Biology subjects

Chang, C.

Publications and source records attributed to Chang, C..

At least 37 records · Page 2Linked to original sources

bioRxiv2025

Polyamine homeostasis in vivo relies primarily on transport

Polyamines are essential metabolites present in all cells, but their regulation in vivo remains poorly understood. Little is known about whether tissues maintain distinct polyamine setpoints, how these setpoints are established, or whether such differences underlie selective vulnerability in disease. Here, we applied single-cell polyamine measurements in living Caenorhabditis elegans to map tissue polyamine levels and their regulatory dependencies. Three principles emerge: (i) Across differentiated tissues, steady-state polyamine pools are maintained primarily by transporter-mediated import rather than de novo synthesis. (ii) The intestine functions as a systemic regulator: perturbing intestinal polyamines affects organism-wide levels, and intestine-specific rescue restores systemic balance. (iii) Neurons maintain markedly low polyamine pools and undergo subtype-specific developmental reprogramming, switching polyamine acquisition strategies as they mature. These findings define core principles of tissue-specific polyamine regulation in vivo and provide a framework for developing therapeutic strategies to restore polyamine balance.

cell biology↗

bioRxiv2025

TREM2 macrophages are associated with enhanced response to PD-1 blockade in human hepatocellular carcinoma

Macrophages are known to dampen tumor immunity. However, identifying druggable targets that modulate these cells to improve existing immunotherapies has been limited by a dearth of studies identifying macrophages that associate with pathological response to immune checkpoint blockade. To fulfill this unmet clinical need, we leveraged transcriptional and spatial profiling of specimens collected from a Phase II clinical trial studying neoadjuvant PD-1 blockade in patients with hepatocellular carcinoma (HCC). We determined that the intratumoral abundance of TREM2-expressing macrophages and serological levels of soluble TREM2 are elevated in patients who responded to PD-1 blockade, compared to non-responders. We validated these findings in a second HCC cohort and in the IMbrave150 trial. These highlight the robust potential for TREM2 macrophages to predict therapeutic responses of HCC to immunotherapy. Therefore, our study provides a novel basis for the use of TREM2 macrophages to strategize treatment for patients with HCC to maximize therapeutic benefit.

immunology↗

bioRxiv2025

Walking Selectively Modulates Behaviorally Relevant Auditory Responses According to Stride Cycle Phase

Perception in natural environments unfolds while the body is in motion, yet how locomotion shapes cortical computations for fine-grained and dynamic scene analysis remains unclear. Here, we combined over-ground walking with mobile EEG and a transitional click-train paradigm to test how natural locomotion influences auditory processing in humans. Participants listened to two-segment click trains in which a subtle inter-click-interval (ICI) change signaled a pitch shift and performed a task-engaged change-detection task while either sitting or walking; an independent cohort also completed a passive-listening version. Walking elevated behavioral detection thresholds and slowed responses, indicating reduced sensitivity to fine temporal changes. Neurally, locomotion produced a response-component-specific attenuation: activity time-locked to the ICI transition--the change response previously linked to temporally integrative updating of an ongoing auditory object--was strongly reduced, whereas the offset response was largely preserved and onset responses were only modestly affected. Critically, this modulation persisted during passive listening and was selectively amplified near the perceptual threshold during task-engaged detection, revealing an interaction between motor state and cognitive demand. Thus, natural locomotion does not uniformly degrade hearing; instead, it preferentially down-weights a behaviorally critical, temporally demanding stage of auditory processing, offering a framework for understanding how motor-cognitive state shapes auditory scene analysis in the moving brain.

neuroscience↗

bioRxiv2025

A novel, high-density CRISPR activation platform for mapping cancer dependencies and resistance pathways ex vivo and in vivo

CRISPR activation (CRISPRa) enables precise, locus-specific upregulation of gene expression, offering potential for both ex vivo and in vivo applications. However, the lack of scalable, high-coverage tools has limited its use in comprehensive genetic screens, particularly in murine models. Here, we introduce Partita, a next-generation, whole-genome CRISPRa sgRNA platform designed for unparalleled efficiency and depth in gene activation studies. Partita employs a high-density targeting strategy, deploying 10 sgRNAs per transcription start site, structured into five gene family-specific sub-libraries to maximize transcriptional induction. To demonstrate its capabilities, we performed a series of large-scale screens: an in vitro enrichment/depletion screen in iBMDMs, whole-genome CRISPRa screens in a double-hit lymphoma model to uncover genes driving resistance to pro-apoptotic drugs (venetoclax, nutlin-3a, etoposide), and an in vivo whole-genome screen identifying accelerators of Myc-driven lymphomagenesis. Each experiment revealed both expected and novel regulators of cellular phenotypes, with a high validation rate in secondary assays. By enabling robust, high-throughput gain-of-function screening, Partita unlocks new avenues for functional genomics and expands the toolkit for discovering key drivers of biological processes across diverse research fields.

