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Week 5

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            In regards to the first paper, the VSDS seems like a good model for analyzing the effects of emotional stress, but I’m not convinced based on this one paper that it’s a good model for PTSD. I have a difficult time reading about animal models because instinctively, I relate everything back to humans. Not everyone who witnesses something traumatic has PTSD. Also, I wish they did more tests other than weight gain (which returned to control levels), social interaction, elevated plus-maze, and corticosterone levels. They measured social avoidance, but I’m curious if there was also an increase in distress. Why did they measure CORT levels after forced swimming rather than the traumatic reminder of a CD-1 mouse? I wish they measured changes in aggression or changes in sleep that are also characteristic of PTSD. However, I still think that it is a good model to use, as the second paper uses it to discuss neural pathways.
            I found it extremely interesting that in the conclusion of the second paper, the authors mentioned that understanding these circuits would provide insight into conditions like social anxiety and schizophrenia but failed to mention antisocial personality disorder. The two groups that observed a demonstrator being shocked on cue both exhibited increased freezing. Those two groups also had higher social interactions with the demonstrators, driven by the observation of distress, which the authors suggested could reflect empathy. Given that a hallmark characteristic of antisocial personality disorder is a lack of empathy, I’m very curious to see if this pathway has any implications in that disorder. I’m unsure if there are animal models for antisocial personality disorder. I would be curious to see the individual differences in this experiment of the mice who froze in correspondence to the cue to see if some mice inherently froze more for the demonstrator. Are there ever any mice that wouldn’t freeze at all? Or is this emotional contagion so necessary for survival purposes that a complete lack of it doesn’t exist in mice?

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