Week 5, Allsop et al. & Sial et al. Observational Learning

This week the two papers, first by Sial et al. and second by Allsop et al. studied two different paradigms and different hypothesis however they utilized certain paradigms to achieve the same underlying effect of observational learning and the ability for us to observe that in rodent models. Right off the bat, I was quite overwhelmed with the amount of manipulation that went into the paradigm discussed in the Allsop et al. paper as compared to Sial et al.

Allsop et al. used a variety of test and control groups to develop a paradigm to study the projections and nuclei that may be involved in observational fear learning. Sial et al. however, used a much more simplified chronic social defeat stress paradigm (CSDS), one that has been seen many times before in our previous articles, along with a witness component to factor in the ‘observational’ aspect (VSDS)

I have been thinking a lot about ethological validity lately in terms of how a laboratory setting could affect the natural and endogenous behaviors of organisms. Ethological validity is a major confounding variable that most paradigms try to account for. Sial et al. seem to have developed a novel method, the VSDS that not only uses a tried and tested model to induce anxiety in mice but to also account for things such as “emotional stress” in an animal model. This method to me seemed most valid in terms of models for observational learning and well as PTSD. I had a few qualms with the paradigm chosen by Allsop et al. Firstly, they had no data to support the idea that an organism can learn through observation without ever having experienced the stimulus or situation themselves and this is seen in their data as NO (naive observer) group that had never experienced cue-shock pairings did not change behavior after viewing a demonstrator attain a cue paired shock. This is in direct contrast to their opening statement saying “observational learning. Individuals (can) learn without directly experiencing the pairing or predictive cue and punishment.” Their paradigm is focused on a classical conditioning response which in my opinion lacks ethological validity and with the bulk of behavior being a result of classical conditioning and not pure observational learning. It is too highly manipulated, and although it does provide a model in which former experience can lead to recall due to observation, it does not seem as robust as the data shown by Sial et al. where it was quite clear that emotionally stressed mice were displaying similar behaviors in stress tests to physically stressed mice. This model very succinctly showed that observation alone can induce a change in behavior as seen not only by their cortisone changes but as well as a social interaction test and elevated plus maze. 

Allsop et al, however, did take it one step further, a step I would have liked to see done by Sial et al., they used optogenetics to then study the neuronal projections from the anterior cingulate cortex to the basolateral amygdala, I would have much rather liked to have seen these optogenetic studies done using the VSDS paradigm which, to me, seemed a much better model for PTSD as well as observational learning. I would like to see if the projections activate in the same way and the ACC and BLA nuclei are necessary components of acquisition for fear learning. If this pattern of activation was conserved in the VSDS model, it would provide a concrete argument for the functionality of these projections and further validate the use of the VSDS model created by Sial et al.