cancer biology↗

bioRxiv2025

Psoriasin inhibits microbial growth in food by metal sequestering

Food spoilage is a significant economic and environmental concern, and it is estimated that [~]30% of fresh food is destroyed due to food spoilage between harvest to consumer. Current food preservatives are chemicals that are associated with various health risks and often have limited effectiveness under certain conditions like pH and temperature. Consequently, theres a growing need to develop effective, natural, and economical food preservatives. Herein, we studied the natural protein psoriasin as a potential food preservative. Psoriasin is naturally secreted in the oral cavity and has an effective and validated antimicrobial activity which makes it a potentially effective and safe protein-based food preservative. Indeed, our preliminary results show promising antimicrobial activity of the recombinant protein against food-related microbial organisms in vitro and in various food types. In addition, it is recombinantly expressed at high levels, which could set a cost-effective manufacturing process. These results set psoriasin as a safe and effective natural food preservative, addressing consumer demand for healthier food options and reducing food waste.

biochemistry↗

bioRxiv2025

Heart spheroids from primary cells for studying cardiac development

Organoids can be broadly classified based on their source: either from primary cells or from in vitro stem cell differentiation. Organoids derived from primary cells have been developed for various organs such as the liver, intestine, and colon, demonstrating significant value in disease modeling and drug screening. However, primary cell-derived heart organoids have not yet been reported. In this study, we developed heart organoid-like spheroids using murine atrial and ventricular cells. We demonstrated that these spheroids largely preserved the cell lineages present in vivo. We further evaluated their responses to treatment with growth factors. Subsequently, we fused atrial and ventricular spheroids to observe the migration patterns of different cell types. Then, we generated mixed spheroids composed of cells from different heart regions or organs and found that region- or organ-specific cells tended to cluster together. Notably, liver- and intestine-derived cells promoted cardiomyocyte maturation within these mixed organoids. Finally, we performed a fibroblast ablation assay in heart spheroids derived from transgenic mice and observed the effects on other cell lineages. Overall, we successfully generated heart spheroids from murine primary cells and demonstrated their in vivo-like characteristics. Compared to stem cell-derived organoid systems, this primary cell-derived approach holds great promise for translational research due to its potential to better preserve native cellular features.

developmental biology↗

bioRxiv2025

Functional MRI Signatures of Autonomic Physiology in Aging

While traditionally regarded as "noise", blood-oxygenation-level-dependent (BOLD) fMRI fluctuations coupled to systemic physiology--such as heart rate and respiratory changes--also hold valuable information about brain vascular properties and autonomic function. In this study, we leverage these physiological BOLD signals to characterize age-related changes in brain physiology. Using a large dataset from the Lifespan Human Connectome Project Aging study, we investigated how the spatiotemporal BOLD-fMRI signatures of autonomic physiology, specifically heart rate and respiratory variation, change with advancing age. Our findings reveal that aging is associated with globally slower respiratory fMRI responses, alongside faster cardiac fMRI responses and enhanced brain-cardiac signal coupling. Moreover, we show that the impact of age on physiological fMRI signals exhibits a notable turning point after age 60, suggesting a critical role of declining vascular health and autonomic function in aging. The potential impact of age-related changes in brain structure, tissue perfusion, and in-scan arousal states on the identified physiological fMRI patterns is also tested and discussed. Altogether, our results underscore significant age effects in the fMRI signatures of systemic physiology, emphasizing the pivotal role of altered vascular properties and autonomic function in aging. Methodologically, this study also demonstrates the utility of resting-state fMRI for extracting multi-parametric information about brain physiology, offering new biomarker opportunities that complement established functional connectivity metrics.

physiology↗

bioRxiv2025

The Physiological Component of the BOLD Signal: Impact of Age and Heart Rate Variability Biofeedback Training

