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Book ; Conference proceedings: Dynamics of the outer retina

Kamermans, Maarten

[satellite symposium of the meeting of the European Neuroscience Association (ENA) held in Amsterdam, The Netherlands, 1 - 2 September 1995 ; Symposium Entitled the Dynamics of the Outer Retina]

(Vision research ; 36,24 : Special issue)

1996

Institution	Symposium Entitled the Dynamics of the Outer Retina European Neuroscience Association
Author's details	[guest eds.: Maarten Kamermans ...]
Series title	Vision research ; 36,24 : Special issue
Keywords	Retina / physiology / congresses ; Receptors, GABA / physiology / congresses ; Photoreceptors / physiology / congresses ; Vertebrates / physiology / congresses
Language	English
Size	S. 3857 - 4125 : Ill., graph. Darst.
Publisher	Pergamon u.a.
Publishing place	Oxford
Publishing country	Great Britain
Document type	Book ; Conference proceedings
HBZ-ID	HT007384572
Database	Catalogue ZB MED Medicine, Health

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Article ; Online: Receptive Field Sizes of

Hölzel, Maj-Britt / Howlett, Marcus H C / Kamermans, Maarten

International journal of molecular sciences

2022 Volume 23, Issue 6

Abstract: Patients with congenital nystagmus, involuntary eye movements, often have a reduced visual acuity. Some of these patients have a retinal-specific mutation in the protein nyctalopin, which is also present in ... ...

Abstract	Patients with congenital nystagmus, involuntary eye movements, often have a reduced visual acuity. Some of these patients have a retinal-specific mutation in the protein nyctalopin, which is also present in the
MeSH term(s)	Animals ; Humans ; Mice ; Mice, Inbred C57BL ; Proteoglycans/genetics ; Retina ; Retinal Ganglion Cells
Chemical Substances	NYX protein, human ; Proteoglycans
Language	English
Publishing date	2022-03-16
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2019364-6
ISSN	1422-0067 ; 1422-0067 ; 1661-6596
ISSN (online)	1422-0067
ISSN	1422-0067 ; 1661-6596
DOI	10.3390/ijms23063202
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Article ; Online: Change the neural code, change the message.

Kamermans, Maarten

Nature neuroscience

2015 Volume 18, Issue 1, Page(s) 4–6

MeSH term(s)	Animals ; Humans ; Lighting ; Neural Inhibition/physiology ; Photic Stimulation/methods ; Retina/physiology ; Retinal Cone Photoreceptor Cells/physiology ; Retinal Horizontal Cells/physiology ; Retinal Rod Photoreceptor Cells/physiology
Language	English
Publishing date	2015-01
Publishing country	United States
Document type	Comment ; News
ZDB-ID	1420596-8
ISSN	1546-1726 ; 1097-6256
ISSN (online)	1546-1726
ISSN	1097-6256
DOI	10.1038/nn.3899
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Article ; Online: Enhancing the dark side: asymmetric gain of cone photoreceptors underpins their discrimination of visual scenes based on skewness.

Yedutenko, Matthew / Howlett, Marcus H C / Kamermans, Maarten

The Journal of physiology

2021 Volume 600, Issue 1, Page(s) 123–142

Abstract: Psychophysical data indicate that humans can discriminate visual scenes based on their skewness, i.e. the ratio of dark and bright patches within a visual scene. It has also been shown that at a phenomenological level this skew discrimination is ... ...

Abstract	Psychophysical data indicate that humans can discriminate visual scenes based on their skewness, i.e. the ratio of dark and bright patches within a visual scene. It has also been shown that at a phenomenological level this skew discrimination is described by the so-called blackshot mechanism, which accentuates strong negative contrasts within a scene. Here, we present a set of observations suggesting that the underlying computation might start as early as the cone phototransduction cascade, whose gain is higher for strong negative contrasts than for strong positive contrasts. We recorded from goldfish cone photoreceptors and found that the asymmetry in the phototransduction gain leads to responses with larger amplitudes when using negatively rather than positively skewed light stimuli. This asymmetry in amplitude was present in the cone photocurrent, voltage response and synaptic output. Given that the properties of the phototransduction cascade are universal across vertebrates, it is possible that the mechanism shown here gives rise to a general ability to discriminate between scenes based only on their skewness, which psychophysical studies have shown humans can do. Thus, our data suggest the importance of non-linearity of the early photoreceptor for perception. Additionally, we found that stimulus skewness leads to a subtle change in photoreceptor kinetics. For negatively skewed stimuli, the impulse response functions of the cone peak later than for positively skewed stimuli. However, stimulus skewness does not affect the overall integration time of the cone. KEY POINTS: Humans can discriminate visual scenes based on skewness, i.e. the relative prevalence of bright and dark patches within a scene. Here, we show that negatively skewed time-series stimuli induce larger responses in goldfish cone photoreceptors than comparable positively skewed stimuli. This response asymmetry originates from within the phototransduction cascade, where gain is higher for strong negative contrasts (dark patches) than for strong positive contrasts (bright patches). Unlike the implicit assumption often contained within models of downstream visual neurons, our data show that cone photoreceptors do not simply relay linearly filtered versions of visual stimuli to downstream circuitry, but that they also emphasize specific stimulus features. Given that the phototransduction cascade properties among vertebrate retinas are mostly universal, our data imply that the skew discrimination by human subjects reported in psychophysical studies might stem from the asymmetric gain function of the phototransduction cascade.
MeSH term(s)	Animals ; Goldfish ; Humans ; Retina ; Retinal Cone Photoreceptor Cells
Language	English
Publishing date	2021-12-08
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	3115-x
ISSN	1469-7793 ; 0022-3751
ISSN (online)	1469-7793
ISSN	0022-3751
DOI	10.1113/JP282152
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Article: High Contrast Allows the Retina to Compute More Than Just Contrast.

