Familiarity and Mate Preference Assessment with the Partner Preference Test

In contrast to traditional laboratory animals, prairie voles form socially monogamous partnerships in the wild and exhibit lasting social preferences for familiar individuals-both mates and same-sex peers-in the laboratory. Decades of research into the mechanisms supporting pair bonding behavior have made prairie voles an important model organism for the study of social relationships. The partner preference test is a laboratory test of familiarity preference that takes place over an extended interval (typically 3 hr), during which test subjects can directly interact with conspecifics and often engage in resting side-by-side contact (i.e., huddling). The use of this test has enabled study of the neural pathways and mechanisms involved in promoting or impairing relationship formation. The tendency to form partner preferences is also used as a behavioral indicator of the effects of early life experiences and environmental exposures. While this test was developed to assess the extent of social preference for mates in prairie voles, it has been adapted for use in other social contexts and in multiple other species. This article provides instructions for conducting the classic partner preference test, as well as variations including same-sex peer partner preference tests. The effects of several protocol variations are examined, including duration of cohousing, separation interval, use of tethers versus barriers, linear versus branched apparatus configuration, and duration of the test. The roles of social variables including sex of the focal individual, sex of conspecifics, reproductive state, and use of the test in other species are then considered. Finally, sample data are provided along with discussion of scoring and statistical analysis of partner preference tests

Identifying Compliance Issues in the Community Health Care Clinic Environment

This study explored the high number of failed appointments and follow-up appointments at a community health care children’s clinic. A thirty-seven item questionnaire was randomly given to 112 participants seeking health care at the clinic on a random basis. Based on literature reviews, five hypothesis were generated to examine reasons for failing to keep appointments for children: 1. Communication difficulties between healthcare personnel and parents regarding patient comprehension of instructions and bottle directions were anticipated. 2. Patient/physician/clinic relationships were expected to influence patient compliance. The need for more reminder calls for appointments was anticipated to be a factor in patient compliance also. 3. Influence from other family members or subjective norms was anticipated to influence patient follow-up and medication compliance. 4. Socioeconomic conditions were anticipated to have a bearing on whether some parents were able to complete medical treatment plans. 5. The healthcare beliefs and lack of awareness of preven tative medicine was believed to be a barrier to follow-up appointments and well-child appointments. Findings indicated that patients did have difficulties with instructions and bottle directions. Patients also expressed a need for reminder calls, admitted to being influenced by other family members, and indicated that their financial resources for medical care were limited. Nearly one-half of the respondents stated that they did not know what the term “preventative medicine” meant. These findings indicate that new tools for communicating medical treatment and increasing healthcare awareness are needed

Frank Beach award winner: Neuroendocrinology of Group Living

Why do members of some species live in groups while others are solitary? Group living (sociality) has often been studied from an evolutionary perspective, but less is known about the neurobiology of affiliation outside the realms of mating and parenting. Colonial species offer a valuable opportunity to study nonsexual affiliative behavior between adult peers. Meadow voles (Microtus pennsylvanicus) display environmentally induced variation in social behavior, maintaining exclusive territories in summer months, but living in social groups in winter. Research on peer relationships in female meadow voles demonstrates that these selective preferences are mediated differently than mate relationships in socially monogamous prairie voles, but are also impacted by oxytocin and HPA axis signaling. This review addresses day-length dependent variation in physiology and behavior, and presents the current understanding of the mechanisms supporting selective social relationships in meadow voles, with connections to lessons from other species

Neurobiology of Stress

The neurobiology of stress and the neurobiology of social behavior are deeply intertwined. The social environment interacts with stress on almost every front: social interactions can be potent stressors; they can buffer the response to an external stressor; and social behavior often changes in response to stressful life experience. This review explores mechanistic and behavioral links between stress, anxiety, resilience, and social behavior in rodents, with particular attention to different social contexts. We consider variation between several different rodent species and make connections to research on humans and nonhuman primates

Sex Bias in Neuroscience and Biomedical Research

Female mammals have long been neglected in biomedical research. The NIH mandated enrollment of women in human clinical trials in 1993, but no similar initiatives exist to foster research on female animals. We reviewed sex bias in research on mammals in 10 biological fields for 2009 and their historical precedents. Male bias was evident in 8 disciplines and most prominent in neuroscience, with single-sex studies of male animals outnumbering those of females 5.5 to 1. In the past half-century, male bias in non-human studies has increased while declining in human studies. Studies of both sexes frequently fail to analyze results by sex. Underrepresentation of females in animal models of disease is also commonplace, and our understanding of female biology is compromised by these deficiencies. The majority of articles in several journals are conducted on rats and mice to the exclusion of other useful animal models. The belief that non-human female mammals are intrinsically more variable than males and too troublesome for routine inclusion in research protocols is without foundation. We recommend that when only one sex is studied, this should be indicated in article titles, and that funding agencies favor proposals that investigate both sexes and analyze data by sex

