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Week 5: PTSD and Vicarious Fear Condtioning

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I’ve been interested in vicarious/social fear learning since I first took the Neuropsychology of Fear in Spring 2017. I’ve been interested in how fear can be passed down through observational learning and the things that influence it. As each of the papers this week build on one another, I want to consider the role of other sensory stimuli in the ACC -> BLA circuit. Ana Pereira from Marta Moita’s lab published a paper a few years ago about the role of silence in the social transmission of fear. They did a similar behavioral paradigm as the Allsop and had an experienced observer watch another rat undergo fear conditioning. They concluded that the rats relied on auditory cues in the environment, namely the silence resulting from the absence of movement in the conditioned rat.  Given the necessity of ACC cells in the social transmission of fear as Allsop concluded, I’m wondering if these two notions relate to one another.  The cingulate cortex is related to many autonomic and cognitive functions, one being hearing and attention. I’d be interested to see if there could be a way to study the connection of the role of auditory cues and the ACC -> BLA pathway.  Perhaps one could replicate the Pereira methodology of conducting observed conditioning in the dark and playing/stopping recorded sounded of rat movements at various times while stimulating or inhibiting the ACC -> BLA pathway in both conditions. This could determine if and what role auditory cues play in the transmission of fear. If the cingulate to BLA pathway is modulated in some part by auditory cues, then freezing would be affected in the absence of silence but not in the absence of visual cues. I’d be interested to see if there is a way to understand how the transference and recognition of other sensory stimuli affect this particular pathway.

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