Yedutenko, Matthew / Howlett, Marcus H C / Kamermans, Maarten

Frontiers in cellular neuroscience

2021 Volume 14, Page(s) 595193

Abstract: The goal of sensory processing is to represent the environment of an animal. All sensory systems share a similar constraint: they need to encode a wide range of stimulus magnitudes within their narrow neuronal response range. The most efficient way, ... ...

Abstract	The goal of sensory processing is to represent the environment of an animal. All sensory systems share a similar constraint: they need to encode a wide range of stimulus magnitudes within their narrow neuronal response range. The most efficient way, exploited by even the simplest nervous systems, is to encode relative changes in stimulus magnitude rather than the absolute magnitudes. For instance, the retina encodes contrast, which are the variations of light intensity occurring in time and in space. From this perspective, it is easy to understand why the bright plumage of a moving bird gains a lot of attention, while an octopus remains motionless and mimics its surroundings for concealment. Stronger contrasts simply cause stronger visual signals. However, the gains in retinal performance associated with higher contrast are far more than what can be attributed to just a trivial linear increase in signal strength. Here we discuss how this improvement in performance is reflected throughout different parts of the neural circuitry, within its neural code and how high contrast activates many non-linear mechanisms to unlock several sophisticated retinal computations that are virtually impossible in low contrast conditions.
Language	English
Publishing date	2021-01-15
Publishing country	Switzerland
Document type	Journal Article
ZDB-ID	2452963-1
ISSN	1662-5102
ISSN	1662-5102
DOI	10.3389/fncel.2020.595193
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Article ; Online: A common cause for nystagmus in different congenital stationary night blindness mouse models.

Hölzel, Maj-Britt / Kamermans, Wouter / Winkelman, Beerend H J / Howlett, Marcus H C / De Zeeuw, Chris I / Kamermans, Maarten

The Journal of physiology

2023 Volume 601, Issue 23, Page(s) 5317–5340

Abstract: ... In ... ...

Abstract	In Nyx
MeSH term(s)	Mice ; Animals ; Nystagmus, Congenital ; Night Blindness/genetics ; Night Blindness/metabolism ; Myopia/genetics ; Myopia/metabolism ; Retinal Ganglion Cells/physiology ; Mutation ; Electroretinography
Language	English
Publishing date	2023-10-21
Publishing country	England
Document type	Journal Article
ZDB-ID	3115-x
ISSN	1469-7793 ; 0022-3751
ISSN (online)	1469-7793
ISSN	0022-3751
DOI	10.1113/JP284965
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Article ; Online: Silent-substitution stimuli silence the light responses of cones but not their output.

Kamar, Sizar / Howlett, Marcus H C / Kamermans, Maarten

Journal of vision

2019 Volume 19, Issue 5, Page(s) 14

Abstract: Chromatic vision starts at the retinal photoreceptors but photoreceptors are themselves color-blind, responding only to their effective quantal catch and not to the wavelength of the caught photon per se. Mitchell and Rushton (1971) termed this ... ...

