Empathy and emotional stress in mice observing stressful conditions- Sierra Smith


The Sial et al. paper was relatively easy to read and understand compared to the other recent papers we have been breaking down, but still holds many interesting insights into how to overcome the etiologically irrelevance of many PTSD or depressive measures, and overall how we can better model observational PTSD in mice for insights into human psychology. Although the Sial group convincingly demonstrates that emotional stress (ES) has similar effects on daily weight gain, serum cortisol levels, time spent in open arms of the elevated plus-maze test, and social interaction as physical stress (PS) in mice, I was concerned about the data presented on their reversal of these symptoms with chronic fluoxetine administration. Sial et al. present significant reversal of social interaction effects of emotionally and physically stressed mice after 1 month of fluoxetine treatment, but their error bars are quite large, especially in the fluoxetine treated PS group. I can attribute this to how antidepressant treatment varies significantly across different human patients, but I'd like to see this broken down more and maybe split these fluoxetine treated mice into two groups (high responsiveness to fluoxetine and low responsiveness to fluoxetine) for future experiments in order to identify what may be causing this differential social interaction after treatment.

I had a more difficult time unpacking much of the ACC to BLA neural activity recording data from the Allsop et al. paper, and look forward to in-class discussion to help clear up my interpretations of these figures. That being said, what I did think was particularly interesting about this paper was the exploration of genuine empathy-behaviors of observer mice. This was done through breaking up the experimental mice into EO, ES, NO, and NS groups to serve as multiple different experimental groups and control groups. The NO mice specifically demonstrated a genuine sympathy response, as the Allsop group showed that mice can exhibit significantly increased freezing responses after just witnessing a fellow mouse undergoing multiple shocks, even when they have never experienced a shock for themselves. They were also able to show that mice that observed another mouse undergoing shocks, regardless of whether they had experienced a shock themselves, showed increased social interaction and comforting behaviors when united with the mouse that underwent the shocks. This experiment seems to yield valuable and fascinating insight into what might potentially drive human empathy and human nature, in general.

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