Asymmetries in the Architecture of ON and OFF Arbors in ON–OFF Direction‐Selective Ganglion Cells

The Journal of Comparative Neurology, Год журнала: 2025, Номер 533(1)

Опубликована: Янв. 1, 2025

ABSTRACT Direction selectivity is a fundamental feature in the visual system. In retina, direction independently computed by ON and OFF circuits. However, advantages of extracting directional information from these two independent circuits are unclear. To gain insights, we examined ON–OFF direction‐selective ganglion cells (DSGCs), which recombine signals both Specifically, investigated dendritic architecture neurons with premise that asymmetries will provide insights into function. Scrutinizing dendrites dye‐filled DSGCs reveals arbors substantially denser. The increase density can be primarily attributed to higher branching seen arbors. Further, analysis previously published serial block‐face electron microscopy dataset revealed denser packed more bipolar synapses per unit length. These suggest DSGC preferentially magnifies synaptic drive pathway, potentially allowing it encode distinct pathway.

Язык: Английский

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Distinct inhibitory pathways control velocity and directional tuning in the mouse retina

Current Biology, Год журнала: 2022, Номер 32(10), С. 2130 - 2143.e3

Опубликована: Апрель 7, 2022

The sensory periphery is responsible for detecting ethologically relevant features of the external world, using compact, predominantly feedforward circuits. Visual motion a particularly prevalent feature, presence which can be signal to enact diverse behaviors ranging from gaze stabilization reflexes predator avoidance or prey capture. To understand how retina constructs distinct neural representations required these behaviors, we investigated two circuits encoding different aspects image motion: ON and ON-OFF direction-selective ganglion cells (DSGCs). Using combination two-photon targeted whole-cell electrophysiology, pharmacology, conditional knockout mice, show that inhibitory pathways independently control tuning velocity direction in cell types. We further employ dynamic clamp numerical modeling techniques asymmetric inhibition provides velocity-invariant mechanism directional tuning, despite strong dependence classical models selectivity. therefore demonstrate invariant by interneurons act as computational building blocks construct distinct, behaviorally signals at earliest stages visual system.

Язык: Английский

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A Novel Artificial Visual System for Motion Direction Detection with Completely Modeled Retinal Direction-Selective Pathway

Mathematics, Год журнала: 2023, Номер 11(17), С. 3732 - 3732

Опубликована: Авг. 30, 2023

Some fundamental visual features have been found to be fully extracted before reaching the cerebral cortex. We focus on direction-selective ganglion cells (DSGCs), which exist at terminal end of retinal pathway, forefront system. By utilizing a layered pathway composed various relevant in early stage retina, DSGCs can extract multiple motion directions occurring field. However, despite considerable amount comprehensive research (from structures), definitive conclusion explaining specific details underlying mechanisms has not reached. In this paper, leveraging some important conclusions from neuroscience research, we propose complete quantified model for direction selection and elucidate global information acquisition mechanism cortex using simple spiking neural mechanism. This is referred as artificial system (AVS). conduct extensive testing, including one million sets two-dimensional eight-directional binary object instances with 10 different sizes random shapes. also evaluate AVS’s noise resistance generalization performance by introducing static dynamic noises. Furthermore, thoroughly validate efficiency, compare its two state-of-the-art deep learning algorithms (LeNet-5 EfficientNetB0) all tests. The experimental results demonstrate that due highly biomimetic design characteristics, AVS exhibits outstanding detection. Additionally, possesses computing advantages terms hardware implementation, difficulty, parameter quantity.

Язык: Английский

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Emergence of synaptic organization and computation in dendrites

Neuroforum, Год журнала: 2021, Номер 28(1), С. 21 - 30

Опубликована: Дек. 30, 2021

Abstract Single neurons in the brain exhibit astounding computational capabilities, which gradually emerge throughout development and enable them to become integrated into complex neural circuits. These capabilities derive part from precise arrangement of synaptic inputs on neurons’ dendrites. While full benefits this are still unknown, a picture emerges synapses organize according their functional properties across multiple spatial scales. In particular, local scale (tens microns), excitatory tend form clusters similarity, whereas individual dendrites or entire tree, dendritic maps where synapse function varies smoothly with location tree. The organization is supported by inhibitory synapses, carefully interleaved can flexibly modulate activity plasticity synapses. Here, we summarize recent experimental theoretical research developmental emergence its impact computations.

Язык: Английский

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Molecular identification of wide-field amacrine cells in mouse retina that encode stimulus orientation

Опубликована: Фев. 26, 2024

Visual information processing is sculpted by a diverse group of inhibitory interneurons in the retina called amacrine cells. Yet, for most >60 cell types, molecular identities and specialized functional attributes remain elusive. Here, we developed an intersectional genetic strategy to target wide-field cells (WACs) mouse that co-express transcription factor Bhlhe22 Kappa Opioid Receptor (KOR; B/K WACs). WACs feature straight, unbranched dendrites spanning over 0.5 mm (∼15° visual angle) produce non-spiking responses either light increments or decrements. Two-photon dendritic population imaging reveals Ca 2+ signals tuned physical orientations WAC dendrites, signifying robust structure-function alignment. establish divergent connections with multiple retinal neurons, including unexpected non-orientation-tuned ganglion bipolar Our work sets stage future comprehensive investigations enigmatic neurons: WACs.

