Why do some people seem to shine in the face of stress while others crumble? I have a friend who manages a high-profile event company with ease, and another who will break down and tantrum if she spills the contents of her purse. Recent research published in the online version of Cell point to a potential blueprint of our brain: specific adaptations in the brain’s response to stress may affect our resilience.

The initial work was done on mice, however, several major components in their brains are similarly constructed to human brains (we are both mammals, after all) so keep reading. Researchers found differences in the rate of impulse-firing by cells that make the chemical dopamine. Those animals that were vulnerable to stress (seen by avoidance of social interaction with other mice after a stressful stimulus) had excessive rates of impulse-firing in their brain. Those mice that adapted well maintained a normal rate of firing. These higher rates of impulse-firing led to an increase in a certain protein (BDNF) linked to poor stress adaption. Those that were resistant to stress did not have the same amount of protein. Furthermore, mice that were resistant to stress were found to have a higher level of gene activity in the brain, meaning that they had a whole array of biochemical events in the brain working to offset poor stress coping. All of this happens in the reward areas of the brain, which promotes repetition of acts that ensure survival (meaning, this process is going to happen a lot).

So, why is this important? For starters this shows a potential biological explanation of stress coping. Extending this line of research to humans, those who don’t respond well to stress may be hard-wired that way. Their brains simply can’t offset the vulnerability mechanism. In another study, the researchers examined (deceased) human brain tissue of persons prone to depression , and compared it with the stress-vulnerable mice. In both cases they found higher amounts of this certain protein, providing a potential link to stress and depression in the brain.

Understanding the biological underpinnings of a stress response helps researchers pinpoint areas for intervention. The scientists in this study were able to turn stress-vulnerable mice into stress-resistance mice by blocking signaling done by the identified protein in the brain. Future research may uncover how to enhance the protective resilience mechanism in humans suffering from post-traumatic or high levels of stress and depression.

Further Reading:

Krishnan V, Han M-H, Graham DL, Berton O, Renthal W, Russo SJ, LaPlant Q, Graham A, Lutter M, Lagace DC, Ghose S, Reister R, Tannous P, Green TA, Neve RL, Chakravarty S, Kumar A, Eisch AJ, Self DW, Lee FS, Tamminga CA, Cooper DC, Gershenfeld HK, Nestler EJ. Susceptibility and Resistance to Social Defeat Are Mediated through Molecular Adaptations in Brain Reward Regions. Cell, online Oct. 18, 2007.

Adapted from the NIH Press Release