BDNF and depressive disorder: Interestingly, several studies described BDNF as a marker for changes in different social behaviors, such as depression and anxiety (Berton et al., 2006; Dalle Molle et al., 2012; Maynard et al., 2015; Mendez-David et al., 2015; Moser et al., 2015), which could also impact maternal behavior.