Role of Rodent Vocalizations in Cocaine-Induced Maternal Neglect

A greater incidence of maternal neglect, problems with mother-infant bonding, child abuse, and placement in foster homes has been correlated with maternal cocaine use during pregnancy compared to mothers with no gestational cocaine use. Infants exposed to cocaine during pregnancy show many signs, particularly early in the postnatal period, of poor state control including: irregular crying behavior, and extreme state liability. To date little evidence has been published of how cocaine decreases both maternal perception of infant care needs and infant elicitation of maternal response. Using an animal model of cocaine-induced maternal neglect the aim of this dissertation is to: 1) record and quantify differences following prenatal cocaine exposure in infant rat vocalizations, a known stimulus of rodent maternal behavior; 2) test whether gestational cocaine treatment decreases maternal preference-like behavior for recorded vocalizations from prenatal cocaine-exposed infant rats; and 3) determine if any identified cocaine-induced decreases in maternal proximity preference for infant rat vocalization recordings correlate with maternal neurobiological differences in oxytocin, cFos and FosB protein expression. The data presented in this dissertation demonstrate that cocaine-treatment during gestation alters infant rat vocalization characteristics, decreases maternal preference for prenatal cocaine-exposed infant rat vocalization recordings, and that oxytocin expression in the medial preoptic area is decreased in cocaine-treated rat mothers that choose to spend less time in close proximity to recordings of prenatal cocaine-exposed infant rat vocalizations. Ultimately these data provide justification for continued work to explore the separate and interactive factors influencing maternal behavior and within this theoretical framework to drive development of both behavioral and pharmacotherapeutic interventions for the treatment of maternal neglect.Doctor of Philosoph