Visual system

  • Article
    | Open Access

    The signal-to-noise ratio is a key consideration when selecting a magnetic resonance imaging protocol. Thermal noise is major issue, especially in high resolution functional images. Here the authors introduce a method to suppress thermal noise in functional images without losses in spatial precision, increasing the signal-to-noise ratio.

    • Luca Vizioli
    • , Steen Moeller
    •  & Kamil Uğurbil
  • Article
    | Open Access

    The Drosophila visual system first computes motion in the dendrites of T4 and T5 neurons via a linear mechanism that uses ON and OFF information. Here, the authors show that the Tm9, Tm2, and CT1 neurons provide both ON and OFF information to direction-selective T5 cells in the OFF pathway.

    • Giordano Ramos-Traslosheros
    •  & Marion Silies
  • Article
    | Open Access

    In the cerebral cortex, information is processed by multiple hierarchically organized areas, reciprocally connected via feedforward and feedback circuits. Here the authors show that in primate visual cortex, feedforward projection neurons receive monosynaptic feedback contacts selectively from the area to which they project.

    • Caitlin Siu
    • , Justin Balsor
    •  & Alessandra Angelucci
  • Article
    | Open Access

    The relative roles of visual, parietal, and frontal cortex in working memory have been actively debated. Here, the authors show that distraction impacts visual working memory representations in primary visual areas, indicating that these regions play a key role in the maintenance of working memory.

    • Grace E. Hallenbeck
    • , Thomas C. Sprague
    •  & Clayton E. Curtis
  • Article
    | Open Access

    Visual processing necessitates both extracting and discarding information. Here, the authors use a specialized set of stimuli and two complementary discrimination tasks to demonstrate the opposing perceptual implications of these two aspects of information processing.

    • Corey M. Ziemba
    •  & Eero P. Simoncelli
  • Article
    | Open Access

    Feedback modulates visual neurons, thought to help achieve flexible task performance. Here, the authors show decision-related feedback is not only relayed to task-relevant neurons, suggesting a broader mechanism and supporting a previously hypothesized link to feature-based attention.

    • Katrina R. Quinn
    • , Lenka Seillier
    •  & Hendrikje Nienborg
  • Article
    | Open Access

    The representation of space in mouse visual cortex was considered to be relatively uniform. The authors show that mice have improved visual resolution in a cortical region representing a location in space directly in front and slightly above them, showing that the representation of space in mouse visual cortex is non-uniform.

    • Enny H. van Beest
    • , Sreedeep Mukherjee
    •  & Matthew W. Self
  • Article
    | Open Access

    The gene regulatory network controlling the bifurcation of common progenitors into the neural retina and retinal-pigmented epithelium programs remains poorly understood. Here the authors study transcriptome dynamics and chromatin accessibility during this process in zebrafish, revealing network redundancy, as well as context-dependent and sequential transcription factor activity.

    • Lorena Buono
    • , Jorge Corbacho
    •  & Juan-Ramón Martínez-Morales
  • Article
    | Open Access

    The neural sampling theory suggests that neuronal variability encodes the uncertainty of probabilistic inferences. This paper shows that response variability in primary visual cortex reflects the statistical structure of visual inputs, as required for inferences correctly tuned to the statistics of the natural environment.

    • Dylan Festa
    • , Amir Aschner
    •  & Ruben Coen-Cagli
  • Article
    | Open Access

    Here, the authors show that the brain represents small and large numerosity ranges in a continuous topographic map, in line with the idea that differences in map properties underlie differences in perception.

    • Yuxuan Cai
    • , Shir Hofstetter
    •  & Serge O. Dumoulin
  • Article
    | Open Access

    Cortical and subcortical neural activity supporting conscious object recognition has not yet been well defined. Here, the authors describe these networks and show recognition-related category information can be decoded from widespread cortical activity but not subcortical activity.

    • Max Levinson
    • , Ella Podvalny
    •  & Biyu J. He
  • Article
    | Open Access

    Stimulus feature maps are found in primary visual cortex of many species. Here the authors show color maps in trichromatic primates containing segregated ensembles of neurons with distinct chromatic signatures that associate with cortical modules known as blobs.

