Biology subjects

Huang, G.

Publications and source records attributed to Huang, G..

At least 55 records · Page 3Linked to original sources

bioRxiv2024

Brain functional connectivity as a mediator between hematological metrics and cognitive decline in children with beta-thalassemia major

Children with beta-thalassemia major ({beta} -TM) are at risk of cognitive impairment, particularly in learning and memory. While cognitive deficits in the general population have been extensively studied, brain-based predictors for {beta}-TM children remain unexplored. This study used connectome-based predictive modeling (CPM) to examine whole-brain functional connectivity in 60 participants to predict cognitive performance. {beta}-TM children showed impaired cognitive abilities, as evidenced by lower Wechsler Intelligence Scale scores compared to controls. The identified brain regions, though not typically linked to cognitive performances, exhibited functional connectivity patterns associated with {beta}-TM, as confirmed by network-based statistics. Correlations between task performance, functional connectivity identified by the CPM, and hematological metrics were also examined. Significant correlations were found between the strength of functional network identified by CPM and hematological metrics, particularly hemoglobin levels and red blood cell distribution width. The study demonstrates that hematological factors influence cognitive performance indirectly through specific functional connectivity, providing new insights into the neural underpinnings of cognitive deficits in children with beta-thalassemia major.

neuroscience↗

bioRxiv2024

Organic opto-nanobiointerface enables multiscale biomodulation

Virtually all organic material on Earth has been produced converting solar energy through photosynthesis in chloroplasts, a sack-like, double membrane organelle in plants and algae, where transmembrane electron transfer occurs from lumen to stroma. Although animals hardly harness the power of photosynthesis, their bioelectrical signals extensively regulate complex electrophysiological behaviors, rendering it a superior target for biomedical innovation. Here, a crude structural mimicry of chloroplast has led us to discover that hollow sphere graphitic carbon nitride nanoparticles (hg-C3N4 NPs) endowed non-genetic, subcellular and intercellular photo-modulation of various excitable and non-excitable cells, accumulatively achieving modulation at tissue/organ function level. The homogeneous hg-C3N4 NPs showed responsiveness to light via both photoelectrochemical and photothermal mechanisms. The hg-C3N4 NPs can be spontaneously internalized with excellent cytocompatibility. Using a focusing laser, the hg-C3N4 NPs enable intracellular optical stimulation with subcellular resolution, inducing calcium transient release in multiple cells and propagation in primary cardiomyocytes and cardiac fibroblasts. At multicellular scale, optical pacing and synchronization of cardiomyocyte beating is readily achieved by LED. Further, we demonstrate that hg-C3N4 nanoparticles can be safely delivered into the mouse eye and elicit measurable cortical and behavioral light responses in a subset of animals in a model of advanced retinal degeneration. Finally, application of hg-C3N4 NPs to porcine retinal tissue ex vivo confirmed their modulation capability to directly activate RGCs activity under LED photostimulation. Taken together, these nanostructured biomimetic photocatalytic NPs offer high resolution, leadless optical probing, non-invasive delivery and great biocompatibility, serving as a versatile tool for addressing a range of complex biomedical challenges through subcellular, intercellular and tissue-level photo-modulation across a broad spectrum of scales.

bioengineering↗

bioRxiv2024

A Newborn F-box Gene Blocks Gene Flow by Selectively Degrading Phosphoglucomutase in Species Hybrids

