bioRxiv Science⌕ Search

Biology subjects

Taylor, L.

Publications and source records attributed to Taylor, L..

At least 19 recordsLinked to original sources

Enhancing cortical electrophysiological signatures of sleep overrides ER stress responses in sleep-deprived mice

Sleep deprivation (SD) triggers characteristic changes in the cortical electroencephalogram (EEG) during waking and sleep, as well as upregulating molecular signatures of neuronal activity, synaptic plasticity, and endoplasmic reticulum (ER) stress. This includes the induction of the unfolded protein response (UPR), the primary marker and adaptive mechanism of ER stress. Yet how cortical neuronal activity during SD contributes to the induction of these molecular signatures remains unknown. Here we investigate whether manipulating cortical activity during SD with a physiological stimulation paradigm (flickering light stimulation, FLS) affects the induction of the UPR. As expected, SD alone upregulated activity-dependent and UPR-related genes in cortex and led to increased EEG slow-wave activity (SWA) during subsequent NREM sleep, an electrophysiological signature of sleep need. Delivering FLS during SD, however, prevented the upregulation of activity- and UPR-related genes while inducing an additional increase in SWA during subsequent sleep. Further analysis of neuronal firing revealed that FLS induced brief neuronal silent (OFF) periods in awake animals during stimulation, thereby shifting cortical activity towards a brain state resembling sleep. These findings suggest that physiological manipulation of cortical activity during waking is sufficient to dissociate molecular signatures of ER stress from electrophysiological markers of sleep pressure. We propose that global sleep wake history and cortical network dynamics differentially regulate activity-dependent transcription and the accumulation of sleep pressure.

neuroscience↗

Allergic airway inflammation protects against SARS-CoV-2 and MERS-CoV disease but promotes fatal SARS-CoV-1 immunopathology

Epidemiological, clinical, and experimental data suggest that allergic asthma may have protective effects against severe Coronavirus Disease 2019 (COVID-19) but are often conflicting between different models of infection and epidemiological analyses. Allergic asthma is characterized by type 2 (T2) inflammation, mucus hypersecretion, and airway remodeling. We used a house dust mite (HDM) respiratory exposure model to determine how preexisting allergic inflammation alters the pathogenesis of three highly pathogenic coronaviruses, SARS-CoV-1, SARS-CoV-2, and MERS-CoV. HDM treatment induced canonical features of allergic asthma, including goblet cell hyperplasia, mucin hypersecretion, eosinophil recruitment, M2 macrophage polarization, and induction of IL-13. Across multiple SARS-CoV-2 variants, HDM treated mice exhibited reduced viral titers, less weight loss, diminished lung immunopathology, and improved survival rates. Similar protection was observed in a mouse model of MERS-CoV, with reduced lethality, lower viral burden, and blunted cytokine storm signatures in HDM treated mice. In contrast, allergic airway inflammation exacerbated SARS-CoV-1 pathogenesis, as HDM-treated mice developed fulminant alveolar inflammation, severe weight loss, elevated pro-inflammatory cytokines and chemokines, and increased mortality despite having reduced virus titer. Thus, in mice, allergic airway inflammation exerts opposing virus specific effects on coronavirus pathogenesis. These results reconcile conflicting epidemiological and mechanistic studies across coronavirus epidemics and highlight the need to consider host allergic status as a key variable influencing disease outcome from emerging coronaviruses.

microbiology↗

Lactate-fueled hydride transfer metabolon drives breast cancer metastasis

Metabolic plasticity of cancer cells plays a major role in metastasis. Use of alternative carbon fuels (e.g., lactate) boosts metabolic plasticity, but the underlying mechanisms remain obscure. We show that lactate dehydrogenase B (LDHB) cooperates with the hydride ion transfer complex (HTC) comprised of pyruvate carboxylase (PC), malic enzyme (ME1) and malate dehydrogenase (MDH1) to form a metabolon that confers metabolic flexibility through lactate assimilation under physiological conditions. HTC/LDHB metabolon assembles in the aggressive breast cancer subtypes and reprograms nicotinamide adenine dinucleotide (NAD) metabolism to promote migration, invasion and escape from anoikis - thereby driving metastasis. Altogether, this work identifies a lactate-fueled metabolon that propels metastatic dissemination of breast cancer.