    • Soumya Chatterjee
    • , Kenichi Ohki
    •  & R. Clay Reid
  • Article
    | Open Access

    Humans process faces using face-selective regions in the ventral and lateral streams which perform different tasks. Here, the authors show via functional and diffusion MRI that the spatial computations in face-selective regions vary across streams, constrained by connections from early visual areas.

    • Dawn Finzi
    • , Jesse Gomez
    •  & Kalanit Grill-Spector
  • Article
    | Open Access

    How intensely an individual focuses attention is a fundamental component of attention in improving behavior performance. Here, the authors isolated neuronal activity dynamics in visual cortex V4 that represents the intensive aspect of attention independent of selective attention and experimental covariates- reward expectation, motor response preparation.

    • Supriya Ghosh
    •  & John H. R. Maunsell
  • Article
    | Open Access

    This study shows that ganglion cells in mouse retina integrate chromatic visual signals either linearly or nonlinearly. Nonlinear chromatic integration depends on rod photoreceptor activity and on surround inhibition and may help detect chromatic boundaries, such as the skyline in natural scenes.

    • Mohammad Hossein Khani
    •  & Tim Gollisch
  • Article
    | Open Access

    Deep neural networks are widely considered as good models for biological vision. Here, we describe several qualitative similarities and differences in object representations between brains and deep networks that elucidate when deep networks can be considered good models for biological vision and how they can be improved.

    • Georgin Jacob
    • , R. T. Pramod
    •  & S. P. Arun
  • Article
    | Open Access

    Cholinergic neurons may transmit information via fast synaptic, point-to-point signaling or diffuse, slow extra-synaptic signaling. The authors show that ACh from a single vesicle triggers synchronous miniature currents in two neurons, showing that ACh can spread significant distances to drive rapid ‘synaptic’ signals.

    • Santhosh Sethuramanujam
    • , Akihiro Matsumoto
    •  & Gautam B. Awatramani
  • Article
    | Open Access

    Information regarding a sensory stimulus is distributed in activity of neuronal populations. Here the authors show stimulus information scales sub-linearly with the number of neurons in mouse visual cortex due to correlated noise and may saturate in far fewer numbers of neurons than the total in V1.

    • MohammadMehdi Kafashan
    • , Anna W. Jaffe
    •  & Jan Drugowitsch
  • Article
    | Open Access

    Identifying the frequency, temporal location, duration, and amplitude of finite oscillation packets in neurophysiological signals with high precision is challenging. The authors present a method based on multiple wavelets to improve the detection of localized time-frequency packets.

    • Vasile V. Moca
    • , Harald Bârzan
    •  & Raul C. Mureșan
  • Article
    | Open Access

    In the primate cortex, visual images are processed by multiple hierarchically-organized areas reciprocally connected via feedforward and feedback circuits. Here the authors show that feedback circuits are organized into segregated parallel streams that resemble feedforward pathways.

    • Frederick Federer
    • , Seminare Ta’afua
    •  & Alessandra Angelucci
  • Article
    | Open Access

    Two-photon imaging in macaque V1 captured maps of tuning selectivity for four spatial parameters, all of which correlated with peak spatial frequency. These inter-map relationships reveal a common motif—they are described by uniform spatial pooling from a family of scale invariant Gabor receptive fields.

    • Y. Chen
    • , H. Ko
    •  & I. Nauhaus
  • Article
    | Open Access

    Perceptually unidentifiable stimuli are encoded in the visual cortex, such as to facilitate their future processing in a task context. This form of priming may constitute a pre-attention mechanism using the mere frequency of stimulus occurrence to change stimulus representations, even when sensory inputs are perceptually invisible.

    • Sorin A. Pojoga
    • , Natasha Kharas
    •  & Valentin Dragoi
  • Article
    | Open Access

    In Old World primates, socially relevant face processing is accomplished via a distributed functional network including specialized patches in the frontal cortex. Here, the authors demonstrate a similar network in frontal cortex of New World marmoset monkeys, suggesting inheritance from a common ancestor.