Aging is associated with declines in autonomic nervous system (ANS) function, including reduced heart rate variability (HRV), impaired neurovascular coupling, and diminished cerebrovascular responsiveness--factors that may contribute to cognitive decline and neurodegenerative diseases. Understanding how aging alters physiological signal integration in the brain is crucial for identifying potential interventions to promote brain health. This study examines age-related differences in how cardiac and respiratory fluctuations influence the blood oxygenation level-dependent (BOLD) signal, using two independent resting-state fMRI datasets with concurrent physiological recordings from younger and older adults. Our findings reveal significant age-related reductions in the percent variance of the BOLD signal explained by heart rate (HR), respiratory variation (RV), and end-tidal CO2, particularly in regions involved in autonomic regulation, including the orbitofrontal cortex, anterior cingulate cortex, insula, basal ganglia, and white matter. Cross-correlation analysis also revealed that younger adults exhibited stronger HR-BOLD coupling in white matter, as well as a more rapid BOLD response to RV and CO2 in gray matter. Additionally, we investigated the effects of heart rate variability biofeedback (HRV-BF) training, a non-invasive intervention designed to modulate heart rate oscillations. The intervention altered physiological-BOLD coupling in an age- and training-dependent manner: older adults who underwent HRV-BF to enhance HR oscillations exhibited a shift toward younger-like HR-BOLD coupling patterns, while younger adults who trained to suppress HR oscillations showed increased CO2-BOLD coupling. These findings suggest that HRV-BF may help mitigate age-related declines in autonomic or cerebrovascular function. Overall, this study underscores the role of physiological dynamics in brain aging and highlights the importance of considering autonomic function when interpreting BOLD signals. By demonstrating that HRV-BF can modulate physiological-BOLD interactions, our findings suggest a potential pathway for enhancing cerebrovascular function and preserving brain health across the lifespan.

neuroscience↗

bioRxiv2025

Inactivation of the Fusobacterium nucleatum Rnf complex reduces FadA-mediated amyloid formation and tumor development

The Gram-negative anaerobe Fusobacterium nucleatum is an oral oncobacterium that promotes colorectal cancer (CRC) development with the amyloid-forming cell surface adhesin FadA integral to CRC tumorigenesis. We describe here molecular genetic studies uncovering a novel mode of metabolic regulation of FadA-mediated tumor formation by a highly conserved respiratory enzyme known as the Rnf complex. First, we show that genetic disruption of Rnf, via rnfC deletion, significantly reduces the level of fadA transcript, accompanied by a near-complete abolishment of the precursor form of FadA (pFadA), reduced assembly of FadA at the mature cell pole, and severe defects in the osmotic stress-induced formation of FadA amyloids. We show further that the Rnf complex regulates three response regulators (CarR, ArlR, and S1), which modulate the expression of pFadA, without affecting fadA transcript. Consistent with our hypothesis that these response regulators control factors that process FadA, deletion of rnfC, carR, arlR, or s1 each impairs expression of the signal peptidase gene lepB, and FadA production is nearly abolished by CRISPR-induced depletion of lepB. Importantly, while rnfC deletion does not affect the ability of the mutant cells to adhere to CRC cells, rnfC deficiency significantly diminishes the fusobacterial invasion of CRC cells and formation of spheroid tumors in vitro. Evidently, the Rnf complex modulates the expression of the FadA adhesin and tumorigenesis through a gene regulatory network consisting of multiple response regulators, each controlling a signal peptidase that is critical for the post-translational processing of FadA and surface assembly of FadA amyloids. IMPORTANCEThe Rhodobacter nitrogen-fixation (Rnf) complex of Fusobacterium nucleatum plays an important role in the pathophysiology of this oral pathobiont, since genetic disruption of this conserved respiratory enzyme negatively impacts a wide range of metabolic pathways, as well as bacterial virulence in mice. Nonetheless, how Rnf deficiency weakens the virulence potential of F. nucleatum is not well understood. Here, we show that genetic disruption of the Rnf complex reduces surface assembly of adhesin FadA and FadA-mediated amyloid formation, via regulation of signal peptidase LepB by multiple response regulators. As FadA is critical in the carcinogenesis of colorectal cancer (CRC), the ability to invade CRC cells and promote spheroid tumor growth is strongly diminished in an Rnf-deficient mutant. Thus, this work uncovers a molecular linkage between the Rnf complex and LepB-regulated processing of FadA - likely via metabolic signaling - that maintains the virulence potential of this oncobacterium in various cellular niches.

microbiology↗

bioRxiv2025

The relationship of white matter tract orientation to vascular geometry in the human brain

