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In this day and age where stress affects everyone, it is important that more research is done about stress biomarkers. Constant exposure to chronic stress can lead to serious mental illness such as anxiety and depression. Stress can affect individuals differently depending on their biological makeup. Some individuals might respond negatively to stress while other might respond positively and form resilience. According to Thomas Larrieu’s research, stress plays a significant role in a range of mental illnesses. Yet, stress does not disturb everyone equally; while some individuals become depressed when dealing with continual hardships, others acclimate and endure. Larrieu and his team set out to show the risk influencers and biomarkers for susceptibility to social status depression.

The findings from an experiment lead by Thomas Larrieu helps us understand why individuals have different responses to stress. The experiment primarily tested if social status effects susceptibility to stress in adolescent mice. In particular, the researchers exposed mice to chronic social defeat stress (CSDS). Before finding out the effects of social status on stress, the researchers had to distinguish the subordinate mice from the dominant mice. Within the mice population, to initiate social status, the young mice were placed into cages of four for seven weeks before exposure to any stress. After seven weeks they measured social ranking by performing several tests on the mice. One test, categorized as a social confrontation tube test; consisted of putting two mice from the same social environment in the middle of a tube. The mice were previously trained to get out of the tube by walking forward. For the test, the mouse that walked forward and essentially made the other mouse back out of the tube was considered the dominant mouse, the mouse that was forced to walk backward was the subordinate mouse. With this social test and several others, the researchers were able to determine the social ranking of the mice. They ranked the mice from 1 to 4, 1 and 2 being dominant and 3 and 4 being subordinate.

After the researchers established the social hierarchy of the mice, they started to expose the subjects to different scenarios that would induce stress. When dominant and subordinate mice were exposed to a very aggressive mouse from another species for ten days, the dominant mice showed social avoidance whereas subordinate mice were not significantly affected. Researchers then analyzed the effects on the brain when mice felt defeated and showed signs of depression. The researchers measured the concentration of metabolites in nucleus accumbens. The nucleus accumben plays a role in motivation and reward that would affect whether an individual is resilient or not (Schlaepfer et al.). The more activity there is in the nucleus accumbens, the less likely the individual is susceptible to depression. The experiment showed that subordinate mice have more activity in their nucleus accumbens when exposed to stress than dominate mice do. From their findings, the researchers discovered the biomarkers for resilience to stress in mice. The resilience to stressful situations comes from the amount of activity in a nucleus accumbens.

After discovering the correlation between social status and susceptibility to stress, the researchers did recognize the fact that some mice could have been more susceptible to stress just from having trait anxiety, which could have affected the results. Nevertheless, they hope that their findings can help with the progress of researching vulnerability to stress. Now that stress biomarkers have been detected in mice, there is a greater possibility that scientists will find ways for humans to become more resilient to stressful situations.

I did not find it hard to summarize the research article. I found it harder to summarize the pop culture article. I thought the research article made more sense to me, so I was able to summarize it with no problems. The research article went into to detail about how the researchers came to their conclusions, whereas I was a little skeptical about the pop culture article because I don’t think there was enough information. I had to leave out other tests the researchers conducted to determine their social ranking. I also left out other procedures they did to induce stress on the mice. I left those components of the research out because I did not feel that was the crucial points that needed to go into the summary. I wanted the reader to have one example of how the researchers assigned social status and how they exposed the mice to chronic social defeat stress. While reading the pop culture article, I questioned what procedures the scientists conducted to figure out the mice social hierarchy. I also wondered how they were exposing the subjects to stress. It was important that I elaborated on some of the researcher’s procedures that lead them to their conclusions to reduce skepticism from the reader.

I did not think much about journalism before this assignment. I am more skeptical about reading pop culture articles. But now, if the author does leave out some vital information I will be a little sympathetic, knowing that they have a word count and not all the information can go into the article.