scholarly journals Melanopic stimulation does not alter psychophysical threshold sensitivity for luminance flicker

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Joris Vincent ◽  
Edda B. Haggerty ◽  
David H. Brainard ◽  
Geoffrey K. Aguirre
Keyword(s):  
Circadian Rhythm ◽  
Visual Perception ◽  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Threshold Sensitivity ◽  
Retinal Ganglion ◽  
Pupil Response ◽  
Visual Functions ◽  
Psychophysical Threshold ◽  
Rod And Cone Photoreceptors

AbstractIn addition to the rod and cone photoreceptors the retina contains intrinsically photosensitive retinal ganglion cells (ipRGCs). These cells express the photopigment melanopsin and are known to be involved in reflexive visual functions such as pupil response and photo-entrainment of the circadian rhythm. It is possible that the ipRGCs contribute to conscious visual perception, either by providing an independent signal to the geniculo-striate pathway, or by interacting with and thus modifying signals arising from “classical” retinal ganglion cells that combine and contrast cone input. Here, we tested for the existence of an interaction by asking if a 350% change in melanopsin stimulation alters psychophysical sensitivity for the detection of luminance flicker. In Experiment 1, we tested for a change in the threshold for detecting luminance flicker in three participants after they adapted to backgrounds with different degrees of tonic melanopsin stimulation. In Experiments 2 and 3, this test was repeated, but now for luminance flicker presented on a transient pedestal of melanopsin stimulation. Across the three experiments, no effect of melanopsin stimulation upon threshold flicker sensitivity was found. Our results suggest that even large changes in melanopsin stimulation do not affect near-threshold, cone-mediated visual perception.

scholarly journals Melanopic stimulation does not affect psychophysical threshold sensitivity for luminance flicker

2021 ◽  
Author(s):  
Joris Vincent ◽  
Edda B Haggerty ◽  
David H. Brainard ◽  
Geoffrey Karl Aguirre
Keyword(s):  
Circadian Rhythm ◽  
Visual Perception ◽  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Threshold Sensitivity ◽  
Retinal Ganglion ◽  
Cone Photoreceptors ◽  
Pupil Response ◽  
Visual Functions ◽  
Psychophysical Threshold

In addition to the cone photoreceptors the retina contains intrinsically photosensitive retinal ganglion cells (ipRGCs). These cells express the photopigment melanopsin and are known to be involved in reflexive visual functions such as pupil response and photo-entrainment of the circadian rhythm. It is possible that the ipRGCs contribute to conscious visual perception, either by providing an independent signal to the geniculo-striate pathway, or by interacting with and thus modifying signals arising from "classical" retinal ganglion cells that combine and contrast cone input. Here, we tested for the existence of an interaction by asking if a 350% change in melanopsin stimulation alters psychophysical sensitivity for the detection of luminance flicker. In Experiment 1, we tested for a change in the threshold for detecting luminance flicker in three participants after they adapted to backgrounds with different degrees of tonic melanopsin stimulation. In Experiments 2 and 3, this test was repeated, but now for luminance flicker presented on a transient pedestal of melanopsin stimulation. Across the three experiments, no effect of melanopsin stimulation upon threshold flicker sensitivity was found. Our results suggest that even large changes in melanopsin stimulation do not affect near-threshold, cone-mediated visual perception.

scholarly journals Binocular Summation in Postillumination Pupil Response Driven by Melanopsin-Containing Retinal Ganglion Cells

2018 ◽  
Vol 59 (12) ◽  
pp. 4968 ◽  
Author(s):  
Marija Zivcevska ◽  
Alan Blakeman ◽  
Shaobo Lei ◽  
Herbert C. Goltz ◽  
Agnes M. F. Wong
Keyword(s):  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Binocular Summation ◽  
Retinal Ganglion ◽  
Pupil Response

scholarly journals Photosensitive Melanopsin-Containing Retinal Ganglion Cells in Health and Disease: Implications for Circadian Rhythms

2019 ◽  
Vol 20 (13) ◽  
pp. 3164 ◽  
Author(s):  
Pedro Lax ◽  
Isabel Ortuño-Lizarán ◽  
Victoria Maneu ◽  
Manuel Vidal-Sanz ◽  
Nicolás Cuenca
Keyword(s):  
Circadian Rhythm ◽  
Circadian Rhythms ◽  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Well Being ◽  
Average Density ◽  
Retinal Ganglion ◽  
Healthy Humans ◽  
Cell Alterations ◽  
Circadian Rhythm Disorders

Melanopsin-containing retinal ganglion cells (mRGCs) represent a third class of retinal photoreceptors involved in regulating the pupillary light reflex and circadian photoentrainment, among other things. The functional integrity of the circadian system and melanopsin cells is an essential component of well-being and health, being both impaired in aging and disease. Here we review evidence of melanopsin-expressing cell alterations in aging and neurodegenerative diseases and their correlation with the development of circadian rhythm disorders. In healthy humans, the average density of melanopsin-positive cells falls after age 70, accompanied by age-dependent atrophy of dendritic arborization. In addition to aging, inner and outer retinal diseases also involve progressive deterioration and loss of mRGCs that positively correlates with progressive alterations in circadian rhythms. Among others, mRGC number and plexus complexity are impaired in Parkinson’s disease patients; changes that may explain sleep and circadian rhythm disorders in this pathology. The key role of mRGCs in circadian photoentrainment and their loss in age and disease endorse the importance of eye care, even if vision is lost, to preserve melanopsin ganglion cells and their essential functions in the maintenance of an adequate quality of life.