The white matter of the human brain exhibits highly ordered anisotropic structures of both axonal nerve fibers and cerebral vasculature. Separately, the anisotropic nature of white matter axons and white matter vasculature have been shown to cause an orientation dependence on various MRI contrasts used to study the structure and function of the brain; however, little is known of the relationship between axonal and vascular orientations. Thus, the aim of this study is to compare the orientation between nerve fibers and vasculature within the white matter. To do this, we use diffusion MRI and susceptibility weighted imaging acquired in the same healthy young adult volunteers and analyze the alignment between white matter fibers and blood vessels in different brain regions, and along different pathways, to determine the degree of alignment between these structures. We first describe vascular orientation throughout the brain and note several regions with consistent orientations across individuals. Next, we find that vasculature does not necessarily align with the dominant direction of white matter in many regions, but, due to the presence of crossing fiber populations, does align with at least some white matter within each MRI voxel. Even though the spatial patterns of blood vessels run in parallel to several white matter tracts, they do not do so along the entire pathway, nor for all pathways, suggesting that vasculature does not supply/drain blood in a tract-specific manner. Overall, these findings suggest that the vascular architecture within the white matter is closely related to, but not the same as, the organization of neural pathways. This study contributes to a better understanding of the microstructural arrangement of the brain and may have implications for interpreting neuroimaging data in health and disease.

neuroscience↗

bioRxiv2025

Sex specific disruptions in Protein Kinase Cγ signaling in a mouse model of Spinocerebellar Ataxia Type 14

Spinocerebellar Ataxia Type 14 (SCA14) is an autosomal dominant neurodegenerative disease caused by mutations in the gene encoding protein kinase C gamma (PKC{gamma}), a Ca2+/diacylglycerol (DG)-dependent serine/threonine kinase dominantly expressed in cerebellar Purkinje cells. These mutations impair autoinhibitory constraints to increase the basal activity of the kinase, resulting in deficits in the cerebellum that are not observed upon simple deletion of the gene, and severe ataxia. To better understand the phenotypic impact of aberrant PKC{gamma} signaling in disease pathology, we developed a knock-in murine model of the SCA14 mutation {Delta}F48 in PKC{gamma}. This fully penetrant mutation is severe in humans and is mechanistically informative as it has high basal activity but is unresponsive to agonist stimulation. Genetic, behavioral, and molecular testing revealed that {Delta}F48 PKC{gamma} SCA14 mice have ataxia related phenotypes and an altered cerebellar phosphoproteome, effects that are more severe in male mice. Analysis of existing human data reveal that SCA14 has a significantly earlier age of onset for males compared with females. Our data from this clinically relevant mutation suggest that enhanced basal activity of PKC{gamma} is necessary and sufficient to cause ataxia and that treatment strategies to modulate aberrant PKC{gamma} may be particularly beneficial in males. SummaryNew mouse model of Spinocerebellar Ataxia Type 14 containing a clinically relevant mutation in PKC{gamma} identified underlying drivers of the disease and neuroprotection in females.

neuroscience↗

bioRxiv2025

Developmental Variations in Recurrent Spatiotemporal Brain Propagations from Childhood to Adulthood

The brain undergoes profound structural and functional transformations from childhood to adolescence. Convergent evidence suggests that neurodevelopment proceeds in a hierarchical manner, characterized by heterogeneous maturation patterns across brain regions and networks. However, the maturation of the intrinsic spatiotemporal propagations of brain activity remains largely unexplored. This study aims to bridge this gap by delineating spatiotemporal propagations from childhood to early adulthood. By leveraging a recently developed approach that captures time-lag dynamic propagations, we characterized intrinsic dynamic propagations along three axes: sensory-association (S-A), task-positive to default networks (TP-D), and somatomotor-visual (SM-V) networks, which progress towards adult-like brain dynamics from childhood to early adulthood. Importantly, we demonstrated that as participants mature, there is a prolonged occurrence of the S-A and TP-D propagation states, indicating that they spend more time in these states. Conversely, the prevalence of SM-V propagation states declines during development. Notably, top-down propagations along the S-A axis exhibited an age-dependent increase in occurrence, serving as a superior predictor of cognitive scores compared to bottom-up S-A propagation. These findings were replicated across two independent cohorts (N = 677 in total), emphasizing the robustness and generalizability of these findings. Our results provide new insights into the emergence of adult-like functional dynamics during youth and their role in supporting cognition.

neuroscience↗

bioRxiv2025

Survival Reinforced Transfer Learning for Multicentric Proteomic Subtyping and Biomarker Discovery

