This 2014 rodent study gave further details that:

“Chronic stress, which can precipitate depression, induces changes in the architecture and plasticity of apical dendrites that are particularly evident in the CA3 region of the hippocampus.”

Other studies on the hippocampus CA3 region include:

• Problematic research on the hippocampus part of the limbic system
• Early emotional experiences change our brains: Childhood maltreatment is associated with reduced volume in the hippocampus
• Our memories have contexts with specific places and times

http://www.pnas.org/content/111/45/16130.full “Role for NUP62 depletion and PYK2 redistribution in dendritic retraction resulting from chronic stress”