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Wang AYM, Kulkarni MM, McLaughlin AJ, Gayet J, Smith BE, Hauptschein M, McHugh CF, Yao YY, Puthussery T. An ON-type direction-selective ganglion cell in primate retina. Nature 2023; 623:381-386. [PMID: 37880369 PMCID: PMC10632142 DOI: 10.1038/s41586-023-06659-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 09/20/2023] [Indexed: 10/27/2023]
Abstract
To maintain a stable and clear image of the world, our eyes reflexively follow the direction in which a visual scene is moving. Such gaze-stabilization mechanisms reduce image blur as we move in the environment. In non-primate mammals, this behaviour is initiated by retinal output neurons called ON-type direction-selective ganglion cells (ON-DSGCs), which detect the direction of image motion and transmit signals to brainstem nuclei that drive compensatory eye movements1. However, ON-DSGCs have not yet been identified in the retina of primates, raising the possibility that this reflex is mediated by cortical visual areas. Here we mined single-cell RNA transcriptomic data from primate retina to identify a candidate ON-DSGC. We then combined two-photon calcium imaging, molecular identification and morphological analysis to reveal a population of ON-DSGCs in the macaque retina. The morphology, molecular signature and GABA (γ-aminobutyric acid)-dependent mechanisms that underlie direction selectivity in primate ON-DSGCs are highly conserved with those in other mammals. We further identify a candidate ON-DSGC in human retina. The presence of ON-DSGCs in primates highlights the need to examine the contribution of subcortical retinal mechanisms to normal and aberrant gaze stabilization in the developing and mature visual system.
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Affiliation(s)
- Anna Y M Wang
- Herbert Wertheim School of Optometry and Vision Science, Berkeley, CA, USA
- Helen Wills Neuroscience Institute, Berkeley, CA, USA
| | - Manoj M Kulkarni
- Herbert Wertheim School of Optometry and Vision Science, Berkeley, CA, USA
- Helen Wills Neuroscience Institute, Berkeley, CA, USA
| | - Amanda J McLaughlin
- Herbert Wertheim School of Optometry and Vision Science, Berkeley, CA, USA
- Helen Wills Neuroscience Institute, Berkeley, CA, USA
| | - Jacqueline Gayet
- Herbert Wertheim School of Optometry and Vision Science, Berkeley, CA, USA
- Helen Wills Neuroscience Institute, Berkeley, CA, USA
| | - Benjamin E Smith
- Herbert Wertheim School of Optometry and Vision Science, Berkeley, CA, USA
- Vision Science Graduate Program, University of California, Berkeley, Berkeley, CA, USA
| | - Max Hauptschein
- Herbert Wertheim School of Optometry and Vision Science, Berkeley, CA, USA
| | - Cyrus F McHugh
- Herbert Wertheim School of Optometry and Vision Science, Berkeley, CA, USA
- Vision Science Graduate Program, University of California, Berkeley, Berkeley, CA, USA
| | - Yvette Y Yao
- Herbert Wertheim School of Optometry and Vision Science, Berkeley, CA, USA
| | - Teresa Puthussery
- Herbert Wertheim School of Optometry and Vision Science, Berkeley, CA, USA.
- Helen Wills Neuroscience Institute, Berkeley, CA, USA.
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2
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In vivo chromatic and spatial tuning of foveolar retinal ganglion cells in Macaca fascicularis. PLoS One 2022; 17:e0278261. [PMID: 36445926 PMCID: PMC9707781 DOI: 10.1371/journal.pone.0278261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 11/13/2022] [Indexed: 11/30/2022] Open
Abstract
The primate fovea is specialized for high acuity chromatic vision, with the highest density of cone photoreceptors and a disproportionately large representation in visual cortex. The unique visual properties conferred by the fovea are conveyed to the brain by retinal ganglion cells, the somas of which lie at the margin of the foveal pit. Microelectrode recordings of these centermost retinal ganglion cells have been challenging due to the fragility of the fovea in the excised retina. Here we overcome this challenge by combining high resolution fluorescence adaptive optics ophthalmoscopy with calcium imaging to optically record functional responses of foveal retinal ganglion cells in the living eye. We use this approach to study the chromatic responses and spatial transfer functions of retinal ganglion cells using spatially uniform fields modulated in different directions in color space and monochromatic drifting gratings. We recorded from over 350 cells across three Macaca fascicularis primates over a time period of weeks to months. We find that the majority of the L vs. M cone opponent cells serving the most central foveolar cones have spatial transfer functions that peak at high spatial frequencies (20-40 c/deg), reflecting strong surround inhibition that sacrifices sensitivity at low spatial frequencies but preserves the transmission of fine detail in the retinal image. In addition, we fit to the drifting grating data a detailed model of how ganglion cell responses draw on the cone mosaic to derive receptive field properties of L vs. M cone opponent cells at the very center of the foveola. The fits are consistent with the hypothesis that foveal midget ganglion cells are specialized to preserve information at the resolution of the cone mosaic. By characterizing the functional properties of retinal ganglion cells in vivo through adaptive optics, we characterize the response characteristics of these cells in situ.