The establishment of reproductive barriers such as postzygotic hybrid incompatibility (HI) remains the key to speciation. Gene duplication followed by differential functionalization has long been proposed as a major model underlying HI, but few supporting evidence exists. Here, we demonstrate that a new-born F-box gene, Cni-neib-1, of the nematode Caenorhabditis nigoni specifically inactivates an essential phosphoglucomutase encoded by Cbr-shls-1 in its sister species C. briggsae and their hybrids. Zygotic expression of Cni-neib-1 specifically depletes Cbr-SHLS-1, but not Cni-SHLS-1, in approximately 40 minutes starting from gastrulation, causing embryonic death. Cni-neib-1 is one of thirty-three paralogues emerging from a recent surge in F-box gene duplication events within C. nigoni, all of which are evolving under positive selection. Cni-neib-1 undergoes turnover even among C. nigoni populations. Differential expansion of F-box genes between the two species could reflect their distinctive innate immune responses. Collectively, we demonstrate how recent duplication of genes involved in protein degradation can cause unintended destruction of targets in hybrids that leads to HI, providing an invaluable insight into mechanisms of speciation. Significance statementUnderstanding how reproductive isolation forms and triggers speciation remains a central topic in evolutionary biology. In this study, the authors reveal a novel molecular mechanism that obstructs gene flow between the nematodes Caenorhabditis briggsae and C. nigoni. A recently evolved, species-specific F-box gene in C. nigoni selectively depletes an essential phosphoglucomutase enzyme in C. briggsae, leading to embryonic lethality in hybrids. This mechanism effectively prevents gene flow from C. nigoni to C. briggsae. This discovery underscores how a newborn gene, arising from recent gene duplication, can contribute to reproductive isolation by inadvertently disrupting a functionally important protein in hybrid offspring.

evolutionary biology↗

bioRxiv2024

Genomic and transcriptomic profiles influence on brain morphology and their interactions with pain sensitivity

Pain sensitivity varies widely among individuals and is influenced by a complex interplay of multi-omics factors, including genetic variations, gene expression, and brain morphology. While previous studies have identified associations between pain sensitivity and brain morphology, the exact mechanisms by which genetic profiles interact with brain structure to influence individual pain sensitivity remain unclear. In this study, we used aggregated datasets, including magnetic resonance imaging (MRI) and single nucleotide polymorphism (SNP) genotypes from 432 healthy participants, along with gene expression data from the Allen Human Brain Atlas (AHBA), to explore this multi-omics interplay. We first measured individual pain thresholds using laser stimuli and discovered structural brain differences between high and low pain sensitivity groups. We then identified two key gene sets with polarized expression patterns linked to brain morphology variations, enriched in functions related to ion channels and transmembrane transporter activities. Further statistical and mediation analyses revealed specific SNPs from ECM1, SLC24A2, and SCN9A genes that influence pain sensitivity, mediated through brain morphological changes in multiple basal ganglia regions. Our findings suggested that these SNPs not only affect brain structure but also modulate how individuals pain perception. Finally, we proposed an interpretation model integrating genomic, transcriptomic, and neuroimaging data, providing a detailed framework that illustrates the multi-omics contributions to individual difference in pain sensitivity. This study advances our understanding of how genetic and brain structural factors combine to shape pain perception, offering potential targets for personalized pain management strategies.

bioinformatics↗

bioRxiv2024

Polyelectrolyte mannan from diatoms reshapes sunlit ocean microbiome

Diatoms are a keystone phylum in Earths ecosystems, specializing in oxygen production and carbohydrate fixation that fuels global food webs. Diatoms host a microbiome, but how they preferentially collect bacteria with complementary traits remains unknown. Here we show that diatoms exude a C6-sulfated -1,3-mannan that serves as a selective carbon source for adapted bacteria. Its structure was resolved by NMR spectroscopy, chromatography, chemical synthesis, and enzymatic dissection. Biochemical, physiological, and structural analyses revealed that specialized Bacteroidota employ a four-enzyme pathway to metabolize this mannan. Metagenomic and transcriptomic data indicate that the mannan globally selects for bacteria carrying these enzymes and associated traits. Because the mannan provides only carbon, oxygen, sulfur, and hydrogen, bacteria must obtain other essential elements from alternative sources, reinforcing metabolic interdependence. We propose that diatoms use sulfated mannans to attract beneficial partners and exclude competitors, thereby engineering a microbiome that enhances their productivity and underpins carbon cycling. Significance statementEukaryotes host microbial partners that shape their health, yet how they selectively assemble beneficial microbes remains unclear. Using diatom microalgae as a model, we show they exude a sulfated mannan that nourishes highly adapted bacteria tracking them across the global ocean. Our findings suggest that single-celled eukaryotes can "domesticate" prokaryotes--analogous to how humans have domesticated animals--albeit on a microscopic scale. Dominating much of Earths aquatic surface, diatoms drive [~]20% of global photosynthesis. We propose that sulfated mannan contributes to this success by helping diatoms shape microbial partnerships that underpin planetary energy balance and atmospheric chemistry.