Cancer Biology↗

Computationally hybridized pathogenic mammarenavirus receptor binding domains reveal cryptic variants that elicit cross-neutralizing immune responses

The pathogenic mammarenaviruses, Machupo (MACV) and Junin (JUNV), are under evolutionary pressure to leverage human transferrin receptor 1 (hTfR1) for cellular entry while evading host immune responses during zoonosis. We now structurally and functionally investigate cryptic, computationally hybridized JUNV-MACV GP1 sequence variants. We then evaluate the ability of those variants to facilitate internalization of pseudotyped virus-like particles (PVs) into human cells and their recognition by neutralizing antibodies, including plasma from JUNV convalescent patients. We further compare the cryoEM structures of hTfR1-bound MACV GP1 to those of two functional hTfR1-bound MACV-JUNV hybrid GP1 variants that enable robust PV internalization and are also recognized by cross-neutralizing antibodies. Immunization with these variants demonstrates they and other hybrid GP1 sequences can elicit cross-reactive, neutralizing antibodies, supporting a model in which sequence adaptation within GP1 balances receptor recognition with immune evasion. This may inform the rational design of broadly neutralizing GP1-targeted antiviral therapies.

biophysics↗

A phage display library to dissect antibody responses to human coronavirus spike proteins

Coronaviruses are widespread human pathogens with demonstrated pandemic potential. We developed a phage immunoprecipitation sequencing (PhIP-Seq) library, C-Spike, enabling the profiling of serum antibody responses to coronavirus spike proteins. The C-Spike library includes peptides from 49 Alpha- and Betacoronavirus spike proteins, including pandemic coronaviruses (SARS-CoV-1, SARS-CoV-2, MERS-CoV), seasonal coronaviruses (HKU1, OC43, 229E, NL63), and selected animal coronaviruses of spillover interest. The library includes a series of 46 amino acid-long peptides covering each spike, with adjacent tiles overlapping by 23 amino acids. Additionally, the library contains alanine-scanned versions of each peptide, tiling three alanine residues at every position across the peptide length, allowing for precise identification of motifs important for antibody binding. We validate C-Spike and its associated bioinformatic analysis pipeline using control antibodies and sera with known reactivity. C-Spike complements existing approaches like neutralization assays to enable deep characterization of antibody responses to coronavirus spike proteins, enabling precise determination of sites important for antibody binding.

immunology↗

Sex- and ketogenesis-dependent effects of intermittent fasting against diet-induced obesity and fatty liver disease

ABSTRACTSIntermittent fasting (IF) improves metabolic health, yet the requirement for hepatic ketogenesis in mediating these benefits remains unclear. Here, we investigated how hepatic ketogenesis contributes to the metabolic and hepatic effects of IF in male and female mice. In the human liver, ketogenesis-associated genes showed sex-dependent correlations with inflammatory and fibrotic pathways. In mice, fasting increased circulating ketone bodies, with females exhibiting a greater rise, indicating intrinsic sex differences in ketone metabolism. IF reduced body weight and adiposity in both sexes, and these systemic benefits persisted despite antisense oligonucleotide (ASO)-mediated knockdown of hepatic Hmgcs2. In contrast, hepatic benefits were sex- and ketogenesis-dependent. IF markedly reduced steatosis and fibrosis in male mice, but these improvements were attenuated or abolished when hepatic ketogenesis was disrupted. Female mice showed minimal hepatic benefit from IF and displayed heightened susceptibility to steatosis, fibrosis, and inflammatory activation under ketogenic insufficiency. Single-cell transcriptomic analyses identified neutrophils and myofibroblasts as key responders to hepatocyte-derived ketone bodies, and IF suppressed neutrophil-driven inflammatory signaling in a ketogenesis-dependent manner in males but not females. Together, these findings demonstrate that while systemic metabolic improvements from IF are largely ketogenesis-independent, the hepatic anti-steatotic and anti-fibrotic effects of IF are sexually dimorphic and require intact hepatic ketogenesis.

physiology↗

FuChi: A cell cycle biosensor for investigating cell-cycle kinetics during avian development.

