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Hartstein LE, LeBourgeois MK, Durniak MT, Najjar RP. Differences in the pupillary responses to evening light between children and adolescents. J Physiol Anthropol 2024; 43:16. [PMID: 38961509 PMCID: PMC11221120 DOI: 10.1186/s40101-024-00363-6] [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: 02/09/2024] [Accepted: 06/04/2024] [Indexed: 07/05/2024] Open
Abstract
BACKGROUND In the mammalian retina, intrinsically-photosensitive retinal ganglion cells (ipRGC) detect light and integrate signals from rods and cones to drive multiple non-visual functions including circadian entrainment and the pupillary light response (PLR). Non-visual photoreception and consequently non-visual sensitivity to light may change across child development. The PLR represents a quick and reliable method for examining non-visual responses to light in children. The purpose of this study was to assess differences in the PLRs to blue and red stimuli, measured one hour prior to bedtime, between children and adolescents. METHODS Forty healthy participants (8-9 years, n = 21; 15-16 years, n = 19) completed a PLR assessment 1 h before their habitual bedtime. After a 1 h dim-light adaptation period (< 1 lx), baseline pupil diameter was measured in darkness for 30 s, followed by a 10 s exposure to 3.0 × 1013 photons/cm2/s of either red (627 nm) or blue (459 nm) light, and a 40 s recovery in darkness to assess pupillary re-dilation. Subsequently, participants underwent 7 min of dim-light re-adaptation followed by an exposure to the other light condition. Lights were counterbalanced across participants. RESULTS Across both age groups, maximum pupil constriction was significantly greater (p < 0.001, ηp2 = 0.48) and more sustained (p < 0.001, ηp2 = 0.41) during exposure to blue compared to red light. For adolescents, the post-illumination pupillary response (PIPR), a hallmark of melanopsin function, was larger after blue compared with red light (p = 0.02, d = 0.60). This difference was not observed in children. Across light exposures, children had larger phasic (p < 0.01, ηp2 = 0.20) and maximal (p < 0.01, ηp2 = 0.22) pupil constrictions compared to adolescents. CONCLUSIONS Blue light elicited a greater and more sustained pupillary response than red light in children and adolescents. However, the overall amplitude of the rod/cone-driven phasic response was greater in children than in adolescents. Our findings using the PLR highlight a higher sensitivity to evening light in children compared to adolescents, and continued maturation of the human non-visual photoreception/system throughout development.
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Affiliation(s)
- Lauren E Hartstein
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA.
| | - Monique K LeBourgeois
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | | | - Raymond P Najjar
- Center for Innovation & Precision Eye Health, Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- ASPIRE Research Program, Singapore Eye Research Institute, Singapore, Singapore
- Duke-NUS School of Medicine, Singapore, Singapore
- Department of Biomedical Engineering, College of Design and Engineering, National University of Singapore, Singapore, Singapore
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Hartstein LE, LeBourgeois MK, Durniak MT, Najjar RP. Differences in the Pupillary Responses to Evening Light between Children and Adolescents. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.09.552691. [PMID: 37645820 PMCID: PMC10461909 DOI: 10.1101/2023.08.09.552691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Purpose To assess differences in the pupillary light responses (PLRs) to blue and red evening lights between children and adolescents. Methods Forty healthy participants (8-9 years, n=21; 15-16 years, n=19) completed a PLR assessment 1 h before their habitual bedtime. After a 1 h dim-light adaptation period (<1 lux), baseline pupil diameter was measured in darkness for 30 s, followed by a 10 s exposure to 3.0×1013 photons/cm2/s of either red (627 nm) or blue (459 nm) light, and a 40 s recovery in darkness to assess pupillary re-dilation. Subsequently, participants underwent 7 min of dim-light re-adaptation followed by an exposure to the other light condition. Lights were counterbalanced across participants. Results Across both age groups, maximum pupil constriction was significantly greater (p< 0.001, ηp2=0.48) and more sustained (p< 0.001, ηp2=0.41) during exposure to blue compared to red light. For adolescents, the post-illumination pupillary response (PIPR), a hallmark of melanopsin function, was larger after blue compared with red light (p= 0.02, d=0.60). This difference was not observed in children. Across light exposures, children had larger phasic (p< 0.01, ηp2=0.20) and maximal (p< 0.01, ηp2=0.22) pupil constrictions compared to adolescents. Conclusions Blue light elicited a greater and more sustained pupillary response than red light across participants. However, the overall amplitude of the rod/cone-driven phasic response was greater in children than in adolescents. Our findings using the PLR highlight a higher sensitivity to evening light in children compared to adolescents, and continued maturation of the human non-visual photoreception/system throughout development.
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Affiliation(s)
- Lauren E. Hartstein
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | | | | | - Raymond P. Najjar
- Center for Innovation & Precision Eye Health, Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- ASPIRE Research Program, Singapore Eye Research Institute, Singapore
- Duke-NUS School of Medicine, Singapore
- Department of Biomedical Engineering, College of Design and Engineering, National University of Singapore, Singapore
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Quan Y, Duan H, Zhan Z, Shen Y, Lin R, Liu T, Zhang T, Wu J, Huang J, Zhai G, Song X, Zhou Y, Sun X. Binocular head-mounted chromatic pupillometry can detect structural and functional loss in glaucoma. Front Neurosci 2023; 17:1187619. [PMID: 37456990 PMCID: PMC10346847 DOI: 10.3389/fnins.2023.1187619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 06/07/2023] [Indexed: 07/18/2023] Open
Abstract
Aim The aim of this study is to evaluate the utility of binocular chromatic pupillometry in detecting impaired pupillary light response (PLR) in patients with primary open-angle glaucoma (POAG) and to assess the feasibility of using binocular chromatic pupillometer in opportunistic POAG diagnosis in community-based or telemedicine-based services. Methods In this prospective, cross-sectional study, 74 patients with POAG and 23 healthy controls were enrolled. All participants underwent comprehensive ophthalmologic examinations including optical coherence tomography (OCT) and standard automated perimetry (SAP). The PLR tests included sequential tests of full-field chromatic stimuli weighted by rods, intrinsically photosensitive retinal ganglion cells (ipRGCs), and cones (Experiment 1), as well as alternating chromatic light flash-induced relative afferent pupillary defect (RAPD) test (Experiment 2). In Experiment 1, the constricting amplitude, velocity, and time to maximum constriction/dilation were calculated in three cell type-weighted responses, and the post-illumination response of ipRGC-weighted response was evaluated. In Experiment 2, infrared pupillary asymmetry (IPA) amplitude and anisocoria duration induced by intermittent blue or red light flashes were calculated. Results In Experiment 1, the PLR of POAG patients was significantly reduced in all conditions, reflecting the defect in photoreception through rods, cones, and ipRGCs. The variable with the highest area under the receiver operating characteristic curve (AUC) was time to max dilation under ipRGC-weighted stimulus, followed by the constriction amplitude under cone-weighted stimulus and the constriction amplitude response to ipRGC-weighted stimuli. The impaired PLR features were associated with greater visual field loss, thinner retinal nerve fiber layer (RNFL) thickness, and cupping of the optic disk. In Experiment 2, IPA and anisocoria duration induced by intermittent blue or red light flashes were significantly greater in participants with POAG than in controls. IPA and anisocoria duration had good diagnostic value, correlating with the inter-eye asymmetry of visual field loss. Conclusion We demonstrate that binocular chromatic pupillometry could potentially serve as an objective clinical tool for opportunistic glaucoma diagnosis in community-based or telemedicine-based services. Binocular chromatic pupillometry allows an accurate, objective, and rapid assessment of retinal structural impairment and functional loss in glaucomatous eyes of different severity levels.
