دانلود رایگان مقاله انگلیسی عصب شناسی، غدد درون ریز و رفتار - الزویر 2018

Abstract

The experimental study of the physiological mechanisms of animal behavior, which began in the 1800s, has dual origins. Research on neural mechanisms, now referred to as behavioral neurobiology, neuroethology, or behavioral neuroscience, has its roots in comparative neuroanatomy, comparative physiology, and physiological psychology. Research on hormonal mechanisms, now known as behavioral neuroendocrinology, arose from endocrinology in addition to many other fields. With the realization that the nervous and endocrine systems are functionally connected, there has been increased integration within the field. Connections with several newer branches of science, such as molecular biology, have been established as well.

The Molecular Era

Methodologies arising from molecular biology are now revolutionizing our understanding of the role of specific hormones and their receptors in behavior (Pfaff and Joels, 2017). For example, research in “knock-out” mice made mutant for the gene for oxytocin, the oxytocin receptor, or the vasopressin (V1a) receptor suggests that both oxytocin and vasopressin are important for selective, social recognition learning (Young and Hammock, 2007). However, it is interesting that mice with these genetic deficits are not asocial, can still give birth, and remain capable of maternal behavior. Taken together, and in the context of studies of pair bond formation, these findings suggest that in mammals, both oxytocin and vasopressin are necessary for the development of selective social interactions. These molecules, along with many others, work as components of a highly integrated and often sexually dimorphic neural circuitry for social behavior. Molecular methods have also been used to demonstrate that differences in the expression of the genes for neuropeptide receptor are correlated with species- and individual-differences in patterns of sociality. By over-expressing certain genes, it is possible to create animals capable of showing behavioral patterns that are not usually seen in their species. For example, increasing availability of the V1a receptor in specific brain regions produces males capable of forming pair bonds, even in species, such as montane voles, for which this is atypical. Studies of mice that lack the gene for specific steroid receptors are also providing a new understanding of the behavioral effects of compounds such as estrogen, progesterone, and androgen. This research is complicated by interactions among different hormones and the presence of various subtypes of steroid receptors. However, such work has important translational implications because of the many medical manipulations of hormones, including widely used hormone replacement therapies and contraceptives.