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Post 5: Observation paradigms as a model of emotional stress and observational learning

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In neuroscience and abnormal psychology today, the disregard of female animal models is considered one of the major oversights of research that has been otherwise foundational in understanding many neurological disorders. While reading Sial et al. (2015) and Allsop et al. (2018), this type of sex bias seemed especially evident and seemed to me an exemplar of studies that would be improved by the inclusion and analysis of female subjects. While all research aimed to apply to both sexes should include both sexes, the lack of female representation in these papers was especially concerning to me because they explicitly consider emotional stress and empathy. Past research has shown that male and female rodents have very different responses to stress, and I would posit that these responses are especially distinct for emotional stress (such as observational stress and learning seen here) compared to those due to pain or injury (such as shocks or injuries due to social defeat). Additionally, females tend to show more apparent empathy due to maternal behaviors. Sial et al. did call out the need for and utility of females in their research but had not yet created a similar paradigm that could include females. In the case that Sial et al. were able to adapt their paradigm for female mice to observe, I am curious whether the degree of stress and stress responses would be higher if a female mouse observed her offspring being socially defeated. Similarly, I would be interested in seeing the results of experiments similar to these in even more affiliative species and/or between mates, as they may have stronger stress responses to observing a conspecific experience trauma.

Another theme that has been uncovered during our class discussions that was evident in Sial et al. and Allsop et al. was the efficacy of behavioral measures of emotions and models of disorders. While Sial et al. did mention that the experiment can serve as a model for various stress-induced neuropsychiatric disorders, there was a distinct focus on PTSD, as witnessing traumatic events alone can cause PTSD in humans. However, the paradigm did not seem to specifically apply to PTSD, as emotional stressors are simply another type of stressor, and stressors are known to cause anxiety and depression-like behaviors in mice. Similarly, the use of freezing as a measure of fear in Allsop et al. brings up the recent debate of whether or not this behavior truly is indicative of fear. While we cannot perfectly model human psychological conditions in rodents, these papers take an important step toward modeling emotional stress and ethical behaviors. 

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