Storing maternal memories: Hypothesizing an interaction of experience and estrogen on sensory cortical plasticity to learn infant cues

• New research is uncovering sensory cortex’s role in maternal behavior and memory.
• Infant cues are processed by sensory systems for recognition and discrimination.
• Experience-dependent cortical plasticity helps store an engram of infant cues.
• Maternal context provides natural paradigm for sensory cortical plasticity research.
• Estrogen-dependent mechanisms hypothesized to modulate sensory cortical plasticity.

Much of the literature on maternal behavior has focused on the role of infant experience and hormones in a canonical subcortical circuit for maternal motivation and maternal memory. Although early studies demonstrated that the cerebral cortex also plays a significant role in maternal behaviors, little has been done to explore what that role may be. Recent work though has provided evidence that the cortex, particularly sensory cortices, contains correlates of sensory memories of infant cues, consistent with classical studies of experience-dependent sensory cortical plasticity in non-maternal paradigms. By reviewing the literature from both the maternal behavior and sensory cortical plasticity fields, focusing on the auditory modality, we hypothesize that maternal hormones (predominantly estrogen) may act to prime auditory cortical neurons for a longer-lasting neural trace of infant vocal cues, thereby facilitating recognition and discrimination. This couldthen more efficiently activate the subcortical circuit to elicit and sustain maternal behavior.