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The neural mechanisms setting the lower limit of conscious visual perception in humans is not fully understood. Here the authors show by correlating human vision experiments and non-human primate retina recordings that primates rely on the retinal ON pathway in perception of the dimmest light increments, and that nonlinear thresholding in this pathway eliminates single photons and neural noise thereby allowing perception of minute differences in light intensity.

This study introduces a novel recording technique for simultaneously measuring excitatory and inhibitory conductances of retinal ganglion cells to show that excitatory and inhibitory inputs are strongly correlated, thereby cancelling each other. Furthermore, dynamic clamp is used to introduce these conductance changes into the cell with or without correlations, and it is found that, as predicted by theoretical work, correlations significantly increase reliability of the spiking response.

The 4D Nucleome Project demonstrates the use of genomic assays and computational methods to measure genome folding and then predict genomic structure from DNA sequence, facilitating the discovery of potential effects of genetic variants, including variants associated with disease, on genome structure and function.

Neural adaptation, crucial for sensory processing, is absent in conventional machine learning models of the visual system. Here the authors show that adding photoreceptor adaptation in these models better predicts retina responses under natural vision.

Humans can see in conditions from darkened cinemas to bright sun because cone photoreceptors adapt their mean output to the current light conditions; here, a second site of adaptation is identified, in the retina between the cone bipolar cells and ganglion cells. The two adaptation mechanisms are complementary with cone adaptation occurring at higher light levels and together they extend the operating range of human vision.

Analysis of cell types and circuit design of the primary rod pathway in zebrafish suggests that this specialized downstream circuit for rod signalling has been established before the divergence of teleost fish and mammals.

Ribbon synapses in our sensory nervous system are central to hearing and sight, yet little is known about how these synapses are assembled and maintained during development. In this study, authors use live imaging techniques to monitor ribbon appearance, loss and maintenance in a retinal circuit during development to show that nascent synapses comprising of both ribbons and PSD95 are more stable over time compared to contacts without ribbons.

Nearby retinal ganglion cells show correlated activity in the absence of visual stimuli and these correlations are propagated across the population. A combination of recordings and computational modeling suggest that shared synaptic input is the origin of this synchrony.

Recording from primate retinal ganglion cells, the authors find that cone noise, traversing the retina through diverse pathways, accounts for most of the noise and correlations in the retinal output. This constrains how higher centers exploit signals carried by parallel visual pathways.

The origin and functional importance of noise in mammalian cones is poorly understood. Here, the authors find that channel noise and fluctuations in cGMP dominate cone noise, that adaptation in cones affects signal and noise differently, and that cones generate less noise than previously thought. These results help reconcile cone noise and behavioral sensitivity.

Immune cells mostly enter lymph nodes (LN) from blood circulation, but whether afferent lymphatics contributes to LN entry is unclear. Here, the authors show, using a photo-convertible reporter, that T cells in afferent lymphatics frequently enter LN and become arrested in the subcapsular sinus, with chemokines and integrins further guiding their migration in the LN.

The authors utilize information theory to show that four of the output pathways in the primate retina encode predictive information about visual motion. They further show the nonlinear circuit mechanisms that contribute to this computation.

Fine-scale synchrony of neural activity determines the nature of neural coding, but its underlying mechanisms are unclear. Here the authors find that coincident electrical and chemical synaptic inputs are nonlinearly integrated in overlapping retinal ganglion cell dendrites to produce synchronous spiking.

The authors attempt to improve existing retinal models by incorporating measurements of the physiological properties and connectivity of only the primary excitatory circuitry of the retina. The resulting model predicts ganglion cell responses to a variety of spatial patterns and provides a direct correspondence between circuit connectivity and retinal output.

A satisfactory understanding of how natural stimuli are encoded by neural circuits has remained elusive. Advances in machine learning provide new approaches to this problem by merging constraints imposed by stimulus statistics and behavioral goals.

Inhibition of histone deacetylation allows the transcription factor Ascl1 to bind to key gene loci in Müller glia and drive the functional generation of retinal neurons in adult mice.

As guidelines, therapies and literature on cancer variants expand, the lack of consensus variant interpretations impedes clinical applications. CIViC is a public-domain, crowd-sourced and adaptable knowledgebase of evidence for the clinical interpretation of variants in cancer, designed to reduce barriers to knowledge sharing and alleviate the variant-interpretation bottleneck.

The kinetochore is a large protein complex that assembles on centromeric DNA and captures microtubules to mediate chromosome separation. These authors report the first purification of functional kinetochores. They also show that kinetochore particles maintain load-bearing associations with assembling and disassembling ends of single microtubules and that tension increases the lifetimes of the attachments directly. These results provide evidence that tension selectively stabilises kinetochore–microtubule interactions.