Observational Learning Paradigms


This week we look at two paradigms of observational learning in mice. The first paradigm, by Sial et. al, demonstrated that mice can effectively learn by observing physical defeat of other mice, providing a chronic instead of physical model of stress. Importantly, the results showed that the effects of emotional stress are not unlike those of physical stress in many aspects. This demonstrates the value of this paradigm as an approximation for a model of PTSD which comes as a consequence not only of physical but also emotional stress. Furthermore, a recent publication by Iñiguez and colleagues (2018) making use of the same stress model demonstrated that emotional stress can be effectively induced in female mice. The physicals stress paradigm is not applicable to females because male mice will not attack them, and this paradigm provides a novel manner for research into stress in females to be conducted, which is severely lacking due to the limitations of previous paradigms.
                The second paradigm of observational learning involved the observation of a shock instead of physical defeat. In their study, Allsop and colleagues (2016) investigate the brain pathway dynamics involved in observation learning in this paradigm. Using very well though out methodology and manipulations, the authors effectively demonstrated that a neural pathway from the anterior cingulate cortex to the basolateral complex of the amygdala is essential for observational learning but not for classical conditioning. This suggests that the ACC is exerting control over fear learning in the amygdala by encoding the predictive value of the cue, via the potentiation of reduction of signaling to the amygdala if the cue is predictive or non-predictive respectively. Together results from the two studies demonstrate that observational fear learning, while resulting in much of the same behavioral responses as classical fear learning, is dependent, at least in part, on distinct neural circuitry. Finally, these studies demonstrate the value of these paradigms in the study of diseases involving abnormal observational fear, such as PTSD; furthermore, these paradigms are applicable to female mice, for which research is lacking and is equally important due to the sex dimorphisms observed in many other areas of research in neuroscience.  

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