The ability to monitor the proliferative status of live cells both in vitro and in vivo over time has revolutionised our understanding of development, growth and disease. This was first made possible by fluorescent ubiquitination-based cell cycle indicator (Fucci) technology, which distinguishes specific cell cycle phases through the reciprocal degradation of fluorescently tagged, truncated forms of human CDT1 and GMNN proteins. Fucci genetic systems have been successfully implemented in transgenic mice, zebrafish, and axolotls. To date, no viable, stably expressing Fucci line has been developed in an avian species. Although a range of continuously improving Fucci constructs have been developed in recent years, existing in vivo Fucci models remain limited because they rely on older reporter technology that fails to distinguish cells in S, G2, and M phases or to label cells in early G1. As a result, these models can be challenging to interpret and their utility for continuous cell tracking and precise analysis of cell-cycle dynamics is limited. Here, we introduce FuChi, a multicistronic Fucci-expressing chicken line incorporating a newly optimised reporter construct composed of an mCerulean-tagged Histone H1.0 linker protein fused via a self-cleaving 2A peptide to the tandem Fucci(CA) cell cycle biosensor, with additional epitope tags included for detection in fixed tissues. We show that this system accurately discriminates and permits tracking of cells in G1, S, G2, and M phases both in vitro and in vivo, enabling faithful visualisation of cell cycle status in intact tissues and organs. Using FuChi embryos, we mapped proliferation dynamics across developing tissues, analysed cell cycle states of migrating cells, and performed live imaging of early embryos. These latter experiments revealed that transition from S phase may be a key morphogenetic event during gastrulation as mesendoderm cells egress from the primitive streak to form embryonic structures including the prechordal plate. Pairing this advanced reporter with the intrinsic experimental advantages of the chicken embryo positions FuChi as a premier in vivo system for studying cell-cycle kinetics in development, delivering clear technological improvements over current Fucci models. FuChi chickens provide a powerful new resource for studying embryonic development, organ growth, tissue homeostasis, disease processes, and infection responses.

developmental biology↗

Interleukin 10 controls the balance between tolerance, pathogen elimination and immunopathology in birds.

Effective mucosal immunity in the intestine involves a fine balance between tolerance of the microbiome, recognition and elimination of pathogens, and inflammatory tissue injury. The anti-inflammatory cytokine IL10 regulates these processes in the intestines of mice and humans; the anti-inflammatory activity of IL10 is also conserved in birds. To determine the function of IL10 in avian mucosal immunity, we generated germ line modifications of the chicken IL10 locus to abolish or reduce IL10 expression. In vitro analysis of macrophage response to lipopolysaccharide confirmed the loss of IL10 protein expression, the lack of dosage compensation in heterozygotes, and prevention of autocrine inhibition of nitric oxide production in homozygous IL10 knockout macrophages. IL10-deficiency significantly altered the composition of the caecal microbiome, but unlike IL10-deficient mice and humans, IL10-deficient chickens did not exhibit spontaneous colitis. Following experimental challenge with Salmonella enterica serovar Typhimurium or Campylobacter jejuni in IL10-deficient chickens, enhanced clearance of the pathogens was associated with elevated transcription of pro-inflammatory genes and increased infiltration of inflammatory cells into gut mucosa. In IL10-deficient chickens challenged with the parasite Eimeria tenella, pathogen clearance was accelerated but caecal lesions were more severe and weight gain was compromised. Neither the heterozygous IL10 knockout nor a homozygous IL10 enhancer mutation had a major effect on pathogen clearance or inflammation in any of the challenge models. Our findings highlight the intrinsic compromise in mucosal immune response and have important implications for the development of strategies to combat avian and zoonotic pathogens in poultry.

immunology↗

The mammalian SKI complex is a broad-spectrum antiviral drug target that upregulates cellular cholesterol to inhibit viral replication

There is a need for the development of broad-spectrum antiviral compounds that can act as first line therapeutic countermeasures to emerging viral infections. Host-directed approaches present a promising avenue of development and carry the benefit of mitigating risks of viral escape mutants. We have previously found the SKI (super killer) complex to be a broad-spectrum, host-target with our lead compound ("UMB18") showing activity against influenza A virus, coronaviruses, and filoviruses. The SKI complex is a cytosolic RNA helicase and we previously found that UMB18 inhibited viral RNA production but did not further define the mechanism. Here, we demonstrate that UMB18 directly binds to SKIC8 of the SKI complex and through transcriptomic analysis of UMB18 treated A549 cells revealed an upregulation of genes in the mevalonate pathway which drives cholesterol synthesis. Further investigation validated the genetic upregulation and confirmed an increase in total cellular cholesterol. This upregulation was dependent on the sterol regulatory element binding proteins (SREBPs) and their regulator SCAP, the major regulators for cholesterol and fatty acid synthesis. Depletion of the SREBPs or SCAP with siRNA, or extraction of cholesterol with methyl {beta}-cyclodextrin attenuated UMB18 antiviral activity, emphasizing the role of increased cholesterol synthesis in this mechanism of action. Our findings further define the antiviral mechanism of a developmental host-directed therapeutic approach with broad applicability against emerging viral pathogens. Author SummaryThe COVID-19 pandemic has underscored the urgent need for effective countermeasures to novel and emerging viral pathogens. Our research presented here builds upon our previously published data on an experimental novel antiviral compound termed UMB18. We have found this compound capable of inhibiting replication of influenza A virus, coronaviruses and the filoviruses Marburg and Ebola virus, but did not fully define a mechanism of action. In this work, we demonstrate that UMB18 exerts antiviral activity by modulating cellular cholesterol levels. By targeting the SKI complex, UMB18 triggers an increase in endogenous cellular cholesterol which disrupts the fine balance viruses rely on for efficient infection. We demonstrate that this mechanism inhibits replication of SARS-CoV-2, revealing a previously undescribed host-directed strategy for antiviral intervention. These findings highlight UMB18s potential as a broad-spectrum antiviral agent and pave the way for further research into its mechanism and therapeutic applications, offering a promising avenue for development of antiviral countermeasures to current, novel and emerging pathogens.

