Centering Diversity, Equity, and Inclusion in Graduate Admissions.

Many undergraduate neuroscience trainees aspire to earn a PhD. In recent years the number, demographics, and previous experiences of PhD applicants in neuroscience has changed. This has necessitated both a reconsideration of admissions processes to ensure equity for an increasingly diverse applicant pool as well as renewed efforts to expand access to the training and research experiences required for admission to graduate programs.

Early life nutritional stress affects song learning but not underlying neural circuitry in zebra finches.

Early life stress negatively impacts behavior and underlying neural circuitry across species. The present study investigated the effects of nutritional stress (NS), which increases parental foraging, on song quality in males, song preferences in females, and the size and number of cells in song and auditory regions of the zebra finch brain. We hypothesized that NS would decrease song quality in males and decrease preference for high quality song in females.

Acute exogenous corticosterone treatments have few effects on courtship and pair bonding in zebra finches.

Stress impacts social relationships. In turn, social relationships buffer the stress response in some species. Studies that have investigated the role of corticosterone (CORT) on courtship, mate choice, mating, and pairing have found mixed results.

Pairing Increases Activation of V1aR, but not OTR, in Auditory Regions of Zebra Finches: The Importance of Signal Modality in Nonapeptide-Social Behavior Relationships.

Social relationships are complex, involving the production and comprehension of signals, individual recognition, and close coordination of behavior between two or more individuals. The nonapeptides oxytocin and vasopressin are widely believed to regulate social relationships. These findings come largely from prairie voles, in which nonapeptide receptors in olfactory neural circuits drive pair bonding.

Early life stress increases testosterone and corticosterone and alters stress physiology in zebra finches.

Early life stress has enduring effects on behavior and physiology. However, the effects on hormones and stress physiology remain poorly understood. In the present study, parents of zebra finches of both sexes were exposed to an increased foraging paradigm from 3 to 33days post hatching.

Sex and pairing status explain variations in the activation of nonapeptide receptors in song and motivation regions.

The nonapeptides oxytocin and vasopressin have been implicated in a variety of social behaviors. In zebra finches, oxytocin antagonists decrease pairing in both sexes, and pairing, in turn, increases expression of both mesotocin (the avian homologue of oxytocin) and vasotocin (the avian homologue of vasopressin). Increases in mesotocin and vasotocin mRNA are correlated with the amount of directed singing by males.

Early Life Manipulations of the Nonapeptide System Alter Pair Maintenance Behaviors and Neural Activity in Adult Male Zebra Finches.

Adult zebra finches (T. guttata) form socially monogamous pair bonds characterized by proximity, vocal communication, and contact behaviors. In this experiment, we tested whether manipulations of the nonapeptide hormone arginine vasotocin (AVT, avian homolog of vasopressin) and the V1a receptor (V1aR) early in life altered species-typical pairing behavior in adult zebra finches of both sexes.

Temporary inactivation of NCM, an auditory region, increases social interaction and decreases song perception in female zebra finches.

The caudomedial nidopallium (NCM) is an important site for the storage of auditory memories, particularly song, in passerines. In zebra finches, males sing and females do not, but females use song to choose mates. The extent to which the NCM is necessary for female mate choice is not well understood.

N-methyl-D-aspartate receptor agonism and antagonism within the amygdaloid central nucleus suppresses pain affect: differential contribution of the ventrolateral periaqueductal gray.

Unlabelled: The amygdala contributes to the generation of pain affect, and the amygdaloid central nucleus (CeA) receives nociceptive input that is mediated by glutamatergic neurotransmission. The present study compared the contribution of N-methyl-d-aspartate (NMDA) receptor agonism and antagonism in the CeA to generation of the affective response of rats to an acute noxious stimulus. Vocalizations that occur following a brief tail shock (vocalization afterdischarges) are a validated rodent model of pain affect and were preferentially suppressed, in a dose-dependent manner, by bilateral injection into the CeA of NMDA (.

Same-sex partner preference in zebra finches: pairing flexibility and choice.

This study examined flexibility and choice in same-sex pair-bonding behavior in adult zebra finches (Taeniopygia guttata). Zebra finches form life-long monogamous relationships and extra pair behavior is very low, making them an ideal species in which to study same-sex pairing. We examined same-sex behaviors using both semi-naturalistic choice paradigms and skewed sex ratios.

Effects of acute corticosterone treatment on partner preferences in male and female zebra finches (Taeniopygia guttata).

Stress alters physiology and behavior across species. Most research on the effects of stress on behavior uses chronic stressors, and most are correlational. The effects of acute stressors on physiology and behavior have been mixed.

The formation and maintenance of social relationships increases nonapeptide mRNA in zebra finches of both sexes.

The nonapeptides oxytocin and vasopressin are believed to be involved in affiliation across species, but converging evidence is lacking. In monogamous zebra finches, oxytocin antagonists decrease pairing. The goal of the present study was to test if this relationship is bidirectional.

Repeated toluene exposure increases c-Fos in catecholaminergic cells of the nucleus accumbens shell.

Toluene is a frequently abused solvent. Previous studies have suggested that toluene acts like other drugs of abuse, specifically on the dopaminergic system in the nucleus accumbens (NAc) and ventral tegmental area (VTA) of the mesolimbic pathway. Although changes in dopamine (DA) levels and c-Fos have been observed in both acute and repeated exposure paradigms, the extent to which c-Fos is localized to catecholaminergic cells is unknown.

DSP-4, a noradrenergic neurotoxin, produces sex-specific effects on pairing and courtship behavior in zebra finches.