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Affiliation(s)
- Yadan Quan
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
- NHC and Chinese Academy of Medical Sciences Key Laboratory of Myopia, Fudan University, Shanghai, China
| | - Huiyu Duan
- Institute of Image Communication and Network Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Zongyi Zhan
- Department of Retinal Disease, Shenzhen Eye Institute, Shenzhen Eye Hospital, Shenzhen Eye Hospital Affiliated to Jinan University, Shenzhen, China
| | - Yuening Shen
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
| | - Rui Lin
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
- NHC and Chinese Academy of Medical Sciences Key Laboratory of Myopia, Fudan University, Shanghai, China
| | - Tingting Liu
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
- NHC and Chinese Academy of Medical Sciences Key Laboratory of Myopia, Fudan University, Shanghai, China
| | - Ting Zhang
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
- NHC and Chinese Academy of Medical Sciences Key Laboratory of Myopia, Fudan University, Shanghai, China
| | - Jihong Wu
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
- NHC and Chinese Academy of Medical Sciences Key Laboratory of Myopia, Fudan University, Shanghai, China
| | - Jing Huang
- Institute of Image Communication and Network Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Guangtao Zhai
- Institute of Image Communication and Network Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Xuefei Song
- Department of Ophthalmology, Ninth People's Hospital of Shanghai, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Yixiong Zhou
- Department of Ophthalmology, Ninth People's Hospital of Shanghai, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Xinghuai Sun
- Department of Ophthalmology and Visual Science, Shanghai Medical College, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
- NHC and Chinese Academy of Medical Sciences Key Laboratory of Myopia, Fudan University, Shanghai, China
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, China
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Portengen BL, Porro GL, Bergsma D, Veldman EJ, Imhof SM, Naber M. Effects of Stimulus Luminance, Stimulus Color and Intra-Stimulus Color Contrast on Visual Field Mapping in Neurologically Impaired Adults Using Flicker Pupil Perimetry. Eye Brain 2023; 15:77-89. [PMID: 37287993 PMCID: PMC10243349 DOI: 10.2147/eb.s409905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 05/07/2023] [Indexed: 06/09/2023] Open
Abstract
Purpose We improve pupillary responses and diagnostic performance of flicker pupil perimetry through alterations in global and local color contrast and luminance contrast in adult patients suffering from visual field defects due to cerebral visual impairment (CVI). Methods Two experiments were conducted on patients with CVI (Experiment 1: 19 subjects, age M and SD 57.9 ± 14.0; Experiment 2: 16 subjects, age M and SD 57.3 ± 14.7) suffering from absolute homonymous visual field (VF) defects. We altered global color contrast (stimuli consisted of white, yellow, cyan and yellow-equiluminant-to-cyan colored wedges) in Experiment 1, and we manipulated luminance and local color contrast with bright and dark yellow and multicolor wedges in a 2-by-2 design in Experiment 2. Stimuli consecutively flickered across 44 stimulus locations within the inner 60 degrees of the VF and were offset to a contrasting (opponency colored) dark background. Pupil perimetry results were compared to standard automated perimetry (SAP) to assess diagnostic accuracy. Results A bright stimulus with global color contrast using yellow (p= 0.009) or white (p= 0.006) evoked strongest pupillary responses as opposed to stimuli containing local color contrast and lower brightness. Diagnostic accuracy, however, was similar across global color contrast conditions in Experiment 1 (p= 0.27) and decreased when local color contrast and less luminance contrast was introduced in Experiment 2 (p= 0.02). The bright yellow condition resulted in highest performance (AUC M = 0.85 ± 0.10, Mdn = 0.85). Conclusion Pupillary responses and pupil perimetry's diagnostic accuracy both benefit from high luminance contrast and global but not local color contrast.
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Affiliation(s)
- Brendan L Portengen
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, the Netherlands
- Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, the Netherlands
| | - Giorgio L Porro
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, the Netherlands
| | | | | | - Saskia M Imhof
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Marnix Naber
- Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, the Netherlands
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Portengen BL, Porro GL, Imhof SM, Naber M. The Trade-Off Between Luminance and Color Contrast Assessed With Pupil Responses. Transl Vis Sci Technol 2023; 12:15. [PMID: 36622687 PMCID: PMC9838585 DOI: 10.1167/tvst.12.1.15] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Purpose A scene consisting of a white stimulus on a black background incorporates strong luminance contrast. When both stimulus and background receive different colors, luminance contrast decreases but color contrast increases. Here, we sought to characterize the pattern of stimulus salience across varying trade-offs of color and luminance contrasts by using the pupil light response. Methods Three experiments were conducted with 17, 16, and 17 healthy adults. For all experiments, a flickering stimulus (2 Hz; alternating color to black) was presented superimposed on a background with a complementary color to the stimulus (i.e., opponency colors in human color perception: blue and yellow for Experiment 1, red and green for Experiment 2, and equiluminant red and green for Experiment 3). Background luminance varied between 0% and 45% to trade off luminance and color contrast with the stimulus. By comparing the locus of the optimal trade-off between color and luminance across different color axes, we explored the generality of the trade-off. Results The strongest pupil responses were found when a substantial amount of color contrast was present (at the expense of luminance contrast). Pupil response amplitudes increased by 15% to 30% after the addition of color contrast. An optimal pupillary responsiveness was reached at a background luminance setting of 20% to 35% color contrast across several color axes. Conclusions These findings suggest that a substantial component of pupil light responses incorporates color processing. More sensitive pupil responses and more salient stimulus designs can be achieved by adding subtle levels of color contrast between stimulus and background. Translational Relevance More robust pupil responses will enhance tests of the visual field with pupil perimetry.
