A growing body of neurological research since the 1960's suggests that even after we mature, cells in our brains are proliferating and differentiating into specific functions through a process known as neurogenesis, particularly in the hippocampus. This brain region is related to emotions, memory, and possibly even our sense of morality, according to researchers Anand and Dhikav. Furthermore, research suggests this process may be influenced by external stimuli, including cannabinoids.
One survey of previous studies concluded that ingested cannabinoids regulate cellular plasticity (the ability of stem cells to become different types of cells and structures, in this case neurons) and survival in the same way as antidepressants, by acting on the body's endocannabinoid system. The authors surmised that probably both cannabinoids and antidepressants modulate cell signaling pathways to increase the growth and differentiation of neurons in the human hippocampus. They propose that this process is what is responsible for regulating symptoms. Here is an important link between CBD oil's potential therapeutic properties and real-world treatments for mental and behavioral health.
Here I would like to emphasize that the global scientific community has not yet reached a consensus on exactly how this neurogenic effect plays out for us in day-to-day life. But according to Prenderville, Kelly, & Downer, writing in the British Journal of Pharmacology, "the weight of evidence indicates that impaired neurogenesis is associated with depression and cognitive impairment. Pharmacological targeting of the cannabinoid system as a regulator of neurogenesis may prove a fruitful strategy in the prevention or treatment of mood or memory disorders." Cannabinoids, including CBD, are currently being investigated by teams all over the world so that we can better understand their effects and apply them in the treatment of specific conditions.
For example, researchers using a rat model for Alzheimer's Disease found that the cannabinoid receptors CB1 and CB2 are related to the progression of Alzheimer's, and that "cannabinoids succeed in preventing the neurodegenerative process occurring in the disease". While rodent models do not translate directly to humans, there are such significant similarities between all mammalian brains that these results are an important starting place for further human-specific research. Also of note, these researchers used very powerful synthetic cannabinoids that would likely produce adverse effects in humans, while CBD is generally well-tolerated with no adverse effects. So while the results may not directly translate, it was a very promising finding.
The endocannabinoid system's neurogenesis-inducing effects are involved in profoundly varied conditions, of which Alzheimer's is only one example. Researchers studying anxiety using a mouse model concluded that "the anxiolytic effect of chronic CBD administration in stressed mice depends on its proneurogenic action in the adult hippocampus by facilitating endocannabinoid-mediated signalling". Simply put, this means the authors concluded that long-term CBD use helped mice be less anxious specifically because of its effect on hippocampal neurogenesis. On the benefits of CBD specific to humans, the study's authors wrote that CBD "exerts therapeutically promising effects on human mental health such as inhibition of psychosis, anxiety and depression", perhaps in a way similar to the mechanism of action in mice. Again, further research will clarify the relevance of these results to the day-to-day treatment of human mood and memory disorders.
There appears to be a growing body of evidence that cannabinoids, including CBD, exert a direct influence on our ability to grow new neurons in the area of our brains involved in memory, learning, and emotions (and possibly even morality). These findings have important implications in the treatment of Alzheimer's and other conditions, and this area of research will doubtlessly expand in coming years. Hopefully we can look forward to novel treatments for a wide variety of conditions using cannabinoids to replace those conventional therapies that are ineffective or can cause harmful side effects for many. Stay tuned for that!
neurogenesis - the process by which nervous system cells, known as neurons, are produced by neural stem cells. (Wiki)
neuroplasticity - The brain's ability to reorganize itself by forming new neural connections throughout life. (MedicineNet)
hippocampus - the elongated ridges on the floor of each lateral ventricle of the brain, thought to be the center of emotion, memory, and the autonomic nervous system. (Oxford)
cannabinoids - a class of diverse chemical compounds that act on cannabinoid receptors in cells to alter neurotransmitter release in the brain. (Wiki)
endocannabinoid system - a biological system composed of endocannabinoids, which are endogenous (existing in the body naturally) neurotransmitters that bind to cannabinoid receptors, and cannabinoid receptors that are expressed throughout the mammalian central nervous system (including the brain) and peripheral nervous system. (Wiki)