Intrusive symptoms in post-traumatic stress disorder occur due to the generalization of contextual fear from the traumatic context to a safe context. This can be studied by producing a generalization effect using contextual fear conditioning. This project aims to investigate the effect of time and contextual features on contextual generalization in a mouse model of post-traumatic stress disorder. To do this, the fear responses of mice, measured by freezing levels, were tested one- or 15-days following contextual fear conditioning. This testing was done in the original conditioning context or a novel context with a different floor, wall shape, and wall pattern. Results showed a main effect of both time and context on the levels of freezing. Mice had increased freezing in the conditioning context, as well as after 15 days. There was no interaction between the two variables, indicating no contextual generalization. These findings suggest that the protocol used does not illicit contextual generalization but can work as a model for fear incubation. Yet, the results give insight into the role of time and contextual features in fear memory, which can be transferred to clinical settings when considering disorders such as PTSD. Future studies could investigate more remote time points, different contextual feature changes, as well as regional activation of areas such as the ventral hippocampus.


Alfredo Zuniga




Behavioral Neurobiology


post-traumatic stress disorder, contextual fear conditioning, fear memory, contextual generalization

Publication Date


Degree Granted

Bachelor of Arts

Document Type

Senior Independent Study Thesis


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