Introduction to Neurogenesis
Up until the late 1990s, researchers believed that the growth of brain cells ended in our early 20s. They thought that after a certain age, the number of brain cells was fixed, and once we lost them, we couldn’t regrow them.
However, researchers now know that is wrong, and it’s actually possible to grow new brain cells.
Your brain doesn’t need to degenerate.
In fact, your brain can produce new cells throughout your entire life, and you can create new, healthy brain cells at any age.
The creation of new brain cells is called neurogenesis.
What is Neurogenesis?
Neurogenesis is the birth of new neurons from neural stem cells in the brain.
It’s essentially how the brain renews and upgrades itself.
Your rate of neurogenesis, or how frequently you make new brain cells, is one of the most important biomarkers of brain health.
A low rate of neurogenesis leads to cognitive decline, memory problems, and anxiety and depression.
On the other hand, a high rate of neurogenesis leads to enhanced cognition, rapid learning, quick problem solving and robust resilience to emotional stress, anxiety and depression.
Luckily, it’s possible to significantly increase your brain’s rate of neurogenesis and improve the quality of your life.
And I’m going to show you how.
The Scientific History of Neurogenesis
Early neuroanatomists in the late 19th and early 20th centuries considered the brain fixed and absolutely incapable of regeneration.
Then in the 1980s, other researchers discovered neurogenesis in mammals (324-326).
Finally, in the 1990s, neurogenesis became mainstream, as neurogenesis was found in the hippocampus of primates and humans, including elderly individuals (327-330).
In 2005, researchers stated that “the discovery that the adult mammalian brain creates new neurons from pools of stem-like cells was a breakthrough in neuroscience”.
How Are Brain Cells Made?
Humans form new neurons in the hippocampus. The hippocampus is a major component of your brain. You have one hippocampus on each side of the brain.
One end of your hippocampus helps you regulate your emotions and manage stress, anxiety and depression.
The other end controls logical thinking and cognitive function, including learning and memory.
Your hippocampus is full of neural stem cells, which give birth to new brain cells.
Twenty years ago, no one even knew this was even possible.
So this is cutting-edge stuff.
And the research is evolving every day.
In fact, cutting edge research suggests that neurogenesis doesn’t just take place in the hippocampus. It likely takes place in other areas of the brain, including the striatum, olfactory bulb, cerebral cortex, septum, spinal cord, amygdala, hypothalamus and white matter.
On top of this, researchers are discovering that new brain cells that are generated in the hippocampus can move to other areas of the brain!
The migration of brain cells to non-neurogenic areas of the brain suggest that the brain might have much more potent regenerative capabilities than previously imagined.
Researchers continue to learn how to grow new brain cells – which is why I will continue to update my Grow Your Brain program as time goes on.
But even today, we know there are certain dietary, lifestyle and environmental factors that affect your rate of neurogenesis, which I discuss in my three-part program.
Conditions That Will Benefit from an Increased Rate of Neurogenesis
Anyone can benefit from an increased rate of neurogenesis, but damage to the hippocampus and reduced rates of neurogenesis have been discovered in patients with neurodegenerative diseases, mood disorders, and other cognitive dysfunctions.
And research shows that high rates of neurogenesis are associated with higher cognitive function, better memory and faster learning, emotional vitality and resilience, enhanced overall brain function, and protection from stress, anxiety, and depression.
Many researchers believe stress is one of the most significant factors that contribute to the onset of depression. Stress can lead to a reduced rate of neurogenesis because brain cells in the hippocampus are sensitive to stress.
In fact, a lot of studies are now showing that depressed patients often have a low level of neurogenesis, and SSRI antidepressants work because they increase neurogenesis in the hippocampus. Studies have shown that antidepressants don’t work when neurogenesis is blocked by irradiation.
On top of this, it usually takes new brain cells three to six weeks to mature, and that’s about as long as it takes for antidepressants to start working for most people.
Depression isn’t the only mental illness that benefits from an increased rate of neurogenesis.
Compounds that increase neurogenesis can also help treat anxiety disorders, including post-traumatic stress disorder and panic disorder.
Studies suggest that people with schizophrenia have a reduced hippocampus volume, which is believed to be caused by a reduction in adult neurogenesis.
Concussions and Traumatic Brain Injury
For those struggling with a concussion or brain injury, there is hope.
Researchers have observed neurogenesis in the regions of the brain where neurogenesis normally does not take place.
But after injury and death of brain cells in non-neurogenic regions of the brain, there have been reports of new brain cells being generated in other regions of the brain (like the hippocampus) and then migrating to non-neurogenic regions (320-323).
Neurogenesis allows your brain to age gracefully, as new brain cells work to replace the brain cells that inevitably die.
In fact, in patients with Alzheimer’s disease, the hippocampus is one of the first areas of the brain that gets affected.
And one study has found that increasing neurogenesis may be able to help treat Parksinon’s disease.