Details

Autor(en) / Beteiligte

• Schiavo, Jennifer K

Titel

Innate and Plastic Mechanisms in Rodent Auditory Cortex for Maternal Behavior

Ort / Verlag

ProQuest Dissertations & Theses

Erscheinungsjahr

2020

Quelle

ProQuest Dissertations & Theses A&I

Beschreibungen/Notizen

• To what extent are our behaviors driven by ‘nature’ (innate or hardwired processes) or ‘nurture’ (learned from experience)? For my thesis work, I studied how innate and learned processes interact for the onset of maternal behavior in mice. Specifically, we took advantage of an auditory-driven maternal behavior, retrieval of isolated pups, to examine the extent to which auditory cortex is intrinsically tuned to vocal features prior to parental experience, and what neuroplastic mechanisms underlie auditory learning for the recognition of pup vocalizations. Mouse mothers retrieve pups isolated from the nest based on ultrasonic distress calls emitted from lost pups. In contrast, pup-naive virgins do not recognize the meaning of pup distress calls, but retrieve isolated pups to the nest following cohousing with a mother and litter. We found that the onset of maternal behavior in virgins resulted from experience-dependent plasticity that built on an intrinsic sensitivity to the most common pup call repetition rate. In maternal females, calls with inter-syllable intervals (ISIs) from 75 to 375 ms elicited pup retrieval, and cortical responses generalized across these ISIs. In contrast, pup-naive virgins were behaviorally sensitive only to the most common (‘prototypical’) ISIs, and excitatory neurons were narrowly tuned to prototypical pup calls. Inhibitory and excitatory neuronal and synaptic tuning were initially mismatched in naive cortex, with untuned inhibition and overly-narrow excitation. During cohousing, excitatory neurons broadened their tuning to represent a wider range of ISIs, while interneurons sharpened their tuning to form a perceptual boundary. We presented synthetic calls during cohousing and observed that neurobehavioral responses adjusted to match these statistics, a process requiring auditory cortical activity and the hypothalamic oxytocin system. Neuroplastic mechanisms therefore build on an intrinsic sensitivity in mouse auditory cortex, enabling rapid plasticity for reliable parenting behavior.