Norepinephrine (NE) is involved in a variety of behaviors across vertebrate species. In songbirds, NE is involved in singing and auditory perception, fundamental components of pair formation. Mechanisms of pairing remain poorly understood in avian species.

17β-Hydroxysteroid dehydrogenase type IV, a Z-linked gene, is higher in females than in males in visual and auditory regions of developing zebra finches.

One of the most important decisions in a monogamous animal's life is the choice of a partner (partner preference), but the process by which this occurs remains poorly understood. The present study tests the hypothesis that hormones and genes play a role in sexual differentiation of partner preferences, as in the song system. We focused on a Z-linked gene, 17β-hydroxysteroid dehydrogenase type IV (HSD17B4), coding for a steroidogenic enzyme that converts estradiol (E2) into an inactive metabolite.

Behavioral effects of progesterone on pair bonding and partner preference in the female zebra finch (Taeniopygia guttata).

Progesterone is a sex steroid known to be involved in reproduction, but its role in pair relationships is not well understood. This study explored the effects of exogenous progesterone (P4) on courtship and pairing behaviors in female zebra finches (Taeniopygia guttata) in two separate experiments: the first focused on courtship and initial pair formation and the second examined the effects on pair maintenance. In these experiments, we tested the hypothesis that P4 increases pairing behaviors and consequently influences their partner preference.

The effects of estradiol on 17β-hydroxysteroid dehydrogenase type IV and androgen receptor expression in the developing zebra finch song system.

Recent work in zebra finches suggests that genes and hormones may act together to masculinize the brain. This study tested the effects of exogenous estradiol (E2) on 17β-hydroxysteroid dehydrogenase type IV (HSD17B4) and the co-localization of HSD17B4 and androgen receptor (AR) mRNA. We asked three primary questions: First, how does post-hatching E2 treatment affect HSD17B4 mRNA expression in males and females? Second, is this gene expressed in the same cells as AR.

Sex-dependent species discrimination in auditory forebrain of naturally hybridizing birds.

Pairs of individuals breed together only if they recognize each other as the same species, but the process of recognizing conspecifics can depend on flexible criteria even when species-specific signals are innate and fixed. This study examines species recognition in naturally hybridizing sister species, California and Gambel's quail (Callipepla californica and Callipepla gambelii), that have vocalizations which are not learned. Specifically, this study tests whether being raised in a vocalizing mixed-species cohort affects neural activity in the adult auditory forebrain in response to heterospecific and conspecific calls.

Sexual differentiation of the zebra finch song system: potential roles for sex chromosome genes.

Background: Recent evidence suggests that some sex differences in brain and behavior might result from direct genetic effects, and not solely the result of the organizational effects of steroid hormones. The present study examined the potential role for sex-biased gene expression during development of sexually dimorphic singing behavior and associated song nuclei in juvenile zebra finches.

Results: A microarray screen revealed more than 2400 putative genes (with a false discovery rate less than 0.

Monogamy on the fast track.

Social monogamy has evolved multiple times and is particularly common in birds. It is not well understood why some of these species are continuously and permanently paired while others occasionally 'divorce' (switch partners). Although several hypotheses have been considered, experimental tests are uncommon.

Sexually dimorphic SCAMP1 expression in the forebrain motor pathway for song production of juvenile zebra finches.

Mechanisms regulating sexual differentiation of the zebra finch song system are not well understood. The present study was designed to more fully characterize secretory carrier membrane protein 1 (SCAMP1), which was identified in a cDNA microarray screen as showing increased expression in the forebrains of developing male compared with female zebra finches. We completed the sequence of the open reading frame and used in situ hybridization to compare mRNA in song control regions of juvenile (25-day-old) individuals.

Immediate early gene (ZENK) responses to song in juvenile female and male zebra finches: effects of rearing environment.

Accurate song perception is likely to be as important for female songbirds as it is for male songbirds. Male zebra finches (Taeniopygia guttata) show differential ZENK expression to conspecific and heterospecific songs by day 30 posthatch in auditory perceptual brain regions such as the caudomedial nidopallium (NCM) and the caudomedial mesopallium (CMM). The current study examined ZENK expression in response to songs of different qualities at day 45 posthatch in both sexes.

The role of sex steroids in courtship, pairing and pairing behaviors in the socially monogamous zebra finch.

The purpose of this study was to test whether sex steroid actions are necessary for courtship and pairing in socially monogamous birds. We examined the effects of an aromatase inhibitor, 1,4,6-androstatriene-3,17-dione (ATD), combined with an anti-androgen, flutamide (F), on the behavior and pairing status of initially unpaired male and female zebra finches (Taeniopygia guttata). In the first experiment, 24 adult males were implanted with either a combination of ATD and flutamide or empty implants.

Sex differences in juvenile rhesus macaque (Macaca mulatta) agonistic screams: life history differences and effects of prenatal androgens.

This study investigated sex differences in juvenile rhesus macaque (Macaca mulatta) vocal behavior during agonistic contexts, and the effects of prenatal androgens on these differences. A total of 59 subjects (5-8 per treatment group) received exogenous androgen (testosterone enanthate), an anti-androgen (flutamide) or vehicle injections (DMSO) for 30 or 35 days during the second (early) or third (late) trimester of pregnancy. An additional 19 unmanipulated controls were included in the analysis.

Cannabinoid inhibition improves memory in food-storing birds, but with a cost.

Food-storing birds demonstrate remarkable memory ability in recalling the locations of thousands of hidden food caches. Although this behaviour requires the hippocampus, its synaptic mechanisms are not understood. Here we show the effects of cannabinoid receptor (CB1-R) blockade on spatial memory in food-storing black-capped chickadees (Poecile atricapilla).