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Affiliation(s)
- Brendan L. Portengen
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, The Netherlands,Department of Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands
| | - Giorgio L. Porro
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Saskia M. Imhof
- Department of Ophthalmology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Marnix Naber
- Department of Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands
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Machine learning for comprehensive prediction of high risk for Alzheimer's disease based on chromatic pupilloperimetry. Sci Rep 2022; 12:9945. [PMID: 35705601 PMCID: PMC9200977 DOI: 10.1038/s41598-022-13999-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 05/13/2022] [Indexed: 11/30/2022] Open
Abstract
Currently there are no reliable biomarkers for early detection of Alzheimer's disease (AD) at the preclinical stage. This study assessed the pupil light reflex (PLR) for focal red and blue light stimuli in central and peripheral retina in 125 cognitively normal middle age subjects (45–71 years old) at high risk for AD due to a family history of the disease (FH+), and 61 age-similar subjects with no family history of AD (FH−) using Chromatic Pupilloperimetry coupled with Machine Learning (ML). All subjects had normal ophthalmic assessment, and normal retinal and optic nerve thickness by optical coherence tomography. No significant differences were observed between groups in cognitive function and volumetric brain MRI. Chromatic pupilloperimetry-based ML models were highly discriminative in differentiating subjects with and without AD family history, using transient PLR for focal red (primarily cone-mediated), and dim blue (primarily rod-mediated) light stimuli. Features associated with transient pupil response latency (PRL) achieved Area Under the Curve Receiver Operating Characteristic (AUC-ROC) of 0.90 ± 0.051 (left-eye) and 0.87 ± 0.048 (right-eye). Parameters associated with the contraction arm of the rod and cone-mediated PLR were more discriminative compared to parameters associated with the relaxation arm and melanopsin-mediated PLR. Significantly shorter PRL for dim blue light was measured in the FH+ group in two test targets in the temporal visual field in right eye that had highest relative weight in the ML algorithm (mean ± standard error, SE 0.449 s ± 0.007 s vs. 0.478 s ± 0.010 s, p = 0.038). Taken together our study suggests that subtle focal changes in pupil contraction latency may be detected in subjects at high risk to develop AD, decades before the onset of AD clinical symptoms. The dendrites of melanopsin containing retinal ganglion cells may be affected very early at the preclinical stages of AD.
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Chakraborty R, Collins MJ, Kricancic H, Moderiano D, Davis B, Alonso-Caneiro D, Yi F, Baskaran K. The intrinsically photosensitive retinal ganglion cell (ipRGC) mediated pupil response in young adult humans with refractive errors. JOURNAL OF OPTOMETRY 2022; 15:112-121. [PMID: 33402286 PMCID: PMC9068560 DOI: 10.1016/j.optom.2020.12.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/21/2020] [Accepted: 12/01/2020] [Indexed: 05/04/2023]
Abstract
PURPOSE The intrinsically photosensitive retinal ganglion cells (ipRGCs) signal environmental light, with axons projected to the midbrain that control pupil size and circadian rhythms. Post-illumination pupil response (PIPR), a sustained pupil constriction after short-wavelength light stimulation, is an indirect measure of ipRGC activity. Here, we measured the PIPR in young adults with various refractive errors using a custom-made optical system. METHODS PIPR was measured on myopic (-3.50 ± 1.82 D, n = 20) and non-myopic (+0.28 ± 0.23 D, n = 19) participants (mean age, 23.36 ± 3.06 years). The right eye was dilated and presented with long-wavelength (red, 625 nm, 3.68 × 1014 photons/cm2/s) and short-wavelength (blue, 470 nm, 3.24 × 1014 photons/cm2/s) 1 s and 5 s pulses of light, and the consensual response was measured in the left eye for 60 s following light offset. The 6 s and 30 s PIPR and early and late area under the curve (AUC) for 1 and 5 s stimuli were calculated. RESULTS For most subjects, the 6 s and 30 s PIPR were significantly lower (p < 0.001), and the early and late AUC were significantly larger for 1 s blue light compared to red light (p < 0.001), suggesting a strong ipRGC response. The 5 s blue stimulation induced a slightly stronger melanopsin response, compared to 1 s stimulation with the same wavelength. However, none of the PIPR metrics were different between myopes and non-myopes for either stimulus duration (p > 0.05). CONCLUSIONS We confirm previous research that there is no effect of refractive error on the PIPR.
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Affiliation(s)
- Ranjay Chakraborty
- College of Nursing and Health Sciences, Optometry and Vision Science, Sturt North, Flinders University, Sturt Rd, Bedford Park, SA 5042, Australia; Caring Futures Institute, Flinders University, Sturt Rd, Bedford Park, SA 5042, Australia.
| | - Michael J Collins
- Contact Lens and Visual Optics Laboratory, School of Optometry and Vision Science, Queensland University of Technology, Victoria Park Road, Kelvin Grove 4059, Brisbane, QLD, Australia
| | - Henry Kricancic
- Contact Lens and Visual Optics Laboratory, School of Optometry and Vision Science, Queensland University of Technology, Victoria Park Road, Kelvin Grove 4059, Brisbane, QLD, Australia
| | - Daniel Moderiano
- College of Nursing and Health Sciences, Optometry and Vision Science, Sturt North, Flinders University, Sturt Rd, Bedford Park, SA 5042, Australia
| | - Brett Davis
- Contact Lens and Visual Optics Laboratory, School of Optometry and Vision Science, Queensland University of Technology, Victoria Park Road, Kelvin Grove 4059, Brisbane, QLD, Australia
| | - David Alonso-Caneiro
- Contact Lens and Visual Optics Laboratory, School of Optometry and Vision Science, Queensland University of Technology, Victoria Park Road, Kelvin Grove 4059, Brisbane, QLD, Australia
| | - Fan Yi
- Contact Lens and Visual Optics Laboratory, School of Optometry and Vision Science, Queensland University of Technology, Victoria Park Road, Kelvin Grove 4059, Brisbane, QLD, Australia
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Zandi B, Lode M, Herzog A, Sakas G, Khanh TQ. PupilEXT: Flexible Open-Source Platform for High-Resolution Pupillometry in Vision Research. Front Neurosci 2021; 15:676220. [PMID: 34220432 PMCID: PMC8249868 DOI: 10.3389/fnins.2021.676220] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 04/28/2021] [Indexed: 12/12/2022] Open
Abstract
The human pupil behavior has gained increased attention due to the discovery of the intrinsically photosensitive retinal ganglion cells and the afferent pupil control path's role as a biomarker for cognitive processes. Diameter changes in the range of 10-2 mm are of interest, requiring reliable and characterized measurement equipment to accurately detect neurocognitive effects on the pupil. Mostly commercial solutions are used as measurement devices in pupillometry which is associated with high investments. Moreover, commercial systems rely on closed software, restricting conclusions about the used pupil-tracking algorithms. Here, we developed an open-source pupillometry platform consisting of hardware and software competitive with high-end commercial stereo eye-tracking systems. Our goal was to make a professional remote pupil measurement pipeline for laboratory conditions accessible for everyone. This work's core outcome is an integrated cross-platform (macOS, Windows and Linux) pupillometry software called PupilEXT, featuring a user-friendly graphical interface covering the relevant requirements of professional pupil response research. We offer a selection of six state-of-the-art open-source pupil detection algorithms (Starburst, Swirski, ExCuSe, ElSe, PuRe and PuReST) to perform the pupil measurement. A developed 120-fps pupillometry demo system was able to achieve a calibration accuracy of 0.003 mm and an averaged temporal pupil measurement detection accuracy of 0.0059 mm in stereo mode. The PupilEXT software has extended features in pupil detection, measurement validation, image acquisition, data acquisition, offline pupil measurement, camera calibration, stereo vision, data visualization and system independence, all combined in a single open-source interface, available at https://github.com/openPupil/Open-PupilEXT.
