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

这项拟议的研究探索了特定动机系统和非特定动机系统在控制动物母体行为方面的相互作用。它将探索在母性行为中，下丘脑的内侧视前区(MPOA)和伏隔核-苍白球腹侧回路[NA-VP回路]之间的相互作用。先前的研究已经表明，MPOA神经回路特定地参与了母体行为的调节。相比之下，其他研究表明，NA-VP环路是非特定动机系统的一部分：该环路上的活动似乎调节着生物体对各种生物重要刺激的反应。有人提出，当NA-VP的输出由MPOA神经元驱动时，生物体的母性动机增加[如果NA-VP回路的输出由另一个特定的动机系统驱动(例如，饥饿)，那么行为反应的类型将相应地改变]。拟议的研究将采用的方法包括：(A)颅内注射药物以改变NA-VP回路内的活动；(B)将检查MPOA和NA-VP之间的通信中断对母亲行为的影响；(C)将进行神经解剖学程序，以确定关键神经回路的化学组成。据预测，从MPOA到NA-VP的连接允许婴儿刺激激活VP神经元，那些增加VP活性的治疗将促进，而那些抑制VP活性的治疗将扰乱母亲的行为。这类基础研究很重要，因为它对动机的神经生物学采取了系统水平的方法，解释了大脑如何运作来控制核心的社会动机--母性反应。重要的是，最近的功能磁共振成像研究表明，我们强调的许多在低等动物中很重要的大脑区域，在人类母亲照顾婴儿线索时也很活跃。

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.