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3
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Patterson SS, Bembry BN, Mazzaferri MA, Neitz M, Rieke F, Soetedjo R, Neitz J. Conserved circuits for direction selectivity in the primate retina. Curr Biol 2022; 32:2529-2538.e4. [PMID: 35588744 DOI: 10.1016/j.cub.2022.04.056] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 02/25/2022] [Accepted: 04/20/2022] [Indexed: 02/06/2023]
Abstract
The detection of motion direction is a fundamental visual function and a classic model for neural computation. In the non-primate retina, direction selectivity arises in starburst amacrine cell (SAC) dendrites, which provide selective inhibition to direction-selective retinal ganglion cells (dsRGCs). Although SACs are present in primates, their connectivity and the existence of dsRGCs remain open questions. Here, we present a connectomic reconstruction of the primate ON SAC circuit from a serial electron microscopy volume of the macaque central retina. We show that the structural basis for the SACs' ability to confer directional selectivity on postsynaptic neurons is conserved. SACs selectively target a candidate homolog to the mammalian ON-sustained dsRGCs that project to the accessory optic system (AOS) and contribute to gaze-stabilizing reflexes. These results indicate that the capacity to compute motion direction is present in the retina, which is earlier in the primate visual system than classically thought.
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Affiliation(s)
- Sara S Patterson
- Center for Visual Science, University of Rochester, Rochester, NY 14620, USA; Department of Ophthalmology, University of Washington, Seattle, WA 98109, USA.
| | - Briyana N Bembry
- Department of Ophthalmology, University of Washington, Seattle, WA 98109, USA
| | - Marcus A Mazzaferri
- Department of Ophthalmology, University of Washington, Seattle, WA 98109, USA
| | - Maureen Neitz
- Department of Ophthalmology, University of Washington, Seattle, WA 98109, USA
| | - Fred Rieke
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195, USA
| | - Robijanto Soetedjo
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195, USA; Washington National Primate Research Center, University of Washington, Seattle, WA 98195, USA
| | - Jay Neitz
- Department of Ophthalmology, University of Washington, Seattle, WA 98109, USA.
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4
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Winkelman BHJ, Howlett MHC, Hölzel MB, Joling C, Fransen KH, Pangeni G, Kamermans S, Sakuta H, Noda M, Simonsz HJ, McCall MA, De Zeeuw CI, Kamermans M. Nystagmus in patients with congenital stationary night blindness (CSNB) originates from synchronously firing retinal ganglion cells. PLoS Biol 2019; 17:e3000174. [PMID: 31513577 PMCID: PMC6741852 DOI: 10.1371/journal.pbio.3000174] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 08/12/2019] [Indexed: 11/19/2022] Open
Abstract
Congenital nystagmus, involuntary oscillating small eye movements, is commonly thought to originate from aberrant interactions between brainstem nuclei and foveal cortical pathways. Here, we investigated whether nystagmus associated with congenital stationary night blindness (CSNB) results from primary deficits in the retina. We found that CSNB patients as well as an animal model (nob mice), both of which lacked functional nyctalopin protein (NYX, nyx) in ON bipolar cells (BCs) at their synapse with photoreceptors, showed oscillating eye movements at a frequency of 4-7 Hz. nob ON direction-selective ganglion cells (DSGCs), which detect global motion and project to the accessory optic system (AOS), oscillated with the same frequency as their eyes. In the dark, individual ganglion cells (GCs) oscillated asynchronously, but their oscillations became synchronized by light stimulation. Likewise, both patient and nob mice oscillating eye movements were only present in the light when contrast was present. Retinal pharmacological and genetic manipulations that blocked nob GC oscillations also eliminated their oscillating eye movements, and retinal pharmacological manipulations that reduced the oscillation frequency of nob GCs also reduced the oscillation frequency of their eye movements. We conclude that, in nob mice, synchronized oscillations of retinal GCs, most likely the ON-DCGCs, cause nystagmus with properties similar to those associated with CSNB in humans. These results show that the nob mouse is the first animal model for a form of congenital nystagmus, paving the way for development of therapeutic strategies.
