Interactions between medial preoptic area, nucleus accumbens, and ventral pallidum in the control of mammalian maternal behavior

Boston College, Chestnut Hill MA

Investigators

Abstract

The proposed research explores the interaction between specific and nonspecific motivational systems in the control of maternal behavior in animals. It will explore the interactions between the medial preoptic area (MPOA) of the hypothalamus and the nucleus accumbens-ventral pallidal circuit [NA-VP circuit] in maternal behavior. Previous research has shown the specific involvement of MPOA neural circuits in the regulation of maternal behavior. In contrast, other research has indicated that the NA-VP circuit is part of a nonspecific motivational system: activity across this circuit appears to regulate an organism's responsiveness to a wide variety of biologically significant stimuli. It is proposed that when the output of the NA-VP is driven by MPOA neurons, the organism's maternal motivation is increased [if output of the NA-VP circuit were to be driven by another specific motivational system (hunger, for example), then the type of behavioral reactivity would change accordingly]. The methods that will be employed in the proposed study include: (a) intracranial injections of drugs to alter activity within the NA-VP circuit; (b) the effects of disrupting communication between MPOA and NA-VP on maternal behavior will be examined; (c) neuroanatomical procedures to define the chemical makeup of the critical neural circuits will be performed. It is predicted that connections from the MPOA to NA-VP allow infant stimuli to activate VP neurons, and that those treatments which increase VP activity will facilitate, and those that depress VP activity will disrupt, maternal behavior. This type of basic research is important because it takes a systems level approach to the neurobiology of motivation, explaning how the brain operates to control a core social motivation - maternal responsiveness. Importantly, recent fMRI work indicates that many of the brain regions we emphasize that are important in lower animals are also active in human mothers attending to infant cues.