Selectivity and Sociality: Aggression and Affiliation Shape Vole Social Relationships

The formation of selective social relationships is not a requirement of group living; sociality can be supported by motivation for social interaction in the absence of preferences for specific individuals, and by tolerance in place of social motivation. For species that form selective social relationships, these can be maintained by preference for familiar partners, as well as by avoidance of or aggression toward individuals outside of the social bond. In this review, we explore the roles that aggression, motivation, and tolerance play in the maintenance of selective affiliation. We focus on prairie voles (Microtus ochrogaster) and meadow voles (Microtus pennsylvanicus) as rodent species that both exhibit the unusual tendency to form selective social relationships, but differ with regard to mating system. These species provide an opportunity to investigate the mechanisms that underlie social relationships, and to compare mechanisms supporting pair bonds with mates and same-sex peer relationships. We then relate this to the role of aggression in group composition in a comparative context

Life in Groups: The Roles of Oxytocin in Mammalian Sociality

In recent decades, scientific understanding of the many roles of oxytocin (OT) in social behavior has advanced tremendously. The focus of this research has been on maternal attachments and reproductive pair-bonds, and much less is known about the substrates of sociality outside of reproductive contexts. It is now apparent that OT influences many aspects of social behavior including recognition, trust, empathy, and other components of the behavioral repertoire of social species. This review provides a comparative perspective on the contributions of OT to life in mammalian social groups. We provide background on the functions of OT in maternal attachments and the early social environment, and give an overview of the role of OT circuitry in support of different mating systems. We then introduce peer relationships in group-living rodents as a means for studying the importance of OT in non-reproductive affiliative behaviors. We review species differences in oxytocin receptor (OTR) distributions in solitary and group-living species of South American tuco-tucos and in African mole-rats, as well as singing mice. We discuss variation in OTR levels with seasonal changes in social behavior in female meadow voles, and the effects of OT manipulations on peer huddling behavior. Finally, we discuss avenues of promise for future investigation, and relate current findings to research in humans and non-human primates. There is growing evidence that OT is involved in social selectivity, including increases in aggression toward social outgroups and decreased huddling with unfamiliar individuals, which may support existing social structures or relationships at the expense of others. OT’s effects reach beyond maternal attachment and pair bonds to play a role in affiliative behavior underlying “friendships”, organization of broad social structures, and maintenance of established social relationships with individuals or groups

Adaptive Significance of Natural Variations in Maternal Care in Rats: A Translational Perspective

A wealth of data from the last fifty years documents the potency of early life experiences including maternal care on developing offspring. A majority of this research has focused on the developing stress axis and stress-sensitive behaviors in hopes of identifying factors impacting resilience and risk-sensitivity. The power of early life experience to shape later development is profound and has the potential to increase fitness of individuals for their environments. Current findings in a rat maternal care paradigm highlight the complex and dynamic relation between early experiences and a variety of outcomes. In this review we propose adaptive hypotheses for alternate maternal strategies and resulting offspring phenotypes, and ways to distinguish between these hypotheses. We also provide evidence underscoring the critical role of context in interpreting the adaptive significance of early experiences. If our goal is to identify risk-factors relevant to humans, we must better explore the role of the social and physical environment in our basic animal models

The Role of Dopamine Signaling in Prairie Vole Peer Relationships

Dopamine signaling mediates the formation of some types of social relationships, including reproductive pair bonds in the socially monogamous prairie vole (Microtus ochrogaster). In addition to these pair bonds with mates, prairie voles demonstrate selective preferences for familiar same-sex peers. The dependence of peer relationships on dopamine signaling has not been tested, and the mechanisms supporting these relationships may differ from those underlying pair bonds. We examined the effects of pharmacological manipulations of dopamine signaling on peer partner preference and socially conditioned place preference in female prairie voles. Haloperidol blockade of dopamine receptors at multiple doses did not alter selective preferences for familiar same-sex partners, suggesting that dopamine neurotransmission is not necessary for the formation of prairie vole peer relationships, unlike mate relationships. Dopamine receptor agonist apomorphine facilitated peer partner preferences under conditions normally insufficient for partner preference formation; however, in the absence of effects from blockade, it is difficult to distinguish between a role for dopamine in partner preference formation and the generally rewarding properties of a dopamine agonist. Prairie voles exhibited socially conditioned place preferences for new but not long-term same-sex peers, and these preferences were not blocked by haloperidol. These results suggest that prairie vole peer relationships are less dependent on dopamine signaling than pair bonds, while still being rewarding. The data support distinct roles of dopamine and motivation in prairie vole peer relationships relative to mate relationships, suggesting that reproductive bonds are mediated differently from non-reproductive ones