Omics-based molecular subtyping in large-scale and multicentric cohort studies is a prerequisite for proteomics-driven precision medicine (PDPM). However, keeping the subtypes with robust molecular features and significant associations with prognosis among different cohorts is challenging due to the biological heterogeneity and technical inconsistency. Herein, we propose a subtyping algorithm, named Survival Reinforced Patient Stratification (SRPS), to adapt the known subtypes from the discovery cohort to another by simultaneously preserving the distinct prognosis and molecular characteristics of each subtype. SRPS has been benchmarked on simulated and real-world datasets, where it shows a 12% increase in classification accuracy and possesses the best prognostic discriminations. Moreover, based on the calculated subtype significance score, an unpopular protein, Peptidylprolyl Isomerase C (PPIC), was identified as the top-1 remarkable protein for subtyping the hepatocellular carcinoma (HCC) patients with the worst prognosis. Eventually, PPIC was experimentally proved to be a pro-cancer protein in HCC, confirming our work as a practice of interpretable machine learning guided biological discovery in PDPM research.

bioinformatics↗

bioRxiv2025

Unravel the start element and promoter architecture across the domain Bacteria

Core promoters comprise multiple elements whose interaction with RNA polymerase initiates transcription. Despite decades of research, substantial sequence and length variation of promoter elements has hindered efforts to elucidate their function and the evolutionary diversity of transcriptional regulation. Combining massively parallel assays, biophysical modeling, and functional validation, we systematically dissected the promoter architecture upstream of experimentally determined transcription start sites in 49 phylogenetically diverse bacterial genomes (GC content: 27.8-72.1%). We identified a conserved 3-bp promoter element, termed start, that dictates transcription start site selection and enhances transcription. We uncovered a four-region organization within the variable spacer element, whose sequence composition modulates transcription by up to 600-fold. We showed that the discriminator element is conserved in Terrabacteria but diverse in Gracilicutes, the two major bacterial clades. High discriminator sequence diversity in Gracilicutes likely reflects diversifying evolution, enabling promoter-encoded regulation to orchestrate global gene expression in response to growth rate changes. Together, our findings reveal broad conservation of bacterial promoter organization while highlighting regulatory divergence of promoter elements and RNA polymerase between Terrabacteria and Gracilicutes. Sequence and functional similarities between bacterial promoter elements and their archaeal and eukaryotic counterparts further suggest a shared evolutionary origin of promoter architecture.

microbiology↗

bioRxiv2025

Simultaneous EEG-PET-MRI identifies temporally coupled, spatially structured hemodynamic and metabolic dynamics across wakefulness and NREM sleep

Sleep entails significant changes in cerebral hemodynamics and metabolism. Yet, the way these processes evolve throughout wakefulness and sleep and their spatiotemporal dependence remain largely unknown. Here, by integrating a novel functional PET technique with simultaneous EEG-fMRI, we reveal a tightly coupled temporal progression of global hemodynamics and metabolism during the descent into NREM sleep, with large hemodynamic fluctuations emerging as global glucose metabolism declines, both of which track EEG arousal dynamics. Furthermore, we identify two distinct network patterns that emerge during NREM sleep: an oscillating, high-metabolism sensorimotor network remains active and dynamic, whereas hemodynamic and metabolic activity in the default-mode network is suppressed. These results elucidate how sleep diminishes awareness while preserving sensory responses, and uncover a complex, alternating balance of neuronal, hemodynamic, and metabolic dynamics in the sleeping brain. This work also demonstrates the potential of EEG-PET-MRI to explore neuro-hemo-metabolic dynamics underlying cognition and arousal in humans.

neuroscience↗

bioRxiv2025

Integrated Techniques for Extracellular Particle Separation and Single-Particle Multiparametric Characterization to Track Cancer Biomarkers from Tissue to Biofluids