microbiology↗

Parallel neuroinflammatory pathways to cerebrovascular injury and amyloid-beta in Alzheimer's disease

ImportanceWhile the hallmark pathologies of amyloid-beta (A{beta}) and tau in Alzheimers disease (AD) are well documented and even part of the definition, upstream neuroinflammation is thought to play an important role but remains poorly understood. ObjectivesWe tested whether two distinct neuroinflammatory markers are associated with cerebrovascular injury and A{beta}, and whether these markers are associated with plasma phosphorylated tau (pTau) concentration, medial temporal lobe (MTL) cortical and hippocampal atrophy, and memory deficits. We examined neuroinflammatory markers plasma YKL-40 and GFAP, due to previous conflicting evidence relating YKL-40 and GFAP to AD pathogenic markers. DesignCross-sectional data from a community observational study (Biomarker Exploration in Aging, Cognition, and Neurodegeneration - BEACoN) were included. SettingAll participants were enrolled in a single site, at University of California, Irvine. Participants126 participants were included if they had at least one of the following measures available: neuropsychological data, MRI, A{beta}-PET, or plasma. ExposuresPlasma YKL-40 and plasma glial fibrillary acidic protein (GFAP) levels. Main outcomes and measuresWhite matter hyperintensity (WMH) volume, 18F-florbetapir (FBP) PET mean SUVR, plasma phosphorylated tau (pTau-217) concentration, MTL cortical thickness, hippocampal volume, and memory function assessed by Rey Auditory Verbal Learning Test. Using path analysis, we tested whether higher plasma YKL-40 and GFAP are associated with WMH and A{beta}, and whether these converge to downstream markers of tauopathy, MTL neurodegeneration, and memory deficits. ResultsIn older adults without dementia (N=126, age=70.60+6.29, 62% women), we found that higher plasma YKL-40 concentration was associated with greater WMH volume, while higher plasma GFAP concentration was related to increased FBP SUVR. Further, higher plasma GFAP, WMH and FBP SUVR were independently associated with increased pTau-217. In turn, plasma pTau-217 was associated with reduced MTL cortical thickness and hippocampal volume. Subsequently, only reduced hippocampal volume was related to lower memory function. Conclusions and RelevanceNeuroinflammatory markers contribute to parallel pathways of cerebrovascular injury and A{beta}, which converge to tau-associated neurodegeneration and memory deficits in older adults. These observations underscore the need for a more comprehensive approach to developing an AD framework and treatment strategies. KEY POINTSO_ST_ABSQuestionC_ST_ABSHow does neuroinflammation impact downstream features of cerebrovascular injury and amyloid-beta (A{beta}) in Alzheimers disease? FindingsIn this study of 126 older adults without dementia, we found evidence for two distinct neuroinflammatory pathways that lead to neurodegeneration and memory deficits. One path involves plasma YKL-40 and its impact on cerebrovascular injury, as measured by white matter hyperintensities (WMH) on MRI scans. The other involves plasma glial fibrillary acidic protein (GFAP) and its impact on A{beta} deposition measured via 18F-florbetapir (FBP) PET. Both pathways converged on tauopathy, measured by plasma pTau-217, which was associated with lower medial temporal lobe (MTL) cortical thickness and hippocampal volume, and consequently, memory deficits. MeaningInflammation acts on Alzheimers disease mechanisms via multiple distinct and parallel pathways which converge downstream onto neurodegeneration. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC="FIGDIR/small/616579v1_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@2d3c39org.highwire.dtl.DTLVardef@1ccc453org.highwire.dtl.DTLVardef@6d40bdorg.highwire.dtl.DTLVardef@b543cb_HPS_FORMAT_FIGEXP M_FIG C_FIG Credit: BioRender was used to help create this graphical abstract.

