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Post 5: Vicarious social defeat and observational learning

Our studies this week discussed two different aspects of fear learning and conditioning in the contexts of vicarious stress and observational learning. I thought both groups of researchers did a fantastic job setting up their experimental groups and establishing control parameters. For instance, Sial et al (2016) specified how the social defeats were performed in a separate room so as not to influence control animals and how aggressor mice that consistently wounded the stressed/control mice were removed and not included in the data set. As I’ve mentioned before, I do not have hands-on experience with mouse research and having these details specified makes comprehending the articles much clearer. 

A few questions that came up: Allsop et al (2018) noted how experienced and naive observers showed increase interaction with the demonstrator mice, possibly due to ‘empathic processes’ or the ‘social buffering of stress’. Although not a primary focus of the paper, this was the first time these terms have come up in our discussions. What research methods are currently in practice to study empathy? Do studies ever focus on empathic behaviors or is it usually only something noted in addition to the main study?  

I was also intrigued by the conclusions made about the necessity of the ACC —> BLA circuitry for certain memory pairings. The paper notes that the BLA receives social information specifically during the cue presentation and it is therefore what ultimately makes the pairing stick. So, could the ACC potentially play a similar role for other types of memories that are not socially motivated? In some response, the authors later mention how they performed reciprocal inhibition (i.e. BLA —> ACC) and it did not affect observational fear conditioning. Perhaps there is some credence then to the reverse pathway playing a role in encoding different types of memories and experiences that might not be socially derived. 

Lastly, I kept thinking about the role that mirror neurons might play in these types of experimental setups. It is known that these neurons fire when we perform an action but also when we observe someone else performing that same action. With the limited knowledge I have about the topic, I think it is reasonable to think they must be somehow involved in the pathways discussed here and I'd be interested to know if anyone has experience or insight on that hypothesis. 

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