Biology subjects

Marlin, B. J.

Publications and source records attributed to Marlin, B. J..

5 recordsLinked to original sources

bioRxiv2026

Maternal experience alters brain-wide representation of infant cries

One SentenceMaternal experience fundamentally reorganizes infant cue processing across the entire brain into a more efficient and specialized caregiving state. Pup calls signal the presence of a mouse infant in need of care (Bernd Haack et al., 1983; Ehret, 2005). Previous work demonstrated that experience-dependent plasticity within the left primary auditory cortex is oxytocin-facilitated and enhances neural and behavioral responses to these distress vocalizations (Marlin et al., 2015). However, whether maternal experience reshapes pup call processing beyond auditory regions remains unknown. Here, we show that both innate and learned maternal experience shape pup call-evoked behavior and brain-wide neural responses. Combining behavioral assays, whole-brain activity mapping, and oxytocinergic projection analyses, we find that pup calls recruit distinct large-scale neural networks in naive virgins, experienced virgins, and mothers. With more maternal experience we observe a distributed pup call response network that is sparser yet more strongly coactivated, consistent with a more efficient and specialized neural representation of infant cues. We identified an oxytocin-dense circuit that shows an experience-dependent pup call response pattern. Therefore, we propose that experience-dependent refinement of the brain-wide response to pup calls is facilitated by oxytocin. Taken together, our findings reveal that maternal experience refines brain-wide sensory processing to support adaptive caregiving behavior.

neuroscience↗

bioRxiv2025

Early postpartum development of pup urine preference in mothers

The transition to motherhood involves profound physiological and neural changes, including adaptations in the sensory systems that support infant care.1,2 While the olfactory system plays a critical role in guiding maternal behaviors such as pup retrieval and nesting,3,4 how olfactory processing itself is reshaped during motherhood remains poorly understood. Here, we show that first-time mothers develop a selective preference for pup urine following parturition and early postpartum care, a preference not observed for other social or neutral odors. Using odor preference assays combined with liquid and gas chromatography-mass spectrometry, we identify specific volatile compounds in pup urine that may contribute to this maternal attraction. Disruption of olfactory input or restriction of contact chemosensation abolished the preference, indicating that both volatile and non-volatile sensory modalities contribute, likely through combined input from the main olfactory epithelium (MOE) and vomeronasal organ (VNO).5,6 Notably, this preference is absent in late-pregnant females, in mothers separated from pups at birth, and in virgins cohoused with pups or exposed to pup urine-highlighting that pup urine preference depends on the convergence of internal hormonal signals and external chemosensory cues.7,8 These findings reveal a previously unrecognized specificity in maternal olfactory behavior and provide insight into how motherhood modulates the sense of smell to support offspring recognition and care. In BriefMaternal pup urine preference depends on both hormonal changes and chemosensory cues associated with motherhood. HighlightsO_LIPup urine specifically attracts postpartum mothers but not virgin females C_LIO_LIPup urine contains distinct volatile and non-volatile metabolites C_LIO_LIPup urine preference requires both pup experience and the hormonal priming of motherhood C_LI

neuroscience↗

bioRxiv2023

Opposing, spatially-determined epigenetic forces impose restrictions on stochastic olfactory receptor choice

Olfactory receptor (OR) choice represents an example of genetically hardwired stochasticity, where every olfactory neuron expresses one out of [~]2000 OR alleles in a probabilistic, yet stereotypic fashion. Here, we propose that topographic restrictions in OR expression are established in neuronal progenitors by two opposing forces: polygenic transcription and genomic silencing, both of which are influenced by dorsoventral gradients of transcription factors NFIA, B, and X. Polygenic transcription of OR genes may define spatially constrained OR repertoires, among which one OR allele is selected for singular expression later in development. Heterochromatin assembly and genomic compartmentalization of OR alleles also vary across the axes of the olfactory epithelium and may preferentially eliminate ectopically expressed ORs with more dorsal expression destinations from this "privileged" repertoire. Our experiments identify early transcription as a potential "epigenetic" contributor to future developmental patterning and reveal how two spatially responsive probabilistic processes may act in concert to establish deterministic, precise, and reproducible territories of stochastic gene expression.

genomics↗

bioRxiv2023

Olfactory fear conditioning biases olfactory stem cell receptor fate

The main olfactory epithelium initiates the process of odor encoding. Recent studies have demonstrated intergenerationally inherited changes in the olfactory system in response to fear conditioning, resulting in increases in olfactory sensory neuron frequencies and altered responses to odors. We investigated changes in the cellular composition of the olfactory epithelium in response to an aversive stimulus. Here, we achieve volumetric cellular resolution to demonstrate that olfactory fear conditioning increases the number of odor-encoding neurons in mice that experience odor-shock conditioning (F0), as well as their unconditioned offspring (F1). We demonstrate that the increase in F0 is due, in part, to the biasing of the stem cell layer of the main olfactory epithelium. Detailed analysis of F1 behavior revealed subtle odor-specific differences between the offspring of unconditioned and conditioned parents, despite the absence of an active aversion to the conditioned odor. Thus, we reveal intergenerational regulation of olfactory epithelium composition in response to olfactory fear conditioning, providing insight into the heritability of acquired phenotypes. One-Sentence SummaryOlfactory fear conditioning induces heritable changes to the mouse olfactory system and biases neurogenesis and behavior in both parent and offspring.

neuroscience↗

bioRxiv2020

Racial and ethnic imbalance in neuroscience reference lists and intersections with gender

Discrimination against racial and ethnic minority groups exists in the academy, and the associated biases impact hiring and promotion, publication rates, grant funding, and awards. Precisely how racial and ethnic bias impacts the manner in which the scientific community engages with the ideas of academics in minority groups has yet to be fully elucidated. Citations are a marker of such community engagement, as well as a currency used to attain career milestones. Here we assess the extent and drivers of racial and ethnic imbalance in the reference lists of papers published in five top neuroscience journals over the last 25 years. We find that reference lists tend to include more papers with a White person as first and last author than would be expected if race and ethnicity were unrelated to referencing. We show that this imbalance is driven largely by the citation practices of White authors, and is increasing over time even as the field diversifies. To further explain our findings, we examine co-authorship networks and find that while the network has become markedly more integrated in general, the current degree of segregation by race/ethnicity is greater now than it has been in the past. Citing further from oneself on the network is associated with greater balance, but White authors preferential citation of White authors remains even at high levels of network exploration. We also quantify the effects of intersecting identities, determining the relative costs of gender and race/ethnicity, and their combination in women of color. Our findings represent a call to scientists and journal editors of all disciplines to consider the ethics of citation practices, and actions to be taken in support of an equitable future.

neuroscience↗