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Affiliation(s)
- Babak Zandi
- Laboratory of Lighting Technology, Department of Electrical Engineering and Information Technology, Technical University of Darmstadt, Darmstadt, Germany
| | - Moritz Lode
- Laboratory of Lighting Technology, Department of Electrical Engineering and Information Technology, Technical University of Darmstadt, Darmstadt, Germany
| | - Alexander Herzog
- Laboratory of Lighting Technology, Department of Electrical Engineering and Information Technology, Technical University of Darmstadt, Darmstadt, Germany
| | - Georgios Sakas
- Interactive Graphic Systems, Department of Computer Science, Technical University of Darmstadt, Darmstadt, Germany
| | - Tran Quoc Khanh
- Laboratory of Lighting Technology, Department of Electrical Engineering and Information Technology, Technical University of Darmstadt, Darmstadt, Germany
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Zandi B, Khanh TQ. Deep learning-based pupil model predicts time and spectral dependent light responses. Sci Rep 2021; 11:841. [PMID: 33436693 PMCID: PMC7803766 DOI: 10.1038/s41598-020-79908-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 12/11/2020] [Indexed: 01/29/2023] Open
Abstract
Although research has made significant findings in the neurophysiological process behind the pupillary light reflex, the temporal prediction of the pupil diameter triggered by polychromatic or chromatic stimulus spectra is still not possible. State of the art pupil models rested in estimating a static diameter at the equilibrium-state for spectra along the Planckian locus. Neither the temporal receptor-weighting nor the spectral-dependent adaptation behaviour of the afferent pupil control path is mapped in such functions. Here we propose a deep learning-driven concept of a pupil model, which reconstructs the pupil's time course either from photometric and colourimetric or receptor-based stimulus quantities. By merging feed-forward neural networks with a biomechanical differential equation, we predict the temporal pupil light response with a mean absolute error below 0.1 mm from polychromatic (2007 [Formula: see text] 1 K, 4983 [Formula: see text] 3 K, 10,138 [Formula: see text] 22 K) and chromatic spectra (450 nm, 530 nm, 610 nm, 660 nm) at 100.01 ± 0.25 cd/m2. This non-parametric and self-learning concept could open the door to a generalized description of the pupil behaviour.
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Affiliation(s)
- Babak Zandi
- Department of Electrical Engineering and Information Technology, Laboratory of Lighting Technology, Technical University of Darmstadt, 64289, Darmstadt, Germany.
| | - Tran Quoc Khanh
- Department of Electrical Engineering and Information Technology, Laboratory of Lighting Technology, Technical University of Darmstadt, 64289, Darmstadt, Germany
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Zandi B, Klabes J, Khanh TQ. Prediction accuracy of L- and M-cone based human pupil light models. Sci Rep 2020; 10:10988. [PMID: 32620793 PMCID: PMC7335057 DOI: 10.1038/s41598-020-67593-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 06/10/2020] [Indexed: 12/19/2022] Open
Abstract
Multi-channel LED luminaires offer a powerful tool to vary retinal receptor signals while keeping visual parameters such as color or brightness perception constant. This technology could provide new fields of application in indoor lighting since the spectrum can be enhanced individually to the users' favor or task. One possible application would be to optimize a light spectrum by using the pupil diameter as a parameter to increase the visual acuity. A spectral- and time-dependent pupil model is the key requirement for this aim. We benchmarked in our work selected L- and M-cone based pupil models to find the estimation error in predicting the pupil diameter for chromatic and polychromatic spectra at 100 cd/m2. We report an increased estimation error up to 1.21 mm for 450 nm at 60-300 s exposure time. At short exposure times, the pupil diameter was approximately independent of the used spectrum, allowing to use the luminance for a pupil model. Polychromatic spectra along the Planckian locus showed at 60-300 s exposure time, a prediction error within a tolerance range of ± 0.5 mm. The time dependency seems to be more essential than the spectral dependency when using polychromatic spectra.
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Affiliation(s)
- Babak Zandi
- Department of Electrical Engineering and Information Technology, Laboratory of Lighting Technology, Technical University of Darmstadt, 64289, Darmstadt, Germany.
| | - Julian Klabes
- Department of Electrical Engineering and Information Technology, Laboratory of Lighting Technology, Technical University of Darmstadt, 64289, Darmstadt, Germany
| | - Tran Quoc Khanh
- Department of Electrical Engineering and Information Technology, Laboratory of Lighting Technology, Technical University of Darmstadt, 64289, Darmstadt, Germany
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Sondereker KB, Stabio ME, Renna JM. Crosstalk: The diversity of melanopsin ganglion cell types has begun to challenge the canonical divide between image-forming and non-image-forming vision. J Comp Neurol 2020; 528:2044-2067. [PMID: 32003463 DOI: 10.1002/cne.24873] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 01/22/2020] [Accepted: 01/22/2020] [Indexed: 12/15/2022]
Abstract
Melanopsin ganglion cells have defied convention since their discovery almost 20 years ago. In the years following, many types of these intrinsically photosensitive retinal ganglion cells (ipRGCs) have emerged. In the mouse retina, there are currently six known types (M1-M6) of melanopsin ganglion cells, each with unique morphology, mosaics, connections, physiology, projections, and functions. While melanopsin-expressing cells are usually associated with behaviors like circadian photoentrainment and the pupillary light reflex, the characterization of multiple types has demonstrated a reach that may extend far beyond non-image-forming vision. In fact, studies have shown that individual types of melanopsin ganglion cells have the potential to impact image-forming functions like contrast sensitivity and color opponency. Thus, the goal of this review is to summarize the morphological and functional aspects of the six known types of melanopsin ganglion cells in the mouse retina and to highlight their respective roles in non-image-forming and image-forming vision. Although many melanopsin ganglion cell types do project to image-forming brain targets, it is important to note that this is only the first step in determining their influence on image-forming vision. Even so, the visual system has canonically been divided into these two functional realms and melanopsin ganglion cells have begun to challenge the boundary between them, providing an overlap of visual information that is complementary rather than redundant. Further studies on these ganglion cell photoreceptors will no doubt continue to illustrate an ever-expanding role for melanopsin ganglion cells in image-forming vision.
