Identifying the Effects of Different Juvenile Stress Protocols on Adult Fear and Anxiety-like Behaviours in C57BL/6J Mice

Both chronic1–3 and sub-chronic4,5 stress experienced in early life are associated with the development of psychopathologies such as anxiety and greater adulthood stress susceptibility, along with atypical medial prefrontal cortex (mPFC)-amygdala circuitry maturation6–8. mPFC-amygdala circuitry, which mediates anxiety-like behaviours9,10, undergoes significant developmental changes in juvenility, specifically11,12. Therefore, it is thought that juvenility might constitute a period of neurodevelopmental sensitivity to the effects of stress for behaviours dependent on mPFC-amygdala circuitry. To test this theory, our study targeted the precise ages in juvenility that are associated with significant mPFC-amygdala circuit maturation in C57BL/6J mice with both chronic and sub-chronic stress. However, we failed to detect a clear effect of stress on anxiety-like behaviour, fear learning and extinction, and susceptibility to stress when the mice were tested in adulthood. These results do not support juvenility as a sensitive period to the effects of stress for behaviours mediated by mPFC-amygdala circuitry.M.A