Biology Biology Monday Seminar "Lactation hormones, brains, and parenting behavior in birds and mammals"

Dr. Kristina Smiley

Post-doctoral Researcher, UMass Amherst

Parental care is critical for offspring survival across many diverse taxa. The transition into parenting involves extraordinary coordination of multiple neural and hormonal systems, as well as other physiological adaptations that occur before and after birth to support the onset of offspring-directed behavior. My research has focused on how prolactin, a hormone most well-known for its role in lactation, promotes parental behavior in both birds and mammals. I will present evidence that shows prolactin is necessary for the onset of parenting behaviors in both male and female songbirds, and that prolactin-receptors are found in many regions throughout the avian brain that may support parenting, such as the medial preoptic area of the hypothalamus. To follow up these findings, I found that a specific population of prolactin-responsive cells in the medial preoptic area in male mice is critical for paternal behavior. Together, these results suggest that prolactin has a conserved role in promoting parental behaviors, likely acting on conserved neural circuitry between rodents and birds. In addition to the neuroendocrine changes that occur, sensory cues unique to dependent offspring are also critical for eliciting parental behavior. How these cues are encoded by the brain to elicit behavioral responses, and whether hormones affect the perception of sensory information from offspring is not well understood. My current work is examining the neural responses to offspring auditory cues (begging calls) in biparental songbirds, with the prediction that parents will show enhanced responsiveness to begging calls, relative to non-parents, and these responses will become more selective over the developmental period. Finally, I will present some future directions of my reserch which aims to investigate: 1) how parental hormones affect the perception of sensory information from offspring, 2) how exposure to offspring sensory cues can alter hormonal state in the parents, and 3) the neural circuitry underlying these processes.