Becoming a better parent: Mice learn sounds that improve a stereotyped maternal behavior.

While mothering is often instinctive and stereotyped in species-specific ways, evolution can favor genetically "open" behavior programs that allow experience to shape infant care. Among experience-dependent maternal behavioral mechanisms, sensory learning about infants has been hard to separate from motivational changes arising from sensitization with infants. We developed a paradigm in which sensory learning of an infant-associated cue improves a stereotypical maternal behavior in female mice. Mice instinctively employed a spatial memory-based strategy when engaged repetitively in a pup search and retrieval task. However, by playing a sound from a T-maze arm to signal where a pup will be delivered for retrieval, mice learned within 7 days and retained for at least 2 weeks the ability to use this specific cue to guide a more efficient search strategy. The motivation to retrieve pups also increased with learning on average, but their correlation did not explain performance at the trial level. Bilaterally silencing auditory cortical activity significantly impaired the utilization of new strategy without changing the motivation to retrieve pups. Finally, motherhood as compared to infant-care experience alone accelerated how quickly the new sensory-based strategy was acquired, suggesting a role for the maternal hormonal state. By rigorously establishing that newly formed sensory associations can improve the performance of a natural maternal behavior, this work facilitates future studies into the neurochemical and circuit mechanisms that mediate novel sensory learning in the maternal context, as well as more learning-based mechanisms of parental behavior in rodents.

Using the pup retrieval instinct as reinforcement for efficient auditory learning in mice.

There is growing interest in the mechanisms for natural sensory learning in pro-social contexts. Studies using a maternal model of social behavior in the mouse have provided new insight into the auditory processing of behaviorally relevant pup vocalizations, which are used as communication signals to elicit pup retrieval behavior by adult females. Whether neural and behavioral plasticity in response to these vocalizations reflect auditory associative learning linking the sounds to pups, versus simply a change in maternal responsiveness to evolved vocal signals, remains an open question. Here we describe a T-maze paradigm to track auditory learning as we pair an initially neutral, non-ethological stimulus with delivery of a pup for retrieval, which is intrinsically reinforcing for rodents.•Training is rapid and completely appetitive.•Over a period of 7 × 50-minute daily training sessions, animals increasingly use the sound to guide their arm choice for pup retrieval, with an increase in performance from chance to an average of ~80% on day 7.•This pairing method establishes a newly-formed sensory association using a natural maternal behavioral response, and lays a solid foundation for studies into the neurochemical and circuit mechanisms that mediate auditory associative learning in natural social contexts.