ecology↗

bioRxiv2024

Defect-Engineered Metal-Organic Frameworks as Nanocarriers for Pharmacotherapy: Insights into Intracellular Dynamics at The Single Particle Level

NanoMOFs are widely implemented in a host of assays involving drug delivery, biosensing catalysis, and bioimaging. Despite their wide use, the cell entry pathways and cell fate remain poorly understood. Here we have synthesized a new fluorescent nanoMOF integrating ATTO 655 into surface defects of colloidal nano UiO-66 that allowed us to track the spatiotemporal localization of Single nanoMOF in live cells. Density Functional Theory(DFT) reveals the stronger binding of ATTO 655 to the uncoordinated saturated Zr6 cluster nodes compared with phosphate and Alendronate Sodium (AL). Parallelized tracking of the spatiotemporal localization of tens of thousands of nanoMOFs and analysis using machine learning platforms revealed whether nanoMOFs remain outside as well as their cellular internalization pathways. To quantitatively assess their colocalization with endo/lysosomal compartments, we developed a colocalization proxy approach relying on the nanoMOF detection of particles in one channel to the signal in the corresponding endo/lysosomal compartments channel, considering signal vs local background intensity ratio (S/B) and signal-to-noise ratio (SNR). This strategy effectively mitigates the potential inflation of colocalization values arising from the heightened expression of signals originating from endo/lysosomal compartments, it also overcomes limitations of low SNRs in the endo/lysosomal compartments marker channel, which incapacitates any trajectory-trajectory colocalization assessment. The results accurately measure the amount of nanoMOFs colocalization in real-time from early (EE) to late endosomes(LE) and lysosomes(LY) and emphasize the importance of understanding their intracellular dynamics based on single-particle tracking (SPT) for optimal and safe drug delivery.

biophysics↗

bioRxiv2024

APOE regulates the transport of GM1

Apolipoprotein E (APOE) is responsible for lipid transport, including cholesterol transport and clearance. While the {varepsilon}4 allele of APOE (APOE4) is associated with a significant genetic risk factor for late-onset Alzheimers disease (AD), no mechanistic understanding of its contribution to AD etiology has been established yet. In addition to cholesterol, monosialotetrahexosylganglioside (GM1) is a crucial lipid component in cell membranes and has been implicated in promoting the aggregation of amyloid beta protein (A{beta}), a key protein associated with AD. Here, we ask whether there are direct interactions between APOE and GM1 that further impact AD pathology. We find that both APOE3 and APOE4 exhibit superior binding affinity to GM1 compared to cholesterol and have an enhanced cellular uptake to GM1 lipid structures than cholesterol lipid structures. APOE regulates the transport process of GM1 depending on the cell type, which is influenced by the expression of APOE receptors in different cell lines and alters GM1 contents in cell membranes. We also find that the presence of GM1 alters the secondary structure of APOE3 and APOE4 and enhances the binding affinity between APOE and its receptor low-density lipoprotein receptor (LDLR), consequently promoting the cellular uptake of lipid structures in the presence of APOE. To understand the enhanced cellular uptake observed in lipid structures containing 20% GM1, we determined the distribution of GM1 on the membrane and found that GM1 clustering in lipid rafts, thereby supporting the physiological interaction between APOE and GM1. Overall, we find that APOE plays a regulatory role in GM1 transport, and the presence of GM1 on the lipid structures influences this transport process. Our studies introduce a plausible direct link between APOE and AD etiology, wherein APOE regulates GM1, which, in turn, promotes A{beta} oligomerization and aggregation.

