Publications by authors named "Karen Bales"

There is a critical need to generate age- and sex-specific survival curves to characterize chronological aging consistently across nonhuman primates (NHP) used in biomedical research. Sex-specific Kaplan-Meier survival curves were computed in 12 translational aging models: baboon, bonnet macaque, chimpanzee, common marmoset, coppery titi monkey, cotton-top tamarin, cynomolgus macaque, Japanese macaque, pigtail macaque, rhesus macaque, squirrel monkey, and vervet/African green. After employing strict inclusion criteria, primary results are based on 12,269 NHPs that survived to adulthood and died of natural/health-related causes.

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Oxytocin receptor (Oxtr) signaling influences complex social behaviors in diverse species, including social monogamy in prairie voles. How Oxtr regulates specific components of social attachment behaviors and the neural mechanisms mediating them remains unknown. Here, we examine prairie voles lacking Oxtr and demonstrate that pair bonding comprises distinct behavioral modules: the preference for a bonded partner, and the rejection of novel potential mates.

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Article Synopsis
  • There is a significant need to create age- and sex-specific survival curves for nonhuman primates (NHP) in biomedical research to better understand aging.
  • A study analyzed data from over 110,000 captive NHP to generate survival curves for various species, reporting meaningful differences in lifespans and health based on sex and species type.
  • Results indicated that male NHP, particularly among certain African and Asian species, had reduced survival rates, and median lifespans were often lower than what was previously documented, suggesting these analyses may more accurately reflect healthspan rather than just lifespan.
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The coppery titi monkey (Plecturocebus cupreus) is an emerging nonhuman primate model system for behavioral and neurobiological research. At the same time, the almost entire absence of genomic resources for the species has hampered insights into the genetic underpinnings of the phenotypic traits of interest. To facilitate future genotype-to-phenotype studies, we here present a high-quality, fully annotated de novo genome assembly for the species with chromosome-length scaffolds spanning the autosomes and chromosome X (scaffold N50 = 130.

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Primates live in a variety of social groupings and vary in the expression of species-typical behaviors depending upon social conditions. Coppery titi monkeys () are pair-bonding, territorial primates often used to study neurobiology and social behavior in captivity at the California National Primate Research Center (CNPRC). At the center, titi monkeys are housed in cages of standardized size.

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Social bonds influence physiology and behavior, which can shape how individuals respond to physical and affective challenges. Coppery titi monkey (Plecturocebus cupreus) offspring form selective bonds with their fathers, making them ideal for investigating how father-daughter bonds influence juveniles' responses to oxytocin (OT) and arginine-vasopressin (AVP) manipulations. We quantified the expression of father-daughter bond-related behaviors in females (n = 10) and gave acute intranasal treatments of saline, low/medium/high OT, low/high AVP, or an OT receptor antagonist (OTA) to subjects prior to a parent preference test.

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Oxytocin: A developmental journey.

Compr Psychoneuroendocrinol

November 2023

The neuropeptide hormone oxytocin is involved in many processes in our bodies, linking our social lives to our internal states. I started out my career studying primate families, an interest that expanded into the role of oxytocin in family-oriented behaviors such as pair bonding and parenting in prairie voles, humans, and other primates. Starting as a post-doc with Dr.

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Hormonal contraception is an effective, reversible tool for managing birth rates in humans and nonhuman animals alike. However, manipulating reproductive hormones has behavioral consequences that can impact social and sexual behavior between conspecifics. First, we studied 18 pairs of nonreproductive titi monkeys () to test the efficacy of a novel method of hormonal contraception (deslorelin acetate implants) on reproductive hormone cycling in females and found significant reductions in urinary estrogens and progestagens among treated females compared to untreated controls.

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Strong social bonds are critical to human health; however, the mechanisms by which social bonds are formed and maintained are still being elucidated. The neurohormones oxytocin (OT) and vasopressin (AVP) are considered likely candidates. Primate females, both human and nonhuman, remain understudied populations.

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Social interactions regulate our behavior and physiology, and strong social bonds can buffer us from stress. Coppery titi monkeys (Plecturocebus cupreus) are socially monogamous South American monkeys that display strong social bonds. Infants form selective bonds with their fathers, making them ideal for studying father-daughter bonds.

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Increasing evidence suggests that intact social bonds are protective against age-related morbidity, while bond disruption and social isolation increase the risk for multiple age-related diseases. Social attachments, the enduring, selective bonds formed between individuals, are thus essential to human health. Socially monogamous species like the prairie vole (M.