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Affiliation(s)
| | - Maureen E Stabio
- Department of Cell & Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado
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12
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Zele AJ, Adhikari P, Cao D, Feigl B. Melanopsin and Cone Photoreceptor Inputs to the Afferent Pupil Light Response. Front Neurol 2019; 10:529. [PMID: 31191431 PMCID: PMC6540681 DOI: 10.3389/fneur.2019.00529] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 05/03/2019] [Indexed: 11/20/2022] Open
Abstract
Background: Retinal photoreceptors provide the main stage in the mammalian eye for regulating the retinal illumination through changes in pupil diameter, with a small population of melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs) forming the primary afferent pathway for this response. The purpose of this study is to determine how melanopsin interacts with the three cone photoreceptor classes in the human eye to modulate the light-adapted pupil response. Methods: We investigated the independent and combined contributions of the inner and outer retinal photoreceptor inputs to the afferent pupil pathway in participants with trichromatic color vision using a method to independently control the excitations of ipRGCs, cones and rods in the retina. Results: We show that melanopsin-directed stimuli cause a transient pupil constriction generated by cones in the shadow of retinal blood vessels; desensitizing these penumbral cone signals uncovers a signature melanopsin pupil response that includes a longer latency (292 ms) and slower time (4.1x) and velocity (7.7x) to constriction than for cone-directed stimuli, and which remains sustained post-stimulus offset. Compared to melanopsin-mediated pupil responses, the cone photoreceptor-initiated pupil responses are more transient with faster constriction latencies, higher velocities and a secondary constriction at light offset. The combined pupil responses reveal that melanopsin signals are additive with the cone signals. Conclusions: The visual system uses the L–, M–, and S–cone photoreceptor inputs to the afferent pupil pathway to accomplish the tonic modulations of pupil size to changes in image contrast. The inner retinal melanopsin-expressing ipRGCs mediate the longer-term, sustained pupil constriction to set the light-adapted pupil diameter during extended light exposures.
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Affiliation(s)
- Andrew J Zele
- Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, QLD, Australia.,School of Optometry and Vision Science, Queensland University of Technology (QUT), Brisbane, QLD, Australia
| | - Prakash Adhikari
- Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, QLD, Australia.,School of Optometry and Vision Science, Queensland University of Technology (QUT), Brisbane, QLD, Australia
| | - Dingcai Cao
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, United States
| | - Beatrix Feigl
- Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, QLD, Australia.,School of Biomedical Sciences, Queensland University of Technology (QUT), Brisbane, QLD, Australia.,Queensland Eye Institute, Brisbane, QLD, Australia
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13
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La Morgia C, Carelli V, Carbonelli M. Melanopsin Retinal Ganglion Cells and Pupil: Clinical Implications for Neuro-Ophthalmology. Front Neurol 2018; 9:1047. [PMID: 30581410 PMCID: PMC6292931 DOI: 10.3389/fneur.2018.01047] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Accepted: 11/19/2018] [Indexed: 02/02/2023] Open
Abstract
Melanopsin retinal ganglion cells (mRGCs) are intrinsically photosensitive RGCs that mediate many relevant non-image forming functions of the eye, including the pupillary light reflex, through the projections to the olivary pretectal nucleus. In particular, the post-illumination pupil response (PIPR), as evaluated by chromatic pupillometry, can be used as a reliable marker of mRGC function in vivo. In the last years, pupillometry has become a promising tool to assess mRGC dysfunction in various neurological and neuro-ophthalmological conditions. In this review we will present the most relevant findings of pupillometric studies in glaucoma, hereditary optic neuropathies, ischemic optic neuropathies, idiopathic intracranial hypertension, multiple sclerosis, Parkinson's disease, and mood disorders. The use of PIPR as a marker for mRGC function is also proposed for other neurodegenerative disorders in which circadian dysfunction is documented.
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Affiliation(s)
- Chiara La Morgia
- Unità Operativa Complessa Clinica Neurologica, IRCCS Istituto delle Scienze Neurologiche di Bologna, Ospedale Bellaria, Bologna, Italy.,Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Valerio Carelli
- Unità Operativa Complessa Clinica Neurologica, IRCCS Istituto delle Scienze Neurologiche di Bologna, Ospedale Bellaria, Bologna, Italy.,Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Michele Carbonelli
- Unità Operativa Complessa Clinica Neurologica, IRCCS Istituto delle Scienze Neurologiche di Bologna, Ospedale Bellaria, Bologna, Italy
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14
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Zivcevska M, Blakeman A, Lei S, Goltz HC, Wong AMF. Binocular Summation in Postillumination Pupil Response Driven by Melanopsin-Containing Retinal Ganglion Cells. ACTA ACUST UNITED AC 2018; 59:4968-4977. [DOI: 10.1167/iovs.18-24639] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Marija Zivcevska
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Alan Blakeman
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Shaobo Lei
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Herbert C. Goltz
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
- The Krembil Research Institute, Toronto Western Hospital, Toronto, Ontario, Canada
| | - Agnes M. F. Wong
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
- The Krembil Research Institute, Toronto Western Hospital, Toronto, Ontario, Canada
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
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15
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Ostrin LA. The ipRGC-driven pupil response with light exposure and refractive error in children. Ophthalmic Physiol Opt 2018; 38:503-515. [PMID: 30259538 DOI: 10.1111/opo.12583] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 09/08/2018] [Indexed: 11/30/2022]
Abstract
PURPOSE The intrinsically photosensitive retinal ganglion cells (ipRGCs) signal environmental light, control pupil size and entrain circadian rhythm. There is speculation that ipRGCs may be involved in the protective effects of light exposure in myopia. Here, the ipRGC-driven pupil response was evaluated in children and examined with light exposure and refractive error. METHODS Children ages 5-15 years participated. Subjects wore an actigraph device prior to the lab visit for objective measures of light exposure and sleep. For pupillometry, the left eye was dilated and presented with stimuli, and the consensual pupil response was measured in the right eye. Pupil measurements were preceded by 5 min dark adaptation. In Experiment 1 (n = 14), 1 s long wavelength light ('red,' 651 nm, 167 cd m-2 ) and 10 increasing intensities of 1 s short wavelength light ('blue,' 456 nm, 0.167-167 cd m-2 ) were presented with a 60 s interstimulus interval. A piecewise two-segment regression was fit to the stimulus response function to determine the functional melanopsin threshold. Pupil responses were analysed with light exposure over the previous 24 h. For Experiment 2 (n = 42), three 1 s red and three 1 s blue alternating stimuli were presented with a 60 s interstimulus interval. Following an additional 5-min dark adaption, the experiment was repeated. Pupil metrics included peak constriction, the 6 s and 30 s post-illumination response (PIPR), early and late area under the curve (AUC). Following pupil measurements, cycloplegic refractive error and axial length were measured. RESULTS For Experiment 1, PIPR metrics demonstrated a graded response to increasing intensity blue stimuli, with a mean functional melanopsin threshold of 6.2 ± 4.5 cd m-2 (range: 0.84-16.7 cd m-2 ). The 6 s PIPR and early AUC were associated with 24-h light exposure for high intensity stimuli (33.3 and 83.3 cd m-2 , p < 0.005 for both). For Experiment 2, there were no associations between pupil metrics and refractive error. The 6 s PIPR and early AUC to blue stimuli were significantly increased for Trial 2 compared to Trial 1. CONCLUSIONS The ipRGC-driven pupil responses in children were robust and similar to responses previously measured in an adult population. The 6 s PIPR and early AUC to high intensity blue stimuli were associated with previous light exposure. There were no associations between the ipRGC-driven pupil response and refractive status in this cohort.