neuroscience↗

bioRxiv2024

Deep learning based genomic breeding of pest-resistant grapevine

Crop pests have profoundly deleterious effects on crop yield and food security. However, conventional pest control depends heavily on the utilization of insecticides, which develops strong pesticide resistance and concerns of food safety. Crop and their wild relatives display diverse levels of pest resistance, indicating the feasibility for breeding of pest-resistant crop varieties. In this study, we integrate deep learning (DL)/machine learning (ML) algorithms, plant phenomics and whole genome sequencing (WGS) data to conduct genomic selection (GS) of pest-resistance in grapevine. We employ deep convolutional neural networks (DCNN) to accurately calculate the severity of damage by pests on grape leaves, which achieves a classification accuracy of 95.3% (Visual Geometry Group 16, VGG16, for binary trait) and a correlation coefficient of 0.94 in regression analysis (DCNN with Pest Damage Score, DCNN-PDS, for continuous trait). We apply DL models to predict and integrate phenotype (both binary and continuous) along with WGS data from 231 grape accessions, conducting Genome-Wide Association Studies (GWAS). This analysis detects a total of 69 QTLs, encompassing 139 candidate genes involved in pathways associated with pest resistance, including jasmonic acid (JA), salicylic acid (SA), ethylene, and other related pathways. Furthermore, through the combination with transcriptome data, we identify specific pest-resistant genes, such as ACA12 and CRK3, which play distinct roles in resisting herbivore attacks. Machine learning-based GS demonstrates a high accuracy (95.7%) and a strong correlation (0.90) in predicting the leaf area damaged by pests as binary and continuous traits in grapevine, respectively. In general, our study highlights the power of DL/ML in plant phenomics and GS, facilitating genomic breeding of pest-resistant grapevine.

plant biology↗

bioRxiv2024

MarmoPose: A Deep Learning-Based System for Real-time Multi-Marmoset 3D Pose Trackingp

The ability to track positions and poses (body parts) of multiple monkeys in a 3D space in real time is highly desired by non-human primate (NHP) researchers in behavioral and systems neuroscience because it allows both analyzing social behaviors among multiple NHPs and performing close-loop experiments (e.g., delivering sensory or optogenetics stimulation during a particular behavior). While a number of animal pose tracking systems have been reported, nearly all published work lacks the real-time analysis capacity. Existing methods for tracking freely moving animals have been developed primarily for rodents which typically move on a 2D space. In contrast, NHPs roam in a 3D space and move at a much faster speed than rodents. We have designed a real-time 3D pose tracking system (MarmoPose) based on deep learning to capture and quantify social behaviors in natural environment of a highly social NHP species, the common marmosets (Callithrix jacchus) which has risen to be an important NHP model in neuroscience research in recent years. This system has minimum hardware requirement and can accurately track the 3D poses (16 body locations) of multiple marmosets freely roaming in their homecage. It employs a marmoset skeleton model to optimize the 3D poses and estimate invisible body locations. Furthermore, it achieves high inference speed and provides an online processing module for real-time closed-loop experimental control based on the 3D poses of marmosets. While this system is optimized for marmosets, it can also be adapted for other large animal species in a typical housing environment with minimal modifications.

