New Brain Process Responsible for Long Term Stress Identified

Andrew Goldbaum CE1 9/13/18 C Even

Velasco, Emily. “New Brain Process Responsible for Long Term Stress Identified.” Neuroscience News, NeuroscienceNews.com, 13 Sept. 2018, neurosciencenews.com/long-term-stress-process-9862/.

Researchers at Semmelweis University of Budapest, the Swedish Karolinska Institute, Yale, and the Medical University of Vienna discovered a new brain process responsible for delayed stress and the long-term effects of stress: What’s already known is that a specific group of neurons triggers two processes in the hypothalamus (region involved in homeostasis, sleep, and emotions). Both processes occur almost immediately after stress and are short lasting, one ultimately releasing hormones in the blood from the adrenal glands, the other an immediate neural attachment to the prefrontal cortex (a behavioral moderation “center”). This international team has discovered a more delayed and long-lasting response coming from the same group of neurons responsible for the first two. Ciliary Neurotrophic Factor, a molecule crucial for nervous system development and maintenance, diffuses in brain fluid as it approaches stress neurons. Since diffusion in the brain fluid is slow compared that in blood, CNTF lingers in the fluid and approaches the stress center for a long time, keeping the prefrontal cortex alert. These findings are the missing piece of the puzzle of stress response: now that the nervous system aspect of long-term responses to consistent environmental threats is elucidated and since molecular pathways were introduced in this research that can be drug targets for pharmacologists, an opportunity has opened  to treat problems associated with long-term stress, such as PTSD, consistent acute stress, chronic stress and burnout.

Since it is no longer a given what our role in the world is (hunter or gatherer in a tribe) and agriculture and technology have given us more free time to stress over self esteem and achievement of some spiritual purpose, and since there is so much competition, fluctuation, and choice with regards to one’s job, hobbies, finance and relationships; life may be easier and more cushy than it was for our caveman ancestors, but it is also significantly more complicated and arbitrary. Therefore, despite more comfort and less threat of death, we now live an environment conducive to dysfunctional levels of long-term stress. We are a gift of natural selection, but for an environment that mainly existed millions of years ago. Due to a more humane, human-run world, natural selection no longer occurs, so we will have to find artificial selection methods for preferable traits. This, thus far, has produced CRISPR-CAS9 and other gene editing techniques, but even this is in vain if the brain is still a complicated frontier: if we did not even know about where and how this stress response occurs, then how could we have possibly targeted and replaced the genes responsible with healthy ones? Because of this, any elucidation of brain function such as this is not just novel for treatment, but for the artificial selection and improvement of our species in decades to come.

Overall, this is a very well-written summary of these new findings that is both easy to understand and substantive: it described the broad reason for a slower response, molecular diffusion in the brain being slower than in blood, without going into too much detail about advanced topics, such as the specific pathway of neurons and action potentials as well as what triggers these specific molecules. It also clearly elucidates the role and importance of this finding: new molecular mechanisms found and knowledge of how long term stress begins in the nervous system. However, to more clearly explain what leads to the difference in this mechanism from the same neurons, insight should be provided into what triggers the release of the molecule by those neurons.