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Affiliation(s)
- Lisa A Ostrin
- College of Optometry, University of Houston, Houston, USA
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16
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van der Meijden WP, Te Lindert BHW, Ramautar JR, Wei Y, Coppens JE, Kamermans M, Cajochen C, Bourgin P, Van Someren EJW. Sustained effects of prior red light on pupil diameter and vigilance during subsequent darkness. Proc Biol Sci 2018; 285:rspb.2018.0989. [PMID: 30051840 DOI: 10.1098/rspb.2018.0989] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 06/26/2018] [Indexed: 11/12/2022] Open
Abstract
Environmental light can exert potent effects on physiology and behaviour, including pupil size, vigilance and sleep. Previous work showed that these non-image forming effects can last long beyond discontinuation of short-wavelength light exposure. The possible functional effects after switching off long-wavelength light, however, have been insufficiently characterized. In a series of controlled experiments in healthy adult volunteers, we evaluated the effects of five minutes of intense red light on physiology and performance during subsequent darkness. As compared to prior darkness, prior red light induced a subsequent sustained pupil dilation. Prior red light also increased subsequent heart rate and heart rate variability when subjects were asked to perform a sustained vigilance task during the dark exposure. While these changes suggest an increase in the mental effort required for the task, it could not prevent a post-red slowing of response speed. The suggestion that exposure to intense red light affects vigilance during subsequent darkness, was confirmed in a controlled polysomnographic study that indeed showed a post-red facilitation of sleep onset. Our findings suggest the possibility of using red light as a nightcap.
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Affiliation(s)
- Wisse P van der Meijden
- Department of Sleep and Cognition, Netherlands Institute for Neuroscience, 1105 BA Amsterdam, The Netherlands .,Sleep Disorders Center, CHU and FMTS, CNRS-UPR 3212, Institute of Cellular and Integrative Neurosciences, University of Strasbourg, 67084 Strasbourg, France.,Center for Chronobiology, Psychiatric Hospital of the University of Basel, CH-4012 Basel, Switzerland
| | - Bart H W Te Lindert
- Department of Sleep and Cognition, Netherlands Institute for Neuroscience, 1105 BA Amsterdam, The Netherlands
| | - Jennifer R Ramautar
- Department of Sleep and Cognition, Netherlands Institute for Neuroscience, 1105 BA Amsterdam, The Netherlands
| | - Yishul Wei
- Department of Sleep and Cognition, Netherlands Institute for Neuroscience, 1105 BA Amsterdam, The Netherlands
| | - Joris E Coppens
- Department of Sleep and Cognition, Netherlands Institute for Neuroscience, 1105 BA Amsterdam, The Netherlands
| | - Maarten Kamermans
- Department of Retinal Signal Processing, Netherlands Institute for Neuroscience, 1105 BA Amsterdam, The Netherlands.,Department of Neurogenetics, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Christian Cajochen
- Center for Chronobiology, Psychiatric Hospital of the University of Basel, CH-4012 Basel, Switzerland
| | - Patrice Bourgin
- Sleep Disorders Center, CHU and FMTS, CNRS-UPR 3212, Institute of Cellular and Integrative Neurosciences, University of Strasbourg, 67084 Strasbourg, France
| | - Eus J W Van Someren
- Department of Sleep and Cognition, Netherlands Institute for Neuroscience, 1105 BA Amsterdam, The Netherlands.,Departments of Integrative Neurophysiology and Psychiatry, Center for Neurogenomics and Cognitive Research (CNCR), Neuroscience Campus Amsterdam, VU University and Medical Center, 1081 HL Amsterdam, The Netherlands
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17
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Douglas RH. The pupillary light responses of animals; a review of their distribution, dynamics, mechanisms and functions. Prog Retin Eye Res 2018; 66:17-48. [PMID: 29723580 DOI: 10.1016/j.preteyeres.2018.04.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 04/24/2018] [Accepted: 04/25/2018] [Indexed: 11/28/2022]
Abstract
The timecourse and extent of changes in pupil area in response to light are reviewed in all classes of vertebrate and cephalopods. Although the speed and extent of these responses vary, most species, except the majority of teleost fish, show extensive changes in pupil area related to light exposure. The neuromuscular pathways underlying light-evoked pupil constriction are described and found to be relatively conserved, although the precise autonomic mechanisms differ somewhat between species. In mammals, illumination of only one eye is known to cause constriction in the unilluminated pupil. Such consensual responses occur widely in other animals too, and their function and relation to decussation of the visual pathway is considered. Intrinsic photosensitivity of the iris muscles has long been known in amphibia, but is in fact widespread in other animals. The functions of changes in pupil area are considered. In the majority of species, changes in pupil area serve to balance the conflicting demands of high spatial acuity and increased sensitivity in different light levels. In the few teleosts in which pupil movements occur they do not serve a visual function but play a role in camouflaging the eye of bottom-dwelling species. The occurrence and functions of the light-independent changes in pupil size displayed by many animals are also considered. Finally, the significance of the variations in pupil shape, ranging from circular to various orientations of slits, ovals, and other shapes, is discussed.
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Affiliation(s)
- Ronald H Douglas
- Division of Optometry & Visual Science City, University of London, Northampton Square, London, EC1V 0HB, United Kingdom.
