Maternal separation effects on mother rodents' behaviour: A systematic review

Maternal separation (MS) is a widely-used paradigm to study the effect of early-life adversity on brain development and resilience to psychopathology. Most of the related literature focuses on MS impact on offspring, however, it should ideally also consider the impact of altered maternal behaviour caused by MS itself. This systematic review aimed at providing a comprehensive compilation of the effects of MS on key maternal behaviour aspects. We performed a keyword literature search using Boolean operators. Databases were searched between 2000-2018. Additional studies were included from manual search. Twenty-nine articles addressing the impact of MS on maternal behaviour and/or mothers' anxiety, depression-like behaviour, memory and consequences on underlying mechanisms. The methodological aspects and main conclusions were extracted from each study. This review shows that MS induces changes in dams. Results are particularly robust for increased anxiety and depressive-like symptoms, and altered maternal behaviours, predominantly for longer periods of MS. Finally, research in the field could strongly benefit from the establishment of guidelines to reduce the methodological inconsistencies here identified.