Gastric cancer (GC) remains a formidable global health challenge, with late-stage diagnosis and high recurrence rates resulting in poor patient outcomes. This study explores the potential of advanced technologies, namely Bessel Beam Excitation Separation Technology (BEST) and multiparametric biochip assay (MBA), to track single extracellular vesicle and particle (EVP) cargo from organs of pathology into biofluids such as plasma and saliva. Using GC as a study model, we conducted high throughput, multiparametric analyses of EVPs derived from plasma, saliva, and tissue samples. Our findings demonstrate the feasibility of these techniques in isolating and characterizing EVPs, revealing consistent EVP morphology and size across biofluids. Furthermore, differential expression patterns of the developed and validated salivary GC biomarkers, miR-140-5p and miR-301a-3p, were observed in GC patient biofluids, supporting the diagnostic relevance of EVP cargo. Notably, saliva emerged as the most promising biofluid for GC diagnosis, achieving superior Receiver Operating Characteristic (ROC) curve values compared to plasma and tissue. This study highlights the role of BEST and MBA in advancing single-EVP analysis and elucidating EVP trafficking, paving the way for future diagnostic applications of EVP cargo.

cancer biology↗

bioRxiv2024

Quantitative mapping of cerebrovascular reactivity amplitude and delay with breath-hold BOLD fMRI when end-tidal CO2 quality is low

Cerebrovascular reactivity (CVR), the ability of cerebral blood vessels to dilate or constrict in response to a vasoactive stimulus, is a clinically useful measure of cerebrovascular health. CVR is often measured using a breath-hold task to modulate blood CO2 levels during an fMRI scan. Measuring end-tidal CO2 (PETCO2) with a nasal cannula during the task allows CVR amplitude to be calculated in standard units (vascular response per unit change in CO2, or %BOLD/mmHg) and CVR delay to be calculated in seconds. The use of standard units allows for normative CVR ranges to be established and for CVR comparisons to be made across subjects and scan sessions. Although breath holding can be successfully performed by diverse patient populations, obtaining accurate PETCO2 measurements requires additional task compliance; specifically, participants must breathe exclusively through their nose and exhale immediately before and after each breath hold. Meeting these requirements is challenging, even in healthy participants, and this has limited the translational potential of breath-hold fMRI for CVR mapping. Previous work has focused on using alternative regressors such as respiration volume per time (RVT), derived from respiration-belt measurements, to map CVR. Because measuring RVT does not require additional task compliance from participants, it is a more feasible measure than PETCO2. However, using RVT does not produce CVR amplitude in standard units. In this work, we explored how to achieve CVR amplitude maps, in standard units, and CVR delay maps, when breath-hold task PETCO2 data quality is low. First, we evaluated whether RVT could be scaled to units of mmHg using a subset of PETCO2 data of sufficiently high quality. Second, we explored whether a PETCO2 timeseries predicted from RVT using deep learning allows for more accurate CVR measurements. Using a dense-mapping breath-hold fMRI dataset, we showed that both rescaled RVT and rescaled, predicted PETCO2 can be used to produce maps of CVR amplitude in standard units and CVR delay with strong absolute agreement to ground-truth maps. The rescaled, predicted PETCO2 regressor resulted in superior accuracy for both CVR amplitude and delay. In an individual with regions of increased CVR delay due to Moyamoya disease, the predicted PETCO2 regressor also provided greater sensitivity to pathology than RVT. Ultimately, this work will increase the clinical applicability of CVR in populations exhibiting decreased task compliance.

neuroscience↗

bioRxiv2024

Multimodal state-dependent connectivity analysis of arousal and autonomic centers in the brainstem and basal forebrain

Vigilance is a continuously altering state of cortical activation that influences cognition and behavior and is disrupted in multiple brain pathologies. Neuromodulatory nuclei in the brainstem and basal forebrain are implicated in arousal regulation and are key drivers of widespread neuronal activity and communication. However, it is unclear how their large-scale brain network architecture changes across dynamic variations in vigilance state (i.e., alertness and drowsiness). In this study, we leverage simultaneous EEG and 3T multi-echo functional magnetic resonance imaging (fMRI) to elucidate the vigilance-dependent connectivity of arousal regulation centers in the brainstem and basal forebrain. During states of low vigilance, most of the neuromodulatory nuclei investigated here exhibit a stronger global correlation pattern and greater connectivity to the thalamus, precuneus, and sensory and motor cortices. In a more alert state, the nuclei exhibit the strongest connectivity to the salience, default mode, and auditory networks. These vigilance-dependent correlation patterns persist even after applying multiple preprocessing strategies to reduce systemic vascular effects. To validate our findings, we analyze two large 3T and 7T fMRI datasets from the Human Connectome Project and demonstrate that the static and vigilance-dependent connectivity profiles of the arousal nuclei are reproducible across 3T multi-echo, 3T single-echo, and 7T single-echo fMRI modalities. Overall, this work provides novel insights into the role of neuromodulatory systems in vigilance-related brain activity.

neuroscience↗