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18
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Lee S, Uchiyama Y, Shimomura Y, Katsuura T. Subadditive responses to extremely short blue and green pulsed light on visual evoked potentials, pupillary constriction and electroretinograms. J Physiol Anthropol 2017; 36:39. [PMID: 29149913 PMCID: PMC5693602 DOI: 10.1186/s40101-017-0156-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 11/14/2017] [Indexed: 01/18/2023] Open
Abstract
Background The simultaneous exposure to blue and green light was reported to result in less melatonin suppression than monochromatic exposure to blue or green light. Here, we conducted an experiment using extremely short blue- and green-pulsed light to examine their visual and nonvisual effects on visual evoked potentials (VEPs), pupillary constriction, electroretinograms (ERGs), and subjective evaluations. Methods Twelve adult male subjects were exposed to three light conditions: blue-pulsed light (2.5-ms pulse width), green-pulsed light (2.5-ms pulse width), and simultaneous blue- and green-pulsed light with white background light. We measured the subject’s pupil diameter three times in each condition. Then, after 10 min of rest, the subject was exposed to the same three light conditions. We measured the averaged ERG and VEP during 210 pulsed-light exposures in each condition. We also determined subjective evaluations using a visual analog scale (VAS) method. Results The pupillary constriction during the simultaneous exposure to blue- and green-pulsed light was significantly lower than that during the blue-pulsed light exposure despite the double irradiance intensity of the combination. We also found that the b/|a| wave of the ERGs during the simultaneous exposure to blue- and green-pulsed light was lower than that during the blue-pulsed light exposure. We confirmed the subadditive response to pulsed light on pupillary constriction and ERG. However, the P100 of the VEPs during the blue-pulsed light were smaller than those during the simultaneous blue- and green-pulsed light and green-pulsed light, indicating that the P100 amplitude might depend on the luminance of light. Conclusions Our findings demonstrated the effect of the subadditive response to extremely short pulsed light on pupillary constriction and ERG responses. The effects on ipRGCs by the blue-pulsed light exposure are apparently reduced by the simultaneous irradiation of green light. The blue versus yellow (b/y) bipolar cells in the retina might be responsible for this phenomenon.
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Affiliation(s)
- Soomin Lee
- Center for Environment, Health and Sciences, Chiba University, 6-2-1 Kashiwanoha, Kashiwa, Chiba, 277-0882, Japan.
| | - Yuria Uchiyama
- Graduate School of Engineering, Chiba University, Chiba, Japan
| | | | - Tetsuo Katsuura
- Graduate School of Engineering, Chiba University, Chiba, Japan
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19
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Lee S, Muto N, Shimomura Y, Katsuura T. Human pupillary light reflex during successive irradiation with 1-ms blue- and green-pulsed light. J Physiol Anthropol 2017; 36:37. [PMID: 29041976 PMCID: PMC5646119 DOI: 10.1186/s40101-017-0153-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/10/2017] [Indexed: 11/16/2022] Open
Abstract
Background In the human retina, the contribution of intrinsically photosensitive retinal ganglion cells (ipRGCs) to the regulation of the pupillary response remains poorly understood. The objective of the current study was to determine the response dynamics of the pupillary light reflex to short, successive pulses of light. In order to better assess the roles of ipRGCs and cones, we used pulses of blue and green light. Methods Each participant was exposed to 1-ms blue (466 nm) and/or green (527 nm) light pulses simultaneously or separately, with inter-stimulus intervals (ISIs) of 0, 250, 500, 750, or 1000 ms. Pupil diameter was measured using an infrared camera system. Results We found that human pupillary light responses during simultaneous irradiation or successive irradiation with ISIs ≤ 250 ms were equivalent, though successive irradiation of blue- and green-pulsed light with ISIs ≥ 500 ms induced markedly increased pupillary constriction. Conclusions We propose that this result may be related to cell hyperpolarization that occurs in the retina just after the first light stimulus is turned off, with the threshold for this effect being between 250 and 500 ms in the human retina.
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Affiliation(s)
- Soomin Lee
- Center for Environment, Health and Field Sciences, Chiba University, 6-2-1, Kashiwanoha, Kashiwa, 277-0882, Japan.
| | - Naoko Muto
- Faculty of Engineering, Chiba University, 1-33, Yayoi-cho, Inage-ku, Chiba, 263-8522, Japan
| | - Yoshihiro Shimomura
- Graduate School of Engineering, Chiba University, 1-33, Yayoi-cho, Inage-ku, Chiba, 263-8522, Japan
| | - Tetsuo Katsuura
- Graduate School of Engineering, Chiba University, 1-33, Yayoi-cho, Inage-ku, Chiba, 263-8522, Japan
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20
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Ostrin LA, Abbott KS, Queener HM. Attenuation of short wavelengths alters sleep and the ipRGC pupil response. Ophthalmic Physiol Opt 2017; 37:440-450. [PMID: 28656675 DOI: 10.1111/opo.12385] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Accepted: 03/29/2017] [Indexed: 11/29/2022]
Abstract
PURPOSE Exposure to increasing amounts of artificial light during the night may contribute to the high prevalence of reported sleep dysfunction. Release of the sleep hormone melatonin is mediated by the intrinsically photosensitive retinal ganglion cells (ipRGCs). This study sought to investigate whether melatonin level and sleep quality can be modulated by decreasing night-time input to the ipRGCs. METHODS Subjects (ages 17-42, n = 21) wore short wavelength-blocking glasses prior to bedtime for 2 weeks. The ipRGC-mediated post illumination pupil response was measured before and after the experimental period. Stimulation was presented with a ganzfeld stimulator, including one-second and five-seconds of long and short wavelength light, and the pupil was imaged with an infrared camera. Pupil diameter was measured before, during and for 60 s following stimulation, and the six-second and 30 s post illumination pupil response and area under the curve following light offset were determined. Subjects wore an actigraph device for objective measurements of activity, light exposure, and sleep. Saliva samples were collected to assess melatonin content. The Pittsburgh Sleep Quality Index (PSQI) was administered to assess subjective sleep quality. RESULTS Subjects wore the blue-blocking glasses 3:57 ± 1:03 h each night. After the experimental period, the pupil showed a slower redilation phase, resulting in a significantly increased 30 s post illumination pupil response to one-second short wavelength light, and decreased area under the curve for one and five-second short wavelength light, when measured at the same time of day as baseline. Night time melatonin increased from 16.1 ± 7.5 pg mL-1 to 25.5 ± 10.7 pg mL-1 (P < 0.01). Objectively measured sleep duration increased 24 min, from 408.7 ± 44.9 to 431.5 ± 42.9 min (P < 0.001). Mean PSQI score improved from 5.6 ± 2.9 to 3.0 ± 2.2. CONCLUSIONS The use of short wavelength-blocking glasses at night increased subjectively measured sleep quality and objectively measured melatonin levels and sleep duration, presumably as a result of decreased night-time stimulation of ipRGCs. Alterations in the ipRGC-driven pupil response suggest a shift in circadian phase. Results suggest that minimising short wavelength light following sunset may help in regulating sleep patterns.
