The hippocampus is necessary for enhancements and impairments of learning following stress.

The hippocampus is often considered to be an important site for stress and learning interactions; however, it has never been demonstrated whether these effects require the hippocampus. In the current study, hippocampal lesions prevented both enhancements of learning after stress in male rats and impairments of learning after stress in female rats without disrupting learning itself in either sex. Thus, the hippocampus is necessary for modifying learning in males and females after acute stressful experience.