Abstract	Chromatic vision starts at the retinal photoreceptors but photoreceptors are themselves color-blind, responding only to their effective quantal catch and not to the wavelength of the caught photon per se. Mitchell and Rushton (1971) termed this phenomenon the univariance concept, and it is widely used in designing silent-substitution stimuli to test the unique contributions of specific photoreceptor types to vision. In principle, this procedure controls the effective quantal catch of photoreceptors well and hence works at the phototransduction-cascade level of vision. However, both phototransduction-cascade modulation and the horizontal-cell-mediated feedback signal determine photoreceptor output. Horizontal cells receive input from, and send feedback to, more than one photoreceptor type. This should mean that silent-substitution stimuli do not silence horizontal-cell activity, and that this activity is fed back to the silenced cones. This in turn will modulate the output of silenced cones, making them not so silent after all. Here we tested this idea and found that silent-substitution stimuli can adequately silence cone-membrane potential responses. However, these cones still received a feedback signal from horizontal cells, which modulates their Ca2+ current and thus their output. These feedback-induced Ca2+-current changes are substantial, as they are of the same order of magnitude as Ca2+-current changes that occur when cones are directly stimulated with light. This illustrates that great care needs to be taken in interpreting results obtained with silent-substitution stimuli. In the discussion, we outline two basic types of interpretation pitfalls that can occur.
MeSH term(s)	Animals ; Color Vision/physiology ; Goldfish ; Models, Animal ; Photic Stimulation ; Retinal Cone Photoreceptor Cells/physiology
Language	English
Publishing date	2019-05-17
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2106064-2
ISSN	1534-7362 ; 1534-7362
ISSN (online)	1534-7362
ISSN	1534-7362
DOI	10.1167/19.5.14
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Article ; Online: An Ultrastructural and Immunohistochemical Analysis of the Outer Plexiform Layer of the Retina of the European Silver Eel (Anguilla anguilla L).

Klooster, Jan / Kamermans, Maarten

PloS one

2016 Volume 11, Issue 3, Page(s) e0152967

Abstract: Here we studied the ultrastructural organization of the outer retina of the European silver eel, a highly valued commercial fish species. The retina of the European eel has an organization very similar to most vertebrates. It contains both rod and cone ... ...

Abstract	Here we studied the ultrastructural organization of the outer retina of the European silver eel, a highly valued commercial fish species. The retina of the European eel has an organization very similar to most vertebrates. It contains both rod and cone photoreceptors. Rods are abundantly present and immunoreactive for rhodopsin. Cones are sparsely present and only show immunoreactivity for M-opsin and not for L-, S- or UV-cone opsins. As in all other vertebrate retinas, Müller cells span the width of the retina. OFF-bipolar cells express the ionotropic glutamate receptor GluR4 and ON-bipolar cells, as identified by their PKCα immunoreactivity, express the metabotropic receptor mGluR6. Both the ON- and the OFF-bipolar cell dendrites innervate the cone pedicle and rod spherule. Horizontal cells are surrounded by punctate Cx53.8 immunoreactivity indicating that the horizontal cells are strongly electrically coupled by gap-junctions. Connexin-hemichannels were found at the tips of the horizontal cell dendrites invaginating the photoreceptor synapse. Such hemichannels are implicated in the feedback pathway from horizontal cells to cones. Finally, horizontal cells are surrounded by tyrosine hydroxylase immunoreactivity, illustrating a strong dopaminergic input from interplexiform cells.
MeSH term(s)	Anguilla/anatomy & histology ; Animals ; Ependymoglial Cells/ultrastructure ; Immunohistochemistry ; Opsins/analysis ; Photoreceptor Cells/ultrastructure ; Protein Kinase C-alpha/analysis ; Receptors, AMPA/analysis ; Retina/ultrastructure ; Retinal Bipolar Cells/ultrastructure ; Retinal Horizontal Cells/ultrastructure
Chemical Substances	Opsins ; Receptors, AMPA ; glutamate receptor ionotropic, AMPA 4 ; Protein Kinase C-alpha (EC 2.7.11.13)
Language	English
Publishing date	2016-03-31
Publishing country	United States
Document type	Journal Article
ISSN	1932-6203
ISSN (online)	1932-6203
DOI	10.1371/journal.pone.0152967
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Article ; Online: Feedback-induced glutamate spillover enhances negative feedback from horizontal cells to cones.

Vroman, Rozan / Kamermans, Maarten

The Journal of physiology

2015 Volume 593, Issue 13, Page(s) 2927–2940

Abstract: Key points: In the retina, horizontal cells feed back negatively to cone photoreceptors. Glutamate released from cones can spill over to neighbouring cones. Here we show that cone glutamate release induced by negative feedback can also spill over to ... ...