animal behavior and cognition↗

bioRxiv2024

STING Licensing of Type I Dendritic Cells Potentiates Antitumor Immunity

Stimulator of interferon genes (STING) is an immune adaptor protein that senses cyclic GMP-AMP (cGAMP) in response to self or microbial cytosolic DNA as a danger signal. STING is ubiquitously expressed in diverse cell populations including cancer cells with distinct cellular functions such as activation of type I interferons, autophagy induction, or triggering apoptosis. It is not well understood whether and which subsets of immune cells, stromal cells, or cancer cells are particularly important for STING-mediated antitumor immunity. Here using a polymeric STING-activating nanoparticle (PolySTING) with a "shock-and-lock" dual activation mechanism, we show type 1 conventional dendritic cell (cDC1) is essential for STING-mediated rejection of multiple established and metastatic murine tumors. STING status in the host but not in the cancer cells (Tmem173-/-) is important for antitumor efficacy. Specific depletion of cDC1 (Batf3-/-) or STING deficiency in cDC1 (XCR1creSTINGfl/fl) abolished PolySTING efficacy, whereas depletion of other myeloid cells had little effect. Adoptive transfer of wildtype cDC1 in Batf3-/- mice restored antitumor efficacy while transfer of cDC1 with STING or IRF3 deficiency failed to rescue. PolySTING induced a specific chemokine signature in wildtype but not Batf3-/- mice. Multiplexed immunohistochemistry analysis of STING-activating cDC1s in resected tumors correlates with patient survival while also showing increased expressions after neoadjuvant pembrolizumab therapy in non-small cell lung cancer patients. Therefore, we have defined that a subset of myeloid cells is essential for STING-mediated antitumor immunity with associated biomarkers for prognosis. One Sentence SummaryA "shock-and-lock" nanoparticle agonist induces direct STING signaling in type 1 conventional dendritic cells to drive antitumor immunity with defined biomarkers

immunology↗

bioRxiv2023

Auditory High Entropy Response (A-HER): A Novel Paradigm for Studying Brain Processing of Uncertain Information

This paper introduces a novel experimental paradigm - Auditory High Entropy Response (A-HER), which maximizes the information entropy of auditory stimulus sequences. This allows us to study how the brain processes complex information, rather than isolated individual events. Our analysis of the frequency response of the frontal theta rhythm induced by A-HER indicated a significant increase in signal-to-noise ratio and repeatability compared to zero-entropy Auditory Steady-State Response (A-SSR) and low-entropy mismatch negativity (MMN). We further investigated whether the A-HER response was induced by stimulus sequence differences or uncertainty, and studied its propagation rules. Different principles between evoked and entrained were found in A-HER and A-SSR. In conclusion, the A-HER paradigm, by maximizing stimulus sequence uncertainty, offers a new approach to analyzing how the brain processes uncertain information. It has potential for diagnosing and researching neurological and mental diseases, and for brain-computer interfaces, thus potentially impacting neuroscience, cognitive science, and psychology.

bioengineering↗

bioRxiv2023

Quantitative dynamics of intracellular NMN by genetically encoded biosensor

Nicotinamide mononucleotide (NMN) is a major precursor for NAD+ metabolism with promising effects in treating NAD+- and aging-related pathologies. However, measuring live cell NMN dynamics was not possible, leaving key questions in intracellular NMN uptake and regulation unanswered. Here we developed a genetically encoded bioluminescent sensor to quantify subcellular NMN in live cells by fusing engineered NMN-responsive binding domain to bioluminescent and fluorescent proteins from BRET pairs. The sensor dissected the multimechanistic uptake of extracellular NMN and precursors in live cells. We then captured the notably low mitochondrial NMN content and the thereafter vulnerable NMN/NAD+ ratio and SARM1 activation in mitochondria, establishing NMN/NAD+ ratio as an important parameter in evaluating NAD+ boosting strategies. Moreover, we characterized the signature of major NAD+ regulating enzymes on NMN and NMN/NAD+ ratios, in which Slc25a45 was identified to be a potential mitochondrial NMN transporter for its unique fingerprint on mitochondrial NMN/NAD+ ratio.

cell biology↗

bioRxiv2023

Cell autonomous role of leucine-rich repeat kinase in protection of dopaminergic neuron survival

Mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common genetic cause of Parkinsons disease (PD), which is the leading neurodegenerative movement disorder characterized by the progressive loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc). However, whether LRRK2 mutations cause PD and degeneration of DA neurons via a toxic gain-of-function or a loss-of-function mechanism is unresolved and has pivotal implications for LRRK2-based PD therapies. In this study, we investigate whether LRRK2 and its functional homologue LRRK1 play an essential, intrinsic role in DA neuron survival through the development of DA neuron-specific LRRK conditional double knockout (cDKO) mice. We first generated and characterized floxed LRRK1 and LRRK2 mice and then confirmed that germline deletions of the floxed LRRK1 and LRRK2 alleles result in null mutations, as evidenced by the absence of LRRK1 and LRRK2 mRNA and protein in the respective homozygous deleted mutant mice. We further examined the specificity of Cre-mediated recombination driven by the dopamine transporter-Cre (DAT-Cre) knockin (KI) allele using a GFP reporter line and confirmed that DAT-Cre-mediated recombination is restricted to DA neurons in the SNpc. Crossing these validated floxed LRRK1 and LRRK2 mice with DAT-Cre KI mice, we then generated DA neuron-restricted LRRK cDKO mice and further showed that levels of LRRK1 and LRRK2 are reduced in dissected ventral midbrains of LRRK cDKO mice. While DA neuron-restricted LRRK cDKO mice of both sexes exhibit normal mortality and body weight, they develop age-dependent loss of DA neurons in the SNpc, as demonstrated by the progressive reduction of DA neurons in the SNpc of LRRK cDKO mice at the ages of 20 and 24 months but the unaffected number of DA neurons at the age of 15 months. Moreover, DA neurodegeneration is accompanied with increases of apoptosis and elevated microgliosis in the SNpc as well as decreases of DA terminals in the striatum, and is preceded by impaired motor coordination. Taken together, these findings provide the unequivocal evidence for the importance of LRRK in DA neurons and raise the possibility that LRRK2 mutations may impair its protection of DA neurons, leading to DA neurodegeneration in PD.

neuroscience↗

bioRxiv2023

Microglia Regulate Sleep via Calcium-Dependent Modulation of Norepinephrine Transmission

Sleep interacts reciprocally with immune system activity, but its specific relationship with microglia - the resident immune cells in the brain - remains poorly understood. Here we show that microglia can regulate sleep through a mechanism involving Gi-coupled GPCRs, intracellular Ca2+ signaling, and suppression of norepinephrine transmission. Chemogenetic activation of microglia Gi signaling strongly promoted sleep, whereas pharmacological blockade of Gi-coupled P2Y12 receptors decreased sleep. Two-photon imaging showed that P2Y12/Gi activation elevated microglia intracellular Ca2+, and blockade of this Ca2+ elevation largely abolished the Gi-induced sleep increase. Microglia Ca2+ level also increased at natural wake-to-sleep transitions, caused partly by reduced norepinephrine. Furthermore, imaging of norepinephrine activity with its biosensor showed that microglia P2Y12/Gi activation significantly reduced norepinephrine, partly by increasing the adenosine concentration. Thus, microglia can regulate sleep through reciprocal interactions with norepinephrine transmission.

neuroscience↗

bioRxiv2023

A Highly Efficient Aorta-Gonad-Mesonephros-Like Definitive Hemogenic Endothelium From Human Pluripotent Stem Cells

Summary/AbstractHuman pluripotent stem cells are a tremendous tool to model early human development and disease including their use in the in vitro generation of blood cell fates. Hematopoietic progenitors and stem cells are the primary source of blood and the immune system from early development to adulthood and arise through successive waves of hemogenic mesoderm either in the yolk sac or embryo proper. Researchers have long sought a tractable human model for observing and distinguishing these waves of hematopoiesis in the dish for human developmental and disease modeling. Here we report a high-efficiency method for differentiating human pluripotent stem cells into an aorta-gonad-mesonephros-like definitive hemogenic mesoderm capable of giving rise to definitive hematopoietic progenitor and stem cells. The hematopoietic progenitor and stem cells exhibit robust multilineage in vitro colony forming potential. Gene expression analysis and single cell sequencing strongly support the developmental timing and notion that the pluripotent stem cell derived hematopoietic stem and progenitors are strikingly like bone fide hematopoietic stem cells. The hematopoietic progenitors can be subsequently differentiated into polarized macrophage and T-cells in vitro. Minimal silencing was observed upon differentiation of the pluripotent stem cells to hematopoietic lineages when conducting gene editing. Finally, upon engraftment into immunodeficient animals the hematopoietic progenitors and stem cells differentiate into multiple lineages including B-cells, T-cells, NK-cells, and monocytes.