neuroscience↗

Achieving Single Cell Acoustic Localisation with Deactivation Super Resolution

Super-resolution optical microscopy enables optical imaging of cells, molecules and other biological structures beyond the diffraction limit. However, no similar method exists to super-resolve specific cells with ultrasound. Here we introduce Deactivation Super Resolution (DSR), an ultrasound imaging method that uses the acoustic deactivation of genetically encodable contrast agents to super-resolve individual cells with ultrasound as they navigate through structures that cannot be resolved by conventional imaging methods. DSR takes advantage of gas vesicles, which are air-filled sub-micron protein particles that can be expressed in genetically engineered cells to produce ultrasound contrast. Our experimental results show that DSR can distinguish sub-wavelength microstructures that standard B-mode ultrasound images fail to resolve by super- localizing individual mammalian cells. This study provides a proof of concept for the potential of DSR to serve as a super- resolution ultrasound technique for individual cell localization, opening new horizons in the field.

bioengineering↗

Amyloid-β deposition in basal frontotemporal cortex is associated with selective disruption of temporal mnemonic discrimination

Cerebral amyloid-beta (A{beta}) accumulation, a hallmark pathology of Alzheimers disease (AD), precedes clinical impairment by two to three decades. However, it is unclear whether A{beta} contributes to subtle memory deficits observed during the preclinical stage. The heterogenous emergence of A{beta} deposition may selectively impact certain memory domains, which rely on distinct underlying neural circuits. In this context, we tested whether specific domains of mnemonic discrimination, a neural computation essential for episodic memory, exhibit specific deficits related to early A{beta} deposition. We tested 108 cognitively unimpaired human older adults (66% female) who underwent 18F-florbetapir positron emission tomography (A{beta}-PET), and a control group of 35 young adults, on a suite of mnemonic discrimination tasks taxing object, spatial, and temporal domains. We hypothesized that A{beta} pathology would be selectively associated with temporal discrimination performance due to A{beta}s propensity to accumulate in the basal frontotemporal cortex, which supports temporal processing. Consistent with this hypothesis, we found a dissociation in which generalized age-related deficits were found for object and spatial mnemonic discrimination, while A{beta}-PET levels were selectively associated with deficits in temporal mnemonic discrimination. Further, we found that higher A{beta}-PET levels in medial orbitofrontal and inferior temporal cortex, regions supporting temporal processing, were associated with greater temporal mnemonic discrimination deficits, pointing to the selective vulnerability of circuits related to temporal processing early in AD progression. These results suggest that A{beta} accumulation within basal frontotemporal regions may disrupt temporal mnemonic discrimination in preclinical AD, and may serve as a sensitive behavioral biomarker of emerging AD progression.

neuroscience↗

ADAM interact with large protein complexes to regulate Histone modification, gene expression and splicing.

Cranial neural crest (CNC) cells are key stem cells that contribute to most of the facial structures in vertebrates. ADAM (A Disintegrin And Metalloprotease) proteins are essential for the induction and migration of the CNC. We have shown that Adam13 associates with the transcription factor Arid3a to regulate gene expression. Here we show that Adam13 modulates Histone modifications in the CNC. We show that Arid3a binding to the tfap2 promoter depends on the presence of Adam13. This association promotes the expression of one tfap2 variant expressed in the CNC that uniquely activates the expression of gene critical for CNC migration. We show that both Adam13 and human ADAM9 associate with proteins involved in histone modification and RNA splicing, a function critically affected by the loss of Adam13. We propose that ADAMs may act as extracellular sensors to modulate chromatin availability, leading to changes in gene expression and splicing.

developmental biology↗

Spike-to-excite: photosensitive seizures in biologically-realistic spiking neural networks