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Affiliation(s)
- Beerend H. J. Winkelman
- Netherlands Institute for Neuroscience, Amsterdam, the Netherlands
- Department of Neuroscience, Erasmus MC, Rotterdam, the Netherlands
| | | | - Maj-Britt Hölzel
- Netherlands Institute for Neuroscience, Amsterdam, the Netherlands
| | - Coen Joling
- Netherlands Institute for Neuroscience, Amsterdam, the Netherlands
| | - Kathryn H. Fransen
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, Kentucky, United States of America
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky, United States of America
| | - Gobinda Pangeni
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, Kentucky, United States of America
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky, United States of America
| | | | - Hiraki Sakuta
- National Institute for Basic Biology, Okazaki, Japan
| | - Masaharu Noda
- National Institute for Basic Biology, Okazaki, Japan
| | - Huibert J. Simonsz
- Netherlands Institute for Neuroscience, Amsterdam, the Netherlands
- Department of Ophthalmology, Erasmus MC, Rotterdam, the Netherlands
| | - Maureen A. McCall
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, Kentucky, United States of America
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky, United States of America
| | - Chris I. De Zeeuw
- Netherlands Institute for Neuroscience, Amsterdam, the Netherlands
- Department of Neuroscience, Erasmus MC, Rotterdam, the Netherlands
| | - Maarten Kamermans
- Netherlands Institute for Neuroscience, Amsterdam, the Netherlands
- Department of Biomedical Physics, Academic Medical Center, University of Amsterdam, the Netherlands
- * E-mail:
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Abstract
The fovea dominates primate vision, and its anatomy and perceptual abilities are well studied, but its physiology has been little explored because of limitations of current physiological methods. In this study, we adapted a novel in vivo imaging method, originally developed in mouse retina, to explore foveal physiology in the macaque, which permits the repeated imaging of the functional response of many retinal ganglion cells (RGCs) simultaneously. A genetically encoded calcium indicator, G-CaMP5, was inserted into foveal RGCs, followed by calcium imaging of the displacement of foveal RGCs from their receptive fields, and their intensity-response functions. The spatial offset of foveal RGCs from their cone inputs makes this method especially appropriate for fovea by permitting imaging of RGC responses without excessive light adaptation of cones. This new method will permit the tracking of visual development, progression of retinal disease, or therapeutic interventions, such as insertion of visual prostheses.
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6
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Genetic dissection of retinal inputs to brainstem nuclei controlling image stabilization. J Neurosci 2013; 33:17797-813. [PMID: 24198370 DOI: 10.1523/jneurosci.2778-13.2013] [Citation(s) in RCA: 121] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
When the head rotates, the image of the visual world slips across the retina. A dedicated set of retinal ganglion cells (RGCs) and brainstem visual nuclei termed the "accessory optic system" (AOS) generate slip-compensating eye movements that stabilize visual images on the retina and improve visual performance. Which types of RGCs project to each of the various AOS nuclei remain unresolved. Here we report a new transgenic mouse line, Hoxd10-GFP, in which the RGCs projecting to all the AOS nuclei are fluorescently labeled. Electrophysiological recordings of Hoxd10-GFP RGCs revealed that they include all three subtypes of On direction-selective RGCs (On-DSGCs), responding to upward, downward, or forward motion. Hoxd10-GFP RGCs also include one subtype of On-Off DSGCs tuned for forward motion. Retrograde circuit mapping with modified rabies viruses revealed that the On-DSGCs project to the brainstem centers involved in both horizontal and vertical retinal slip compensation. In contrast, the On-Off DSGCs labeled in Hoxd10-GFP mice projected to AOS nuclei controlling horizontal but not vertical image stabilization. Moreover, the forward tuned On-Off DSGCs appear physiologically and molecularly distinct from all previously genetically identified On-Off DSGCs. These data begin to clarify the cell types and circuits underlying image stabilization during self-motion, and they support an unexpected diversity of DSGC subtypes.