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Mammalian infants depend on parental care for survival, with numerous consequences for their behavioral development. We investigated the epigenetic and neurodevelopmental mechanisms mediating the impact of early biparental care on development of alloparenting behavior, or caring for offspring that are not one's own. We find that receiving high parental care early in life leads to slower epigenetic aging of both sexes and widespread male-specific differential expression of genes related to synaptic transmission and autism in the nucleus accumbens.

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Pair bonding builds on preexisting dopamine connectivity to help form and maintain the bond. The involvement of dopaminergic pathways in pair bonding has stimulated research linking pair bonds to other dopamine-dependent processes, like addiction and social cognition (Burkett & Young, 2012; Yetnikoff, Lavezzi, Reichard, & Zahm, 2014). Less studied is the relationship of pair bonding to non-social cognitive processes.

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This article describes survivorship and explores factors affecting mortality risks in a captive colony of coppery titi monkeys (Plecturocebus cupreus) housed at the California National Primate Research Center (CNPRC), at UC Davis, in Davis, CA. We analyzed data collected on individuals since the colony's creation in the 1960s, with a sample of 600 animals with partially complete information (date of birth, age at death, body mass, parental lineage). We used three methods: (1) Kaplan-Meier regressions followed by a log-rank test to compare survival in male and female titi monkeys, (2) a breakpoint analysis to identify shifts in the survival curves, and (3) Cox regressions to test the effect of body mass change, parental pair tenure, and parental age on mortality risk.

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Parenting induces many neurological and behavioral changes that enable parents to rear offspring. Vasopressin plays an important role in this process via its effects on cognition, affect, and neuroplasticity, and in some cases, via interactions with decreased parental androgens. Thus far, the role of these hormones has been primarily studied in rodents.

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Behavioral compatibility plays a critical role in shaping how potential mates interact with and evaluate each other and whether they choose to pursue a relationship. Compatibility is especially important for mate choice and relationship quality in pair-bonding species that form long-term attachments between mates. Although this process has been studied in humans and birds, relatively few studies have investigated it in non-human primates.

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Jealousy is a social emotion that manifests as behavioral reactions from an individual toward a threat to a valuable relationship. Monogamous species exhibit jealousy-type behaviors as an adaptive response to preserve the relationship. Jealousy is also a complex, negatively-valenced emotion which may include fear of loss, anxiety, suspiciousness, and anger.

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The concept of "social homeostasis", introduced by Matthews and Tye in 2019, has provided a framework with which to consider our changing individual needs for social interaction, and the neurobiology underlying this system. This model was conceived as including detector systems, a control center with a setpoint, and effectors which allow us to seek out or avoid additional social contact. In this article, we review and theorize about the many different factors that might contribute to the setpoint of a person or animal, including individual, social, cultural, and other environmental factors.

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Pair bonding in humans and other socially monogamous species can have positive effects on health and well-being. These attachments also come with the potential for challenges such as separation, jealousy, or grief. Much of the work on the neurobiology of pair bonding in non-human primates has been carried out in coppery titi monkeys (Plecturocebus cupreus), a monogamous South American monkey, although these studies have been primarily in males.

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Prairie voles are among a small group of mammals that display long-term social attachment between mating partners. Many pharmacological studies show that signaling via the oxytocin receptor (Oxtr) is critical for the display of social monogamy in these animals. We used CRISPR mutagenesis to generate three different Oxtr-null mutant prairie vole lines.

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Some paired primates use complex, coordinated vocal signals to communicate within and between family groups. The information encoded within those signals is not well understood, nor is the intricacy of individuals' behavioral and physiological responses to these signals. Considering the conspicuous nature of these vocal signals, it is a priority to better understand paired primates' responses to conspecific calls.

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How should we characterize the affective lives of non-human animals? There is a large body of work studying affective processes in non-human animals, yet this work is frequently overlooked. Ideas about the affective lives of animals have varied across culture and time and are reflected in literature, theology, and philosophy. Our contemporary ideas about animal affect are philosophically important within the discipline of , and these ideas have consequences in several domains, including animal husbandry, conservation, and human and veterinary medicine.

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Long-term relationships are essential for the psychological wellbeing of humans and many animals. Positive emotions and affective experiences (e.g.

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Romantic first impressions seem to linger, but why? Few studies have investigated how romantic desire during initial interactions predicts later relational outcomes (e.g., later romantic interest, contact attempts) using a design that can tease apart different possible mechanisms (e.

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Selective adult social attachments, or 'pair bonds', represent central relationships for individuals in a number of social species, including humans. Loss of a pair mate has emotional consequences that may or may not diminish over time, and that often translate into impaired psychological and physical health. In this paper, we review the literature on the neuroendocrine mechanisms for the emotional consequences of partner loss, with a special focus on hypothesized interactions between oxytocin, corticotropin-releasing hormone and the opioid system.

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