Abstract	Key points: In the retina, horizontal cells feed back negatively to cone photoreceptors. Glutamate released from cones can spill over to neighbouring cones. Here we show that cone glutamate release induced by negative feedback can also spill over to neighbouring cones. This glutamate activates the glutamate transporter-associated chloride current in these neighbouring cones, which leads to a change in their membrane potential and thus modulates their output. In this way, feedback-induced glutamate spillover enhances negative feedback from horizontal cells to cones, thus forming an additional feedback pathway. This effect will be particularly prominent in cones that are strongly hyperpolarized by light. Abstract: Inhibition in the outer retina functions via an unusual mechanism. When horizontal cells hyperpolarize the activation potential of the Ca(2+) current of cones shifts to more negative potentials. The underlying mechanism consists of an ephaptic component and a Panx1/ATP-mediated component. Here we identified a third feedback component, which remains active outside the operating range of the Ca(2+) current. We show that the glutamate transporters of cones can be activated by glutamate released from their neighbours. This pathway can be triggered by negative feedback from horizontal cells to cones, thus providing an additional feedback pathway. This additional pathway is mediated by a Cl(-) current, can be blocked by either removing the gradient of K(+) or by adding the glutamate transporter blocker TBOA, or low concentrations of Zn(2+) . These features point to a glutamate transporter-associated Cl(-) current. The pathway has a delay of 4.7 ± 1.7 ms. The effectiveness of this pathway in modulating the cone output depends on the equilibrium potential of Cl(-) (ECl ) and the membrane potential of the cone. Because estimates of ECl show that it is around the dark resting membrane potential of cones, the activation of the glutamate transporter-associated Cl(-) current will be most effective in changing the membrane potential during strong hyperpolarization of cones. This means that negative feedback would particularly be enhanced by this pathway when cones are hyperpolarized. Spatially, this pathway does not reach further than the direct neighbouring cones. The consequence is that this feedback pathway transmits information between cones of different spectral type.
MeSH term(s)	Action Potentials ; Amino Acid Transport System X-AG/antagonists & inhibitors ; Amino Acid Transport System X-AG/metabolism ; Animals ; Calcium/metabolism ; Chlorides/metabolism ; Exocytosis ; Feedback, Physiological ; Glutamic Acid/metabolism ; Goldfish ; Retinal Cone Photoreceptor Cells/metabolism ; Retinal Cone Photoreceptor Cells/physiology ; Retinal Horizontal Cells/metabolism ; Retinal Horizontal Cells/physiology
Chemical Substances	Amino Acid Transport System X-AG ; Chlorides ; Glutamic Acid (3KX376GY7L) ; Calcium (SY7Q814VUP)
Language	English
Publishing date	2015-07-01
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	3115-x
ISSN	1469-7793 ; 0022-3751
ISSN (online)	1469-7793
ISSN	0022-3751
DOI	10.1113/JP270158
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Article ; Online: A novel mechanism of cone photoreceptor adaptation.

Howlett, Marcus H C / Smith, Robert G / Kamermans, Maarten

PLoS biology

2017 Volume 15, Issue 4, Page(s) e2001210

Abstract: An animal's ability to survive depends on its sensory systems being able to adapt to a wide range of environmental conditions, by maximizing the information extracted and reducing the noise transmitted. The visual system does this by adapting to ... ...

Abstract	An animal's ability to survive depends on its sensory systems being able to adapt to a wide range of environmental conditions, by maximizing the information extracted and reducing the noise transmitted. The visual system does this by adapting to luminance and contrast. While luminance adaptation can begin at the retinal photoreceptors, contrast adaptation has been shown to start at later stages in the retina. Photoreceptors adapt to changes in luminance over multiple time scales ranging from tens of milliseconds to minutes, with the adaptive changes arising from processes within the phototransduction cascade. Here we show a new form of adaptation in cones that is independent of the phototransduction process. Rather, it is mediated by voltage-gated ion channels in the cone membrane and acts by changing the frequency response of cones such that their responses speed up as the membrane potential modulation depth increases and slow down as the membrane potential modulation depth decreases. This mechanism is effectively activated by high-contrast stimuli dominated by low frequencies such as natural stimuli. However, the more generally used Gaussian white noise stimuli were not effective since they did not modulate the cone membrane potential to the same extent. This new adaptive process had a time constant of less than a second. A critical component of the underlying mechanism is the hyperpolarization-activated current, Ih, as pharmacologically blocking it prevented the long- and mid- wavelength sensitive cone photoreceptors (L- and M-cones) from adapting. Consistent with this, short- wavelength sensitive cone photoreceptors (S-cones) did not show the adaptive response, and we found they also lacked a prominent Ih. The adaptive filtering mechanism identified here improves the information flow by removing higher-frequency noise during lower signal-to-noise ratio conditions, as occurs when contrast levels are low. Although this new adaptive mechanism can be driven by contrast, it is not a contrast adaptation mechanism in its strictest sense, as will be argued in the Discussion.
MeSH term(s)	Action Potentials ; Adaptation, Ocular ; Animals ; Goldfish ; Kinetics ; Retinal Cone Photoreceptor Cells/physiology ; Retinal Cone Photoreceptor Cells/radiation effects
Language	English
Publishing date	2017-04-12
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
ZDB-ID	2126776-5
ISSN	1545-7885 ; 1544-9173
ISSN (online)	1545-7885
ISSN	1544-9173
DOI	10.1371/journal.pbio.2001210
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