Early life manipulations alter learning and memory in rats

► Analyzed over 230 studies from 77 papers and classified into three task categories. ► Duration (brief or prolonged) has opposing effects on spatial/relational memory tasks only. ► Timing (during postnatal week 3 or not) led to opposing outcomes on spatial/relational tasks only. ► Performance was impaired in aversive conditioning and enhanced in inhibitory learning tasks by early life stress. ► Explained discrepancies in literature on early life stress and learning and memory.