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7
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Abstract
The review deals with the morphology, physiology, topography, and central projections of direction-selective cells of the accessory optic system in vertebrates.
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Affiliation(s)
- Igor I Pushchin
- Laboratory of Physiology, A. V. Zhirmunsky Institute of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok 690059, Russia
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8
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Abstract
The horizontal optokinetic nystagmus (hOKN) in primates is immature at birth. To elucidate the early functional state of the visual pathway for hOKN, retinal slip neurons were recorded in the nucleus of the optic tract and dorsal terminal nucleus (NOT-DTN) of 4 anesthetized infant macaques. These neurons were direction selective for ipsiversive stimulus movement shortly after birth [postnatal day 9 (P9)], although at a lower direction selectivity index (DSI). The DSI in the older infants (P12, P14, P60) was not different from adults. A total of 96% of NOT-DTN neurons in P9, P12, and P14 were binocular, however, significantly more often dominated by the contralateral eye than in adults. Already in the youngest animals, NOT-DTN neurons were well tuned to different stimulus velocities; however, tuning was truncated toward lower stimulus velocities when compared with adults. As early as at P12, electrical stimulation in V1 elicited orthodromic responses in the NOT-DTN. However, the incidence of activated neurons was much lower in infants (40-60% of the tested NOT-DTN neurons) than in adults (97%). Orthodromic latencies from V1 were significantly longer in P12-P14 (x = 12.2 ± 8.9 ms) than in adults (x = 3.51 ± 0.81 ms). At the same age, electrical stimulation in motion-sensitive area MT was more efficient in activating NOT-DTN neurons (80% of the tested cells) and yielded shorter latencies than in V1 (x = 7.8 ± 3.02 ms; adult x = 2.99 ± 0.85 ms). The differences in discharge rate between neurons in the NOT-DTN contra- and ipsilateral to the stimulated eye are equivalent to the gain asymmetry between monocularly elicited OKN in temporonasal and nasotemporal direction at the various ages.
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9
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Borst A, Euler T. Seeing Things in Motion: Models, Circuits, and Mechanisms. Neuron 2011; 71:974-94. [PMID: 21943597 DOI: 10.1016/j.neuron.2011.08.031] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2011] [Indexed: 12/31/2022]
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10
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Seno T, Ito H, Sunaga S, Nakamura S. Temporonasal motion projected on the nasal retina underlies expansion–contraction asymmetry in vection. Vision Res 2010; 50:1131-9. [DOI: 10.1016/j.visres.2010.03.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Revised: 03/19/2010] [Accepted: 03/26/2010] [Indexed: 11/29/2022]
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11
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Dobkins KR, Sampath V. The use of chromatic information for motion segmentation: differences between psychophysical and eye-movement measures. Perception 2008; 37:993-1009. [PMID: 18773723 DOI: 10.1068/p5957] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Previous psychophysical studies have shown that chromatic (red/green) information can be used as a segmentation cue for motion integration. We investigated the mechanisms mediating this phenomenon by comparing chromatic effects (and, for comparison, luminance effects) on motion integration between two measures: (i) directional eye movements with the notion that these responses are mediated mainly by low-level motion mechanisms, and (ii) psychophysical reports, with the notion that subjects' reports should employ higher-level (attention-based) mechanisms if available. To quantify chromatic (and luminance) effects on motion integration, coherent motion thresholds were obtained for two conditions, one in which the signal and noise dots were the same 'red' or 'green' chromaticity (or the same 'bright' or 'dark' luminance), referred to as homogeneous, and the other in which the signal and noise dots were of different chromaticities (or luminances), referred to as heterogeneous. 'Benefit ratios' (theta(HOM)/theta(HET)) were then computed, with values significantly greater than 1.0 indicating that chromatic (or luminance) information serves as a segmentation cue for motion integration. The results revealed a high and significant chromatic benefit ratio when the measure was based on psychophysical report, but not when it was based on an eye-movement measure. By contrast, luminance benefit ratios were roughly the same (and significant) for both measures. For comparison to adults, eye-movement data were also obtained from 3-month-old infants. Infants showed marginally significant benefit ratios in the luminance, but not in the chromatic, condition. In total, these results suggest that the use of chromatic information as a segmentation cue for motion integration relies on higher-level mechanisms, whereas luminance information works mainly through low-level motion mechanisms.
