampus plays a critical roles in certain types of memory: consolidation of new memories, spatial memory, and navigation. Furthermore, the hippocampus appears to influence not only attention and learning, but also discrimination in determining when it is appropriate to learn one thing or another and, consequently, inhibiting extraneous associations while allowing meaningful associations to form.
The Learning Effect
“It is clear that learning can enhance the presence of new neurons in the adult brain,” says Shors, implying a “use it or lose it” phenomenon. “I want to stress that the cells that are rescued from death by learning were born before the learning experience. It is not the case, at least as far as we can tell, that learning produces more cells,” she says. Rather, their data indicate that the cells that were already there at the time of the training experience are affected by learning and thereby rescued from death.
“I am often asked whether learning and other cognitive activities will help prevent a decrease in neurogenesis or even the onset of diseases such as Alzheimer’s,” she says. “It seems prudent to assume so until we know different.”
Fred Gage, PhD at the Salk Institute shows us that using your brain is the best way to optimize your brain function:
“In the natural course of aging there is cognitive decline. We know we lose the ability to generate new neurons with age. We are currently trying to figure out how generate as many neurons as possible to potentially enhance learning or increase the amount of neurogenesis in adults.”
What Can You Do to Help Save Your Neurons?
- Develop a regular mental workout plan to match your physical workout.
- Eat well.
- Get plenty of physical exercise.
- Reduce your stress.
- Get enough sleep.