We used to believe that you’re born with all the brain cells you will ever have…but we were wrong. It turns out that we can create new brain cells and new connections between brain cells throughout our entire lifetime. We do this through two processes: neurogenesis and neuroplasticity.
Neurogenesis is the process of forming new neurons in the brain. Most new brain cells are formed in utero, but neurogenesis continues in certain brain regions after birth and throughout our lifespan. Adult neurogenesis is now accepted to be a normal process that occurs in healthy brains.
The science of neurogenesis shows us it is possible to create neurons that improve thinking and memory skills forever.
Adult neurogenesis happens in the hippocampus, which is the part of the brain responsible for learning information, storing long-term memories, and regulating emotions. Even in old age, the brain produces around 700 new neurons in the hippocampus each day. This may seem like a drop in the bucket considering there are literally billions of neurons in the human brain…but with effort, we can increase that number and even restore key brain functions that have been lost.
Intentionally triggering the process of neurogenesis may help protect against Alzheimer’s and other dementias since brain cell death is part of the disease process. It can also treat and prevent depression, which shrinks the hippocampus.
One way to stimulate neurogenesis is sustained aerobic exercise. Endurance exercise releases brain-derived neurotrophic factor (BDNF) which is known to stimulate the process of neurogenesis. Frequent sex and other stress-relieving activities also stimulate neurogenesis. Chronic stress blocks the process of neurogenesis and so any pleasurable, stress-relieving activity helps facilitate the creation of new brain cells. Brain exercises that emphasize the unexpected — called “neurobics” — are another way to stimulate neurogenesis.
Neuroplasticity is the capacity for our brain cells to change in response to our behavior. Neuroplastic change occurs at three levels: chemical, structural, and functional.
Neuroplastic chemical change happens in the early stages of learning something new. It mainly affects short-term memory and short-term improvements in motor skills. To illustrate, imagine taking up woodworking as a new hobby. The first stages of learning woodworking can be clumsy because the hands and eyes and brain aren’t used to the tools, the motions, or the sensory input.
But after a little while, the motions become smoother and the tools more familiar. We get better with practice, but we still haven’t mastered our craft. This is the structural change that happens when neurons change their connections. Structural neuroplastic change requires more time and effort than chemical change but the changes run deeper, affecting long-term memory and long-term improvements in motor skill.
Fast-forward one year down the road. We know what to do with all the tools in our woodworking workshop. We can look at a piece of wood and know exactly how to bring out its full potential. We don’t watch YouTube videos to see how to crosscut or use a mitre saw…in fact, we’ve started making our own videos to share our craft with others. In neuroplastic terms, what we have experienced is functional change. We have created entirely new brain networks that we have used again and again, making them more effective and more efficient. Functional neuroplastic change is deep and lasting and goes beyond conscious thought.
Like muscles, the more we exercise our brain, the stronger it becomes. Research shows that five components are necessary to induce neuroplastic change and strengthen our brain. The first of these is challenge and novelty. For neuroplastic change to occur, we must learn something new that is not too easy to learn. Neuroplastic change also requires intention. This means that the new skill we are learning must have meaning, relevance, or otherwise be important to us. If we don’t find it personally rewarding, it won’t do the trick.
The third ingredient for neuroplastic change is specific attention. Only by focusing on the exact task and skill will we realize improvement. The fourth requirement is repetition. Short bouts of intense repetition create new connections, but one-and-done won’t cut it. Finally, we have to practice our new skill regularly and over a long enough time period for the change to move beyond chemical, beyond structural and into the realm of functional change.
To reduce risk of dementia, stimulating our brain must become an everyday thing. Learning a new and challenging skill such as woodworking or how to play the piano is one piece of the puzzle. The other is integrating novel challenges into things we do every day. Something as simple as learning to brush our teeth with our non-dominant hand or wearing our watch on our other hand stimulates the brain to make new connections. We do the same thing when we choose to shop in different grocery stores or take new routes when driving.
By intentionally and regularly swapping our habitual behaviors for ones that are new, awkward, and difficult we create opportunities for new brain cells to be born and for new connections to be made. Harness the power of neurogenesis and neuroplasticity today for a better tomorrow!