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Affiliation(s)
- Karen R Dobkins
- Department of Psychology, University of California, San Diego, La Jolla, CA 92093, USA.
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12
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Engelberth RCGJ, de Pontes ALB, do Nascimento RBS, de Lima RRM, de Lima RR, de Toledo CAB, de Oliveira Costa MSM, Britto LRG, de Souza Cavalcante J. Discrete retinal input to the parabrachial complex of a new-world primate, the common marmoset (Callithrix jacchus). Neurosci Lett 2008; 443:99-103. [DOI: 10.1016/j.neulet.2008.07.065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2008] [Revised: 07/12/2008] [Accepted: 07/25/2008] [Indexed: 10/21/2022]
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13
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Seno T, Sato T. Positional and directional preponderances in vection. Exp Brain Res 2008; 192:221-9. [DOI: 10.1007/s00221-008-1575-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2007] [Accepted: 09/08/2008] [Indexed: 10/21/2022]
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Abstract
In macaque monkeys, an optokinetic response (OKR) can be elicited monocularly both in temporonasal and, albeit weaker, in nasotemporal direction very early after birth. The further maturation of equal strengths of OKR in both directions depends on stimulus velocity: at low-stimulus velocities (10-20 degrees /s) symmetry is reached at 3-4 weeks of age, at higher-stimulus velocities (40-80 degrees /s) it is reached only at 4-5 months of age. Retinal slip neurons in the NOT-DTN are direction selective for ipsiversive stimulus movement shortly after birth. Most of these neurons receive input from both eyes; many are dominated by the contralateral eye. Electrophysiological and neuroanatomical evidence suggests that the cortical input to the NOT-DTN starts to become functional by postnatal day 14, at the latest. Based on these behavioral and physiological data, as well as on comparison with data from kittens and human infants, we hypothesize that the very early monocularly elicited bidirectional optokinetic response is due to the direct retinal input from both eyes to the NOT-DTN. As the cortical projection matures, it gains more and more influence upon the response properties of retinal slip neurons in the NOT-DTN, and the retinal influence gradually decreases.
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Affiliation(s)
- C Distler
- Allgemeine Zoologie Neurobiologie, Ruhr-Universität Bochum, D-44780 Bochum, Germany.
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15
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Abstract
Research over the past two decades in mammals, especially primates, has greatly improved our understanding of the afferent and efferent connections of two retinorecipient pretectal nuclei, the nucleus of the optic tract (NOT) and the pretectal olivary nucleus (PON). Functional studies of these two nuclei have further elucidated some of the roles that they play both in oculomotor control and in relaying oculomotor-related signals to visual relay nuclei. Therefore, following a brief overview of the anatomy and retinal projections to the entire mammalian pretectum, the connections and potential roles of the NOT and the PON are considered in detail. Data on the specific connections of the NOT are combined with data from single-unit recording, microstimulation, and lesion studies to show that this nucleus plays critical roles in optokinetic nystagmus, short-latency ocular following, smooth pursuit eye movements, and adaptation of the gain of the horizontal vestibulo-ocular reflex. Comparable data for the PON show that this nucleus plays critical roles in the pupillary light reflex, light-evoked blinks, rapid eye movement sleep triggering, and modulating subcortical nuclei involved in circadian rhythms.
