Maternal care, including by non-biological parents, is important for offspring survival1–8. Oxytocin1,2,9–15, which is released by the hypothalamic paraventricular nucleus (PVN), is a critical maternal hormone. In mice, oxytocin enables neuroplasticity in the auditory cortex for maternal recognition of pup distress15. However, it is unclear how initial parental experience promotes hypothalamic signalling and cortical plasticity for reliable maternal care. Here we continuously monitored the behaviour of female virgin mice co-housed with an experienced mother and litter. This documentary approach was synchronized with neural recordings from the virgin PVN, including oxytocin neurons. These cells were activated as virgins were enlisted in maternal care by experienced mothers, who shepherded virgins into the nest and demonstrated pup retrieval. Virgins visually observed maternal retrieval, which activated PVN oxytocin neurons and promoted alloparenting. Thus rodents can acquire maternal behaviour by social transmission, providing a mechanism for adapting the brains of adult caregivers to infant needs via endogenous oxytocin.

Purpose: The primary purpose of this study was to describe the frequency and types of speech disfluencies that are produced by bilingual Spanish-English (SE) speaking children who do not stutter. The secondary purpose was to determine whether their disfluent speech is mediated by language dominance and/or language produced. Method: Spanish and English narratives (a retell and a tell in each language) were elicited and analyzed relative to the frequency and types of speech disfluencies produced. These data were compared with the monolingual English-speaking guidelines for differential diagnosis of stuttering.Results: The mean frequency of stuttering-like speech behaviors in the bilingual SE participants ranged from 3% to 22%, exceeding the monolingual English standard of 3 per 100 words. There was no significant frequency difference in stuttering-like or non-stuttering-like speech disfluency produced relative to the child's language dominance. There was a significant difference relative to the language the child was speaking; all children produced significantly more stutteringlike speech disfluencies in Spanish than in English. Conclusion: Results demonstrate that the disfluent speech of bilingual SE children should be carefully considered relative to the complex nature of bilingualism.

Maternal care is profoundly important for mammalian survival, and maternal behaviors can also be expressed by non-biological parents after experience with infants. One critical molecular signal for maternal behavior is oxytocin, a hormone released in the brain by hypothalamic paraventricular nucleus (PVN). Oxytocin enables plasticity within the auditory cortex, a necessary step for responding to infant vocalizations. To determine how this change occurs during natural experience, we continuously monitored homecage behavior of female virgin mice co-housed for days with an experienced mother and litter, synchronized with in vivo recordings from virgin PVN cells, including from identified oxytocin neurons. Mothers engaged virgins in maternal care by ensuring that virgins were in the nest, and demonstrated maternal behavior in self-generated pup retrieval episodes. These social interactions activated virgin PVN and gated behaviorally-relevant cortical plasticity for pup distress calls. Thus rodent maternal behavior can be learned by social transmission, and our results describe a mechanism for adapting the brains of adult caregivers to infant needs via endogenous oxytocin. One Sentence Summary:Mother mice help co-housed virgins become maternal by enacting specific behaviors that activate virgin oxytocin neurons.Main Text: Social interactions, such as pair bond formation and child rearing, are fundamental aspects of animal and human behavior (1-4). Parental care is especially important in mammals, and new parents must rapidly and reliably express a number of behaviors required for survival of offspring. Some parental behavior is therefore believed to be at least in part innate and hard-wired, or gated by neurochemical changes after mating. However, maternal behavior can also be acquired from experience. In humans and other primates, individuals other than the biological parents can learn to successfully care for children after instruction or observation of experienced caretakers and infants (1-8). It is unclear how expression of such alloparenting behaviors in rodents or other species can also be learned from experience, and if so, what mechanisms of neuromodulation and plasticity underlie learning of maternal behaviors.One of the most important molecular modulators of neural circuit function for social interactions and maternal physiology is the evolutionarily-ancient peptide hormone oxytocin (1,2, 9,10). In mammals, oxytocin is released from the hypothalamus and is critical for childbirth and lactation (10,11). Oxytocin also acts in the brain where it is believed to increase the salience of social information, enhancing pair bonding and maternal behavior (1,9,(12)(13)(14)(15), and enabling onset of alloparenting in mice. Specifically, pup-naïve virgin female mice initially ignore neonates and cues related to infant need, e.g., ultrasonic distress calls emitted by pups isolated from the nest (15). However, after several days of co-housing with experienced mothers ('dams') and litters, most virgin females become mate...

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