scholarly journals Selective amplification of ipRGC signals accounts for interictal photophobia in migraine

2020 ◽  
Author(s):  
Harrison McAdams ◽  
Eric A Kaiser ◽  
Aleksandra Igdalova ◽  
Edda B Haggerty ◽  
Brett Cucchiara ◽  
...  
Keyword(s):  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Group Differences ◽  
Retinal Ganglion ◽  
Spectral Change ◽  
Visual Discomfort ◽  
Selective Amplification ◽  
Pupil Response ◽  
Migraine Group

AbstractSecond only to headache, photophobia is the most debilitating symptom reported by people with migraine. While the melanopsin-containing, intrinsically photosensitive retinal ganglion cells (ipRGCs) are thought to play a role, how cone and melanopsin signals are integrated in this pathway to produce visual discomfort is poorly understood.We studied 60 people: 20 without headache and 20 each with interictal photophobia from migraine with or without aura. Participants viewed pulses of spectral change that selectively targeted melanopsin, the cones, or both, and rated the degree of visual discomfort produced by these stimuli while we also recorded pupil responses.We examined the data within a model that describes how cone and melanopsin signals are weighted and combined at the level of the retina, and how this combined signal is transformed into a rating of discomfort or pupil response. Our results indicate that people with migraine do not differ from headache-free controls in the manner in which melanopsin and cone signals are combined. Instead, people with migraine demonstrate an amplification of integrated ipRGC signals for discomfort. This effect of migraine is selective for ratings of visual discomfort, in that an amplification of pupil responses was not seen in the migraine group, nor were group differences found in surveys of other behaviors putatively linked to ipRGC function (chronotype, seasonal sensitivity, presence of a photic sneeze reflex).By revealing a dissociation in the amplification of discomfort versus pupil response, our findings suggest a post-retinal alteration in processing of ipRGC signals for photophobia in migraine.SignificanceThe melanopsin-containing, intrinsically photosensitive retinal ganglion cells (ipRGCs) may contribute to photophobia in migraine. We measured visual discomfort and pupil responses to cone and melanopsin stimulation—the photoreceptor inputs to the ipRGCs—in people with and without migraine. We find that people with migraine do not differ from those without headaches in how cone and melanopsin signals are weighted and combined to produce visual discomfort. Instead, migraine is associated with an amplification of ipRGC signals for discomfort. This effect of migraine upon ipRGC signals is limited to photophobia, as we did not find an enhancement of pupil responses or a change in other behaviors linked to ipRGC function. Our findings suggest a post-retinal amplification of ipRGC signals for photophobia in migraine.

scholarly journals Selective amplification of ipRGC signals accounts for interictal photophobia in migraine

2020 ◽  
Vol 117 (29) ◽  
pp. 17320-17329 ◽  
Author(s):  
Harrison McAdams ◽  
Eric A. Kaiser ◽  
Aleksandra Igdalova ◽  
Edda B. Haggerty ◽  
Brett Cucchiara ◽  
...  
Keyword(s):  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Group Differences ◽  
Retinal Ganglion ◽  
Spectral Change ◽  
Visual Aura ◽  
Visual Discomfort ◽  
Selective Amplification ◽  
Pupil Response ◽  
Migraine Group

Second only to headache, photophobia is the most debilitating symptom reported by people with migraine. While the melanopsin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs) are thought to play a role, how cone and melanopsin signals are integrated in this pathway to produce visual discomfort is poorly understood. We studied 60 people: 20 without headache and 20 each with interictal photophobia from migraine with or without visual aura. Participants viewed pulses of spectral change that selectively targeted melanopsin, the cones, or both and rated the degree of visual discomfort produced by these stimuli while we recorded pupil responses. We examined the data within a model that describes how cone and melanopsin signals are weighted and combined at the level of the retina and how this combined signal is transformed into a rating of discomfort or pupil response. Our results indicate that people with migraine do not differ from headache-free controls in the manner in which melanopsin and cone signals are combined. Instead, people with migraine demonstrate an enhanced response to integrated ipRGC signals for discomfort. This effect of migraine is selective for ratings of visual discomfort, in that an enhancement of pupil responses was not seen in the migraine group, nor were group differences found in surveys of other behaviors putatively linked to ipRGC function (chronotype, seasonal sensitivity, presence of a photic sneeze reflex). By revealing a dissociation in the amplification of discomfort vs. pupil response, our findings suggest a postretinal alteration in processing of ipRGC signals for photophobia in migraine.

scholarly journals Inhibitory masking controls the threshold sensitivity of retinal ganglion cells

2016 ◽  
Vol 594 (22) ◽  
pp. 6679-6699 ◽  
Author(s):  
Feng Pan ◽  
Abduqodir Toychiev ◽  
Yi Zhang ◽  
Tamas Atlasz ◽  
Hariharasubramanian Ramakrishnan ◽  
...  
Keyword(s):  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Threshold Sensitivity ◽  
Retinal Ganglion
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