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Affiliation(s)
- Paul D R Gamlin
- Department of Vision Sciences, School of Optometry, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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16
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Ibbotson MR. Contrast and Temporal Frequency-Related Adaptation in the Pretectal Nucleus of the Optic Tract. J Neurophysiol 2005; 94:136-46. [PMID: 15728765 DOI: 10.1152/jn.00980.2004] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In mammals, many cells in the retino-geniculate-cortical pathway adapt during stimulation with high contrast gratings. In the visual cortex, adaptation to high contrast images reduces sensitivity at low contrasts while only moderately affecting sensitivity at high contrasts, thus generating rightward shifts in the contrast response functions (contrast gain control). Similarly, motion adaptation at particular temporal frequencies (TFs) alters the temporal tuning properties of cortical cells. For the first time in any species, this paper investigates the influence of motion adaptation on both the contrast and TF responses of neurons in the retino-pretectal pathway by recording from direction-selective neurons in the nucleus of the optic tract (NOT) of the marsupial wallaby, Macropus eugenii. This species is of interest because its NOT receives almost all input directly from the retina, with virtually none from the visual cortex (unlike cats and primates). All NOT cells show changes in their contrast response functions after adaptation, many revealing contrast gain control. Contrast adaptation is direction-dependent, preferred directions producing the largest changes. The lack of cortical input suggests that contrast adaptation is generated independently from the cortex in the NOT or retina. Motion adaptation also produces direction-selective effects on the TF tuning of NOT neurons by shifting the location of the optimum TF. Cells that show strong adaptation to contrast also tend to show large changes in TF tuning, suggesting similar intracellular mechanisms. The data are discussed in terms of the generality of contrast adaptation across mammalian species and across unconnected brain regions within the same species.
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Affiliation(s)
- M R Ibbotson
- Visual Sciences, Research School of Biological Sciences, Australian National University, Canverra, Australia.
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17
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Clifford CWG, Ibbotson MR. Fundamental mechanisms of visual motion detection: models, cells and functions. Prog Neurobiol 2002; 68:409-37. [PMID: 12576294 DOI: 10.1016/s0301-0082(02)00154-5] [Citation(s) in RCA: 140] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Taking a comparative approach, data from a range of visual species are discussed in the context of ideas about mechanisms of motion detection. The cellular basis of motion detection in the vertebrate retina, sub-cortical structures and visual cortex is reviewed alongside that of the insect optic lobes. Special care is taken to relate concepts from theoretical models to the neural circuitry in biological systems. Motion detection involves spatiotemporal pre-filters, temporal delay filters and non-linear interactions. A number of different types of non-linear mechanism such as facilitation, inhibition and division have been proposed to underlie direction selectivity. The resulting direction-selective mechanisms can be combined to produce speed-tuned motion detectors. Motion detection is a dynamic process with adaptation as a fundamental property. The behavior of adaptive mechanisms in motion detection is discussed, focusing on the informational basis of motion adaptation, its phenomenology in human vision, and its cellular basis. The question of whether motion adaptation serves a function or is simply the result of neural fatigue is critically addressed.
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Affiliation(s)
- C W G Clifford
- Colour, Form and Motion Laboratory, Visual Perception Unit, School of Psychology, The University of Sydney, Sydney 2006, NSW, Australia.
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18
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Hoffmann KP, Bremmer F, Thiele A, Distler C. Directional asymmetry of neurons in cortical areas MT and MST projecting to the NOT-DTN in macaques. J Neurophysiol 2002; 87:2113-23. [PMID: 11929929 DOI: 10.1152/jn.00488.2001] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The cortical projection to the subcortical pathway underlying the optokinetic reflex was studied using antidromic electrical stimulation in the midbrain structures nucleus of the optic tract and dorsal terminal nucleus of the accessory optic system (NOT-DTN) while simultaneously recording from cortical neurons in the superior temporal sulcus (STS) of macaque monkeys. Projection neurons were found in all subregions of the middle temporal area (MT) as well as in the medial superior temporal area (MST). Antidromic latencies ranged from 0.9 to 6 ms with a median of 1.8 ms. There was a strong bias in the population of cortical neurons projecting to the NOT-DTN for ipsiversive stimulus movement (towards the recording side), whereas in the population of cortical neurons not projecting to the NOT-DTN a more or less equal distribution of stimulus directions was evident. Our data indicate that there is no special area in the posterior STS coding for ipsiversive horizontal stimulus movement. Instead, a specific selection of cortical neurons from areas MT and MST forms the projection to the NOT-DTN and as a subpopulation has the same directional bias as their subcortical target neurons. These findings are discussed in relation to the functional grouping of cortical output as an organizational principle for specific motor responses.
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Affiliation(s)
- K-P Hoffmann
- Allgemeine Zoologie and Neurobiologie, Ruhr-Universität Bochum, D-44780 Bochum, Germany.
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