Photosensitive Epilepsy (PE) is a neurological disorder characterized by seizures triggered by harmful visual stimuli, such as flashing lights and high-contrast patterns. The mechanisms underlying PE remain poorly understood, and to date, no computational model has captured the phenomena associated with this condition. Biologically detailed spiking networks trained for efficient prediction of natural scenes have been shown to capture V1-like characteristics. Here, we show that these models display seizure-like activity in response to harmful stimuli while retaining healthy responses to non-provocative stimuli when post-synaptic inhibitory connections are weakened. Notably, our adapted model resembles the motion tuning and contrast gain responses of excitatory V1 neurons in mice with optogenetically reduced inhibitory activity. We offer testable predictions underlying the pathophysiology of PE by exploring how reduced inhibition leads to seizure-like activity. Finally, we show that artificially injecting pulsating input current into the model units prevents seizure-like activity and restores baseline function. In summary, we present a model of PE that offers new insights to understand and treat this condition.

neuroscience↗

The microRNA156/SPL9 module mediates auxin response to facilitate apical hook maintenance in Arabidopsis

Auxin coordinates cell growth by promoting or inhibiting cell expansion during etiolated seedling development, but whether and how microRNA modules participate in this process remains unclear. Here, we show the miRNA156/SQUAMOSA PROMOTER-BINDING-PROTEIN-LIKE9 (miR156/SPL9) module is critical for skotomorphogenesis. Perturbation of the miR156/SPL9 module affected skotomorphogenesis, as the loss of miR156 function or SPL9 de-repression led to shorter hypocotyl, higher hook angle, and delayed hook opening. Opposing phenotypes were observed in dark-grown spl9 and miR156-overexpressing seedlings. Importantly, loss of miR156-dependent SPL9 regulation triggered apical hook formation even under reduced levels of endogenous auxin. miR156-targeted SPL9 arrested cell expansion by repressing small auxin-up RNA19 (SAUR19) gene in a FRUITFULL (FUL)-dependent and independent manner. The conserved miR156/SPL9/15 module also affects skotomorphogenesis in tomato, impacting its successful soil emergence. Our findings unravel how the miR156/SPL9 module plays a pivotal role in the auxin network coordinating apical hook development to enable appropriate seedling emergence.

plant biology↗

The dynamic gene regulatory landscape of the mouse brain in response to sleep deprivation

Sleep deprivation (SD) negatively impacts nearly all brain functions including cognition, memory consolidation and metabolism. However, the gene regulatory networks that underlie these biological effects are not well understood. In order to identify these networks, we conducted a multiomic analysis to analyse how gene expression, chromatin accessibility, enhancer activity and DNA methylation change with acute SD in mice. By studying three brain regions involved in different aspects of sleep - the cortex (CTX), dentate gyrus (DG), and suprachiasmatic nucleus (SCN) - we found that the effects of SD on the multiome varied widely, impacting physiological processes specific to each area, from spine formation in the dentate gyrus to neuropeptide release in the SCN. Our integrated analysis showed that distinct brain region-specific networks of regulatory factors dynamically alter the epigenomic landscape in response to SD to orchestrate transcriptional responses. These findings provide new understanding of the regulatory grammar encoded within the genome, which enables a general physiological signal like SD to produce unique effects in a tissue-specific context.

neuroscience↗

Temporal prediction captures key differences between spiking excitatory and inhibitory V1 neurons

Neurons in primary visual cortex (V1) respond to natural scenes with a sparse and irregular spike code that is carefully balanced by an interplay between excitatory and inhibitory neurons. These neuron classes differ in their spike statistics, tuning preferences, connectivity statistics and temporal dynamics. To date, no single computational principle has been able to account for these properties. We developed a recurrently connected spiking network of excitatory and inhibitory units trained for efficient temporal prediction of natural movie clips. We found that the model exhibited simple and complex cell-like tuning, V1-like spike statistics, and, notably, also captured key differences between excitatory and inhibitory V1 neurons. This suggests that these properties collectively serve to facilitate efficient prediction of the sensory future.

neuroscience↗

Temporal prediction captures retinal spiking responses across animal species

The retinas role in visual processing has been viewed as two extremes: an efficient compressor of incoming visual stimuli akin to a camera, or as a predictor of future stimuli. Addressing this dichotomy, we developed a biologically-detailed spiking retinal model trained on natural movies under metabolic-like constraints to either encode the present or to predict future scenes. Our findings reveal that when optimized for efficient prediction[~] 100 ms into the future, the model not only captures retina-like receptive fields and their mosaic-like organizations, but also exhibits complex retinal processes such as latency coding, motion anticipation, differential tuning, and stimulus-omission responses. Notably, the predictive model also more accurately predicts the way retinal ganglion cells respond across different animal species to natural images and movies. Our findings demonstrate that the retina is not merely a compressor of visual input, but rather is fundamentally organized to provide the brain with foresight into the visual world.

neuroscience↗