You can Grow New Brain Cells as you get Older
Kaplan & Sadock’s Comprehensive Textbook of Psychiatry Eighth Edition, Volume 1, Lippincott Williams & Wilkins 2005
In the last decade, there has been a fundamental shift in paradigm regarding the limits of neurogenesis in the brain, with important implications for neural plasticity, mechanisms of disease etiology and therapy, and possibilities of repair. Until recently, it has generally been maintained that new neurons are not produced in the brain after birth (or soon thereafter, considering cerebellar EGL); thus, brain plasticity and repair depend on modifications of a numerically static network.
Strong evidence to the contrary now suggests that new neurons are generated throughout life in certain regions – well documented across the phylogenetic tree – including birds, rodents, primates and humans. Because this is an area of intense interest and investigation, rapid progress should occur over the next two decades, likely altering models described herein.
From Dr. Braverman’s First Clark Randt Memorial Lecture on Cognitive Decline, 2008
Neurogenesis: A Brief History of Important Findings
“Once development is completed, the sources of growth and regeneration of axons and dendrites are irrevocably lost. In the adult brain, nervous pathways are fixed and immutable; everything may die, nothing may be regenerated.”
—Santiago Ramón y Cajal
When I attended medical school they told me that you could not grow new brain cells, but now we know we can. This finding is critical, because when we balance our brain chemistry we can get remarkable levels of neuropsychiatric and medical healing—improvements in our attention, memory and emotional well-being. Instead of becoming demented between ages 50 and 80, you can actually increase cell growth with natural antidepressants and other antidepressants properly utilized.
It was in the late 19th century that Ramón y Cajal, one of the fathers of modern neuroscience, concluded (erroneously, as we now know) that once we have completed development, neurons can no longer be made, and new pathways cannot be forged if something goes wrong in the original pathways. The weight of this conclusion is still felt today, as it was only with great reluctance that the first examples of neurogenesis and synaptic plasticity—the mechanisms by which new neurons are created and memories are stored—have been elucidated in the 1970s and ’80s. They were thought to be mistakes, anomalous—results of these primary studies were initially ignored, in part due to the lack of online search engines. Slowly, with more studies and improving communication, it was admitted that neurogenesis can occur, in very specific areas, like the hippocampus. Finally, we are beginning to uncover the plethora of mechanisms by which practically every part of the central nervous system can adjust, rewire and even replace itself.
This idea should not be so strange. Scientists have easily claimed that we have “new organs” after differing amounts of years, depending on the organ, as different cells replace themselves at different rates. But unfortunately—and due largely to the influence of the brilliant Ramón y Cajal—the brain was excluded from this paradigm. Admittedly, the brain’s rate of regeneration may be slower, due in part to the highly selective blood brain barrier (BBB), which can block or slow the passage of ingredients for trophic factors and other components necessary for regeneration and plasticity. However, with the proper knowledge, nutrition, drugs, and overall focus on how our brain works, we can facilitate our brain’s repair and replacement. We must first realize that the brain is not an island, dually isolated by the skull and the BBB. It is as alive as any other organ and can repair itself, grow new cells, and adapt to change.
With the newfound knowledge about how the brain works, scientists are learning more about the mechanisms of psychotropic medications. In 2000, a team at Yale University reported that antidepressants like fluoxetine (Prozac) increased neurogenesis in the hippocampi of rats. This was a huge step toward understanding how these drugs work, because for the longest time it was baffling to scientists why patients didn’t improve until they had been taking the medication for several weeks. However, it makes perfect sense for that amount of time to elapse before the effects are realized by the patient because new neurons can take several weeks to mature. This paradigm was further clarified by experiments by Rene Hen and colleagues at Columbia University, where they inhibited neurogenesis in a control group of rats on antidepressants by zapping their brains with X rays while giving the experimental group antidepressants and allowing for neurogenesis. The animals with the suppressed neurogenesis did not respond to the drugs. Now studies have revealed that running also stimulates neurogenesis. Erythropoietin, which is involved in the regulation of red blood cells, has been shown to enhance hippocampal neurogenesis. These are only some of the ways that have already been discovered to enhance our brain function, and there is still much more to be learned.
These findings should serve as a wakeup call for how we should approach personal care. Changes in the brain cascade outward and affect the rest of our body. If we target the brain, the body will benefit. Using our knowledge to support our brain’s phenomenal ability to rewire, repair and regrow, we can make the right choices in our diet, lifestyle and the medications we take when needed. This will positively affect our overall well-being, and assuredly enable us to stay healthy and vibrant into old age.
Antidepressants as Brain Salts and Brain Cell Regenerators:
Most people don’t realize tha antidepressants are just preservatives. Antidepressants preserve neurotransmitters and allow us to upregulate them. That’s why they are such effective substances for growing new brain cells. Since all aging people are either anxious, blue, depressed, insomniacs, or worse – psychotic and demented – you have to rejoice when you are just anxious and blue. Anxiety and the blues, which most of my patients suffer, are the first stages of the dementing process of aging. Trying to solve all of these problems psychodynamically is equivalent to giving talk therapy to an ant that has been stepped on. Aging is like being crushed, and it’s not solved in “chit-chat” at all. I am not saying that we can’t all benefit from a strong social network, religion, and spirituality, but the reality is that the purpose of religion is ultimately “no more death nor sorrow.” Extending life and enhancing brain health by preserving the brain, which is what antidepressants do, is the miracle of the craft of medicine.
Hormones and Neurogenesis:
Many of the same hormones that are associated with increasing brain processing speed (as measured by P300 wave latency on an electroencephalogram, or EEG) are also associated with neurogenesis. The following slides show some hormones that stimulate neurogenesis.
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Eric R. Braverman, M.D.
Dr. Braverman is a Summa Cum Laude and Phi Beta Kappa graduate of Brandeis University and NYU Medical School, did brain research at Harvard Medical School, and trained at an affiliate of Yale Medical School. He is acknowledged worldwide as an expert in brain-based diagnosis and treatment, and he lectures to and trains doctors in anti-aging medicine.