Язык: Английский

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Receptoral Mechanisms for Fast Cholinergic Transmission in Direction-Selective Retinal Circuitry

Frontiers in Cellular Neuroscience, Год журнала: 2020, Номер 14

Опубликована: Ноя. 26, 2020

Direction selectivity represents an elementary sensory computation that can be related to underlying synaptic mechanisms. In mammalian retina, direction-selective ganglion cells (DSGCs) respond strongly visual motion in a “preferred” direction and weakly the opposite, “null” direction. The DS mechanism depends on starburst amacrine (SACs), which provide null direction-tuned GABAergic inhibition untuned cholinergic excitation DSGCs. conventional transmission, whereas apparently paracrine (i.e., non-synaptic) transmission. Despite its mode of is more transient than inhibition, yielding temporal difference contributes essentially computation. To isolate mechanisms generate distinct properties transmission from SACs DSGCs, we optogenetically stimulated while recording postsynaptic currents (PSCs) DSGCs mouse retina. Direct recordings channelrhodopsin-2-expressing (ChR2 + ) during quasi-white noise (WN) (0-30 Hz) photostimulation demonstrated precise, graded optogenetic control SAC membrane current potential. Linear systems analysis ChR2-evoked PSCs recorded revealed faster A deconvolution-based showed receptor kinetics fully account for between Furthermore, GABA blockade prolonged identifying new functional role SACs. Thus, fast arises at least two mechanisms, consistent with synapses despite nature.

Язык: Английский

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Parallel processing in active dendrites during periods of intense spiking activity

Cell Reports, Год журнала: 2022, Номер 38(8), С. 110412 - 110412

Опубликована: Фев. 1, 2022

A neuron's ability to perform parallel computations throughout its dendritic arbor substantially improves computational capacity. However, during natural patterns of activity, the degree which remain compartmentalized, especially in neurons with active trees, is not clear. Here, we examine how direction moving objects computed across bistratified arbors ON-OFF direction-selective ganglion cells (DSGCs) mouse retina. We find that although local synaptic signals propagate efficiently their one part have little effect on those being made elsewhere. Independent processing allows DSGCs compute multiple times as they traverse receptive fields, enabling them rapidly detect changes motion a sub-receptive-field basis. These results demonstrate capacity can be maintained even periods intense activity.

Язык: Английский

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Mechanism of Motion Direction Detection Based on Barlow’s Retina Inhibitory Scheme in Direction-Selective Ganglion Cells

Electronics, Год журнала: 2021, Номер 10(14), С. 1663 - 1663

Опубликована: Июль 13, 2021

Previous studies have reported that directionally selective ganglion cells respond strongly in their preferred direction, but are only weakly excited by stimuli moving the opposite null direction. Various attempted to elucidate mechanisms underlying direction selectivity with cellular basis. However, these not elucidated mechanism motion detection. In this study, we propose based on Barlow’s inhibitory scheme for We described local motion-sensing direction-selective neurons. Next, model was used construct two-dimensional multi-directional detection neurons which detect directions. The information of directions finally infer global To verify validity proposed mechanism, conducted a series experiments involving dataset number images. exhibited good performance all high accuracy. Furthermore, compare our system and traditional Convolution Neural Network (CNN) prediction. It is found much better than CNN terms accuracy, calculation speed cost.

Язык: Английский

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Molecular identification of wide-field amacrine cells in mouse retina that encode stimulus orientation

Опубликована: Фев. 26, 2024

Visual information processing is sculpted by a diverse group of inhibitory interneurons in the retina called amacrine cells. Yet, for most >60 cell types, molecular identities and specialized functional attributes remain elusive. Here, we developed an intersectional genetic strategy to target wide-field cells (WACs) mouse that co-express transcription factor Bhlhe22 Kappa Opioid Receptor (KOR; B/K WACs). WACs feature straight, unbranched dendrites spanning over 0.5 mm (∼15° visual angle) produce non-spiking responses either light increments or decrements. Two-photon dendritic population imaging reveals Ca 2+ signals tuned physical orientations WAC dendrites, signifying robust structure-function alignment. establish divergent connections with multiple retinal neurons, including unexpected non-orientation-tuned ganglion bipolar Our work sets stage future comprehensive investigations enigmatic neurons: WACs.

Язык: Английский

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Light-evoked dendritic spikes in sustained but not transient rabbit retinal ganglion cells

Neuron, Год журнала: 2022, Номер 110(17), С. 2802 - 2814.e3

Опубликована: Июль 7, 2022

Dendritic computations have a central role in neuronal function, but it is unknown how cell-class heterogeneity of dendritic electrical excitability shapes physiologically engaged and circuit computations. To address this, we examined integration closely related classes retinal ganglion cells (GCs) using simultaneous somato-dendritic recording techniques functionally intact circuit. Simultaneous recordings revealed sustained OFF-GCs generated powerful spikes response to visual input that drove action potential firing. In contrast, the dendrites transient were passive did not generate spikes. spike generation allowed sustained, transient, signal into output local motion stimuli produce continuous wave firing adjacent as images moved across retina. Conversely, this representation was highly fragmented OFF-GCs. Thus, defines executed by GCs.

Язык: Английский

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