Annual Review of Vision Science最新文献

Inferences made about objects via vision, such as rapid and accurate categorization, are core to primate cognition despite the algorithmic challenge posed by varying viewpoints and scenes. Until recently, the brain mechanisms that support these capabilities were deeply mysterious. However, over the past decade, this scientific mystery has been illuminated by the discovery and development of brain-inspired, image-computable, artificial neural network (ANN) systems that rival primates in these behavioral feats. Apart from fundamentally changing the landscape of artificial intelligence, modified versions of these ANN systems are the current leading scientific hypotheses of an integrated set of mechanisms in the primate ventral visual stream that support core object recognition. What separates brain-mapped versions of these systems from prior conceptual models is that they are sensory computable, mechanistic, anatomically referenced, and testable (SMART). In this article, we review and provide perspective on the brain mechanisms addressed by the current leading SMART models. We review their empirical brain and behavioral alignment successes and failures, discuss the next frontiers for an even more accurate mechanistic understanding, and outline the likely applications.

Carotenoids, yellow and red pigments found abundantly in nature, play essential roles in various aspects of human physiology. They serve as critical molecules in vision by functioning as antioxidants and as filters for blue light within the retina. Furthermore, carotenoids are the natural precursors of vitamin A, which is indispensable for the synthesis of retinaldehyde, the visual chromophore, and retinoic acid, a small molecule that regulates gene expression. Insufficient levels of carotenoids and retinoids have been linked to age-related macular degeneration and xerophthalmia, respectively. Nevertheless, the mechanisms by which the eye maintains carotenoid and retinoid homeostasis have remained a mystery. Recent breakthroughs identified the molecular players involved in this process and provided valuable biochemical insights into their functioning. Mutations in the corresponding genes disrupt the homeostasis of carotenoids and retinoids, leading to visual system pathologies. This review aims to consolidate our current understanding of these pathways, including their regulatory principles.

The continuous function of vertebrate photoreceptors requires regeneration of their visual pigment following its destruction upon activation by light (photobleaching). For rods, the chromophore required for the regeneration of rhodopsin is derived from the adjacent retinal pigmented epithelium (RPE) cells through a series of reactions collectively known as the RPE visual cycle. Mounting biochemical and functional evidence demonstrates that, for cones, pigment regeneration is supported by the parallel supply with chromophore by two pathways-the canonical RPE visual cycle and a second, cone-specific retina visual cycle that involves the Müller glial cells in the neural retina. In this article, we review historical information that led to the discovery of the retina visual cycle and discuss what is currently known about the reactions and molecular components of this pathway and its functional role in supporting cone-mediated vision.

Central serous chorioretinopathy (CSCR) is the fourth most common medical retinal disease. Moderate vision loss occurs in approximately one-third of patients who have the chronic form of the disease. CSCR has a multifactorial etiology, with acquired risk factors and increasing evidence of genetic susceptibility factors. The detection of new gene variants in CSCR and association of these variants with age-related macular degeneration provide insights into possible disease mechanisms. The contribution of multimodal ocular imaging and associated research studies to the modern-day clinical investigation of CSCR has been significant. This review aims to provide an overview of the most significant epidemiological and genetic studies of CSCR, in addition to describing its clinical and multimodal imaging features. The review also provides an update of the latest evidence from studies investigating pathophysiological mechanisms in CSCR and current opinions on multimodal imaging to better classify this complex retinal disease.

The study of biological optics would be complicated enough if light only came in a single wavelength. However, altering the wavelength (or distribution of wavelengths) of light has multiple effects on optics, including on diffraction, scattering (of various sorts), transmission through and reflection by various media, fluorescence, and waveguiding properties, among others. In this review, we consider just one wavelength-dependent optical effect: longitudinal chromatic aberration (LCA). All vertebrate eyes that have been tested have significant LCA, with shorter (bluer) wavelengths of light focusing closer to the front of the eye than longer (redder) wavelengths. We consider the role of LCA in the visual system in terms of both how it could degrade visual acuity and how biological systems make use of it.

Animals live in visually complex environments. As a result, visual systems have evolved mechanisms that simplify visual processing and allow animals to focus on the information that is most relevant to adaptive decision making. This review explores two key mechanisms that animals use to efficiently process visual information: categorization and specialization. Categorization occurs when an animal's perceptual system sorts continuously varying stimuli into a set of discrete categories. Specialization occurs when particular classes of stimuli are processed using distinct cognitive operations that are not used for other classes of stimuli. We also describe a nonadaptive consequence of simplifying heuristics: visual illusions, where visual perception consistently misleads the viewer about the state of the external world or objects within it. We take an explicitly comparative approach by exploring similarities and differences in visual cognition across human and nonhuman taxa. Considering areas of convergence and divergence across taxa provides insight into the evolution and function of visual systems and associated perceptual strategies.

Our visual systems are remarkably adept at deriving the shape and material properties of surfaces even when only one image of a surface is available. This ability implies that a single image of a surface contains potent information about both surface shape and material. However, from a computational perspective, the problem of deriving surface shape and material is formally ill posed. Any given image could be due to many combinations of shape, material, and illumination. Early computational models required prior knowledge about two of the three scene variables to derive the third. However, such models are biologically implausible because our visual systems are tasked with extracting all relevant scene variables from images simultaneously. This review describes recent progress in understanding how the visual system solves this problem by identifying complex forms of image structure that support its ability to simultaneously derive the shape and material properties of surfaces from images.

The ventral visual pathway transforms retinal images into neural representations that support object understanding, including exquisite appreciation of precise 2D pattern shape and 3D volumetric shape. We articulate a framework for understanding the goals of this transformation and how they are achieved by neural coding at successive ventral pathway stages. The critical goals are (a) radical compression to make shape information communicable across axonal bundles and storable in memory, (b) explicit coding to make shape information easily readable by the rest of the brain and thus accessible for cognition and behavioral control, and (c) representational stability to maintain consistent perception across highly variable viewing conditions. We describe how each transformational step in ventral pathway vision serves one or more of these goals. This three-goal framework unifies discoveries about ventral shape processing into a neural explanation for our remarkable experience of shape as a vivid, richly detailed aspect of the natural world.