developmental biology↗

bioRxiv2023

WBSCR16 Determines Metabolic Flexibility Via Regulating Mitochondrial 16S rRNA Maturation

Mitochondria play significant roles in energy homeostasis by dissipating excess calories. However, the key proteins in mitochondrial govern metabolically flexibility remain poorly understand. Herein, we generated adipose specific Wbscr16-/-mice and cells, both of which exhibited a preference for fat utilization and displayed dramatic mitochondrial changes. We demonstrated that WBSCR16 is essential for the specific cleavage of 16S rRNA-tRNALeu, leading to the production of maturated 16S rRNA, which in turn controls mitochondrial large ribosomal assembly. Importantly, WBSCR16 was identified as a 16S rRNA-binding protein that directly interacts with RNase P subunit MRPP3. Furthermore, evidence showed that WBSCR16 ablation promotes energy wasting via lipid cycling in BAT, leading to excess energy expenditure and resistance to obesity. Conversely, cells and mice with WBSCR16 overexpression preferred to glucose utilization. These findings suggest that WBSCR16 is the key mitochondrial switch protein between glucose and lipid metabolism, making it a promising target for the development of fat busting drug.

cell biology↗

bioRxiv2023

Decoded EEG Neurofeedback-Guided Cognitive Reappraisal Training for Emotion Regulation

Neurofeedback is an innovative self-training that adjusts and enhances brain function. One of the more studied application scenarios with neurofeedback training is emotion regulation. Compared with regional brain activity-informed neurofeedback techniques, neurofeedback protocols using the decoded brain states as feedback signals could make the setting of regulation targets more specific and objective. In the present study, we constructed an EEG neurofeedback-guided cognitive reappraisal training protocol for emotion regulation. Forty-two healthy participants (20 females; 22.4{+/-}2.2 years old) were recruited and were randomly assigned to either the neurofeedback group or the control group. During the training process, we calculate the real-time self-regulation performance on the evoked emotion based on the decoded emotional states and fed it back to the subjects as the feedback signal. According to our results, real-time feedback of the regulation effect helps subjects improve emotion regulation performance for emotional stimuli with low positive valence. Further analysis of selected EEG features for emotion classification revealed the neural correlates with neurofeedback training. This newly proposed neurofeedback training protocol is a promising treatment for emotion-related mental disorders, with the potential to be a low-cost and high-portability brain-based, non-invasive, neural modulation technique.

neuroscience↗

bioRxiv2023

Reciprocal polarization imaging of complex media.

The vectorial evolution of polarized light interaction with a medium can reveal its microstructure and anisotropy beyond what can be obtained from scalar light interaction. Anisotropic properties (diattenuation, retardance, and depolarization) of a complex medium can be quantified by polarization imaging by measuring the Mueller matrix. However, polarization imaging in the reflection geometry, ubiquitous and often preferred in diverse applications, has suffered a poor recovery of the mediums anisotropic properties due to the lack of suitable decomposition of the Mueller matrices measured inside a backward geometry. Here, we present reciprocal polarization imaging of complex media after introducing reciprocal polar decomposition for backscattering Mueller matrices. Based on the reciprocity of the optical wave in its forward and backward scattering paths, the anisotropic diattenuation, retardance, and depolarization of a complex medium are determined by measuring the backscattering Mueller matrix. We demonstrate reciprocal polarization imaging in various applications for quantifying complex non-chiral and chiral media, uncovering their anisotropic microstructures with remarkable clarity and accuracy. Reciprocal polarization imaging will be instrumental in imaging complex media from remote sensing to biomedicine and will open up new applications of polarization optics in reflection geometry.

biophysics↗