    • David J. Schaeffer
    • , Janahan Selvanayagam
    •  & Stefan Everling
  • Article
    | Open Access

    To see during day and night, the retina adapts to a trillion-fold change in light intensity. The authors show that an accurate read-out of retinal signals over this intensity range requires that brain circuits account for changing noise correlations across populations of retinal neurons.

    • Kiersten Ruda
    • , Joel Zylberberg
    •  & Greg D. Field
  • Article
    | Open Access

    Progress in eye movement research has been limited since existing eye trackers are expensive and do not scale. Here, the authors show that smartphone-based eye tracking achieves high accuracy comparable to state-of-the-art mobile eye trackers, replicating key findings from prior eye movement research.

    • Nachiappan Valliappan
    • , Na Dai
    •  & Vidhya Navalpakkam
  • Article
    | Open Access

    The human brain is specialised for face processing, yet sometimes objects are perceived as illusory faces. Here, the authors show that illusory faces are initially represented similarly to real faces, but the representation quickly transforms into one equivalent to ordinary objects.

    • Susan G. Wardle
    • , Jessica Taubert
    •  & Chris I. Baker
  • Article
    | Open Access

    The orbitofrontal cortex (OFC) encodes expected outcomes and plays a key role in outcome-guided behavior. The authors show here that the top-down projection from the OFC to the visual cortex drives visual associative learning by modulating the response gain of V1 neurons to non-relevant stimuli.

    • Dechen Liu
    • , Juan Deng
    •  & Haishan Yao
  • Article
    | Open Access

    Sensory hypersensitivity is common in autism spectrum disorders. Using functional MRI, psychophysics, and computational modeling, Schallmo et al. show that differences in visual motion perception in ASD are accompanied by weaker neural suppression in visual cortex.

    • Michael-Paul Schallmo
    • , Tamar Kolodny
    •  & Scott O. Murray
  • Article
    | Open Access

    How does the brain represent sensory uncertainty? The authors find that neural gain variability tracks stimulus uncertainty across the visual hierarchy and explain their findings with a simple generalization of canonical models of neural computation.

    • Olivier J. Hénaff
    • , Zoe M. Boundy-Singer
    •  & Robbe L. T. Goris
  • Article
    | Open Access

    Neurons compute by integrating synaptic inputs across their dendritic arbor. Here, the authors show that distinct cell-types of mouse retinal ganglion cells that receive similar excitatory inputs have different biophysical mechanisms of input integration to generate their unique response tuning.

    • Yanli Ran
    • , Ziwei Huang
    •  & Thomas Euler
  • Article
    | Open Access

    Saccadic suppression is frequently attributed to active suppressive signals derived from eye movement commands. Here, the authors show that visual-only mechanisms starting in the retina can account for perceptual saccadic suppression properties without the need for motor-based suppression commands.

    • Saad Idrees
    • , Matthias P. Baumann
    •  & Ziad M. Hafed
  • Article
    | Open Access

    Visual cognition compensates for small changes in an object’s appearance to ensure its perceived continuity. We show that in situations with multiple objects, context features like color, temporal or spatial position are used as anchors to selectively integrate corresponding objects over time.

    • Cora Fischer
    • , Stefan Czoschke
    •  & Christoph Bledowski
  • Article
    | Open Access

    The visual callosal pathway reciprocally connects mammalian visual cortices and is proposed to facilitate activation of binocular neurons. Here, the authors show that this pathway facilitates responses in both monocular and binocular neurons but these responses are gated by the ipsilateral lateral geniculate nucleus.

    • Vishnudev Ramachandra
    • , Verena Pawlak
    •  & Jason N. D. Kerr
  • Article
    | Open Access

    Non-human primate models are important for the development of high quality vision restoration therapies for blindness. Here, the authors demonstrate restoration of light responses in foveal retinal ganglion cells of the living macaque following optogenetic gene therapy.

    • Juliette E. McGregor
    • , Tyler Godat
    •  & William H. Merigan