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Affiliation(s)
- Lisa A Ostrin
- University of Houston College of Optometry, Houston, USA
| | - Kaleb S Abbott
- University of Houston College of Optometry, Houston, USA
| | - Hope M Queener
- University of Houston College of Optometry, Houston, USA
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21
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Charng J, Jacobson SG, Heon E, Roman AJ, McGuigan DB, Sheplock R, Kosyk MS, Swider M, Cideciyan AV. Pupillary Light Reflexes in Severe Photoreceptor Blindness Isolate the Melanopic Component of Intrinsically Photosensitive Retinal Ganglion Cells. Invest Ophthalmol Vis Sci 2017; 58:3215-3224. [PMID: 28660274 PMCID: PMC5490362 DOI: 10.1167/iovs.17-21909] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Purpose Pupillary light reflex (PLR) is driven by outer retinal photoreceptors and by melanopsin-expressing intrinsically photosensitive retinal ganglion cells of the inner retina. To isolate the melanopic component, we studied patients with severe vision loss due to Leber congenital amaurosis (LCA) caused by gene mutations acting on the outer retina. Methods Direct PLR was recorded in LCA patients (n = 21) with known molecular causation and severe vision loss. Standard stimuli (2.5 log scot-cd.m−2; ∼13 log quanta.cm−2.s−1; achromatic full-field) with 0.1- or 5-second duration were used in all patients. Additional recordings were performed with higher luminance (3.9 log scot-cd.m−2) in a subset of patients. Results The LCA patients showed no detectable PLR to the standard stimulus with short duration. With longer-duration stimuli, a PLR was detectable in the majority (18/21) of patients. The latency of the PLR was 2.8 ± 1.3 seconds, whereas normal latency was 0.19 ± 0.02 seconds. Peak contraction amplitude in patients was 1.1 ± 0.9 mm at 6.2 ± 2.3 seconds, considerably different from normal amplitude of 4.2 ± 0.4 mm at 3.0 ± 0.4 seconds. Recordings with higher luminance demonstrated that PLRs in severe LCA could also be evoked with short-duration stimuli. Conclusions The PLR in severe LCA patients likely represents the activation of the melanopic circuit in isolation from rod and cone input. Knowledge of the properties of the human melanopic PLR allows not only comparison to those in animal models but also serves to define the fidelity of postretinal transmission in clinical trials targeting patients with no outer retinal function.
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Affiliation(s)
- Jason Charng
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Samuel G Jacobson
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Elise Heon
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Alejandro J Roman
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - David B McGuigan
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Rebecca Sheplock
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Mychajlo S Kosyk
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Malgorzata Swider
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Artur V Cideciyan
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
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22
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Effects of photopic and cirtopic illumination on steady state pupil sizes. Vision Res 2017; 137:24-28. [PMID: 28688906 DOI: 10.1016/j.visres.2017.02.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 02/14/2017] [Accepted: 02/24/2017] [Indexed: 11/21/2022]
Abstract
The conventional view was that cones are responsible for pupil constriction in photopic lighting conditions. With the discovery of intrinsically photosensitive retinal ganglion cells (ipRGC), it was found that signals from ipRGCs along with cones mediated the pupil light reflex in photopic lighting conditions. Although both signals contributed, it was unclear how these signals were summed. In the work reported here, steady-state pupil size was measured with an infrared camera under LED lighting conditions with different color temperatures and luminance. A formula was then derived for pupil size according to the linear summation of cirtopic and photopic luminance. This formula allowed direct calculations to predict pupil size well when LED photopic luminance ranged from about 50cd/m2 to 300cd/m2, which is the general luminance level range for computer and smartphone screens.
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23
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The diagnostic accuracy of chromatic pupillary light responses in diseases of the outer and inner retina. Graefes Arch Clin Exp Ophthalmol 2016; 255:519-527. [DOI: 10.1007/s00417-016-3496-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 08/04/2016] [Accepted: 09/13/2016] [Indexed: 11/26/2022] Open
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Lee S, Ishibashi S, Shimomura Y, Katsuura T. Effect of simultaneous exposure to extremely short pulses of blue and green light on human pupillary constriction. J Physiol Anthropol 2016; 35:20. [PMID: 27580696 PMCID: PMC5006526 DOI: 10.1186/s40101-016-0109-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 08/19/2016] [Indexed: 11/10/2022] Open
Affiliation(s)
- Soomin Lee
- Center for Environment, Health and Field Sciences, Chiba University, 6-2-1, Kashiwanoha, Kashiwa, 277-0882, Japan.
| | - Shougo Ishibashi
- Graduate School of Engineering, Chiba University, Chiba, Japan.,Present address: East Japan Railway Company, Tokyo, Japan
| | | | - Tetsuo Katsuura
- Graduate School of Engineering, Chiba University, Chiba, Japan
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Adhikari P, Feigl B, Zele AJ. Rhodopsin and Melanopsin Contributions to the Early Redilation Phase of the Post-Illumination Pupil Response (PIPR). PLoS One 2016; 11:e0161175. [PMID: 27548480 PMCID: PMC4993463 DOI: 10.1371/journal.pone.0161175] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 08/01/2016] [Indexed: 12/03/2022] Open
Abstract
Melanopsin expressing intrinsically photosensitive Retinal Ganglion Cells (ipRGCs) entirely control the post-illumination pupil response (PIPR) from 6 s post-stimulus to the plateau during redilation after light offset. However, the photoreceptor contributions to the early redilation phase of the PIPR (< 6 s post-stimulus) have not been reported. Here, we evaluated the photoreceptor contributions to the early phase PIPR (0.6 s to 5.0 s) by measuring the spectral sensitivity of the criterion PIPR amplitude in response to 1 s light pulses at five narrowband stimulus wavelengths (409, 464, 508, 531 and 592 nm). The retinal irradiance producing a criterion PIPR was normalised to the peak and fitted by either a single photopigment nomogram or the combined melanopsin and rhodopsin spectral nomograms with the +L+M cone photopic luminous efficiency (Vλ) function. We show that the PIPR spectral sensitivity at times ≥ 1.7 s after light offset is best described by the melanopsin nomogram. At times < 1.7 s, the peak PIPR sensitivity shifts to longer wavelengths (range: 482 to 498 nm) and is best described by the combined photoreceptor nomogram, with major contributions from melanopsin and rhodopsin. This first report of melanopsin and rhodopsin contributions to the early phase PIPR is in line with the electrophysiological findings of ipRGC and rod signalling after the cessation of light stimuli and provides a cut-off time for isolating photoreceptor specific function in healthy and diseased eyes.
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Affiliation(s)
- Prakash Adhikari
- Visual Science and Medical Retina Laboratories, Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Queensland, Australia
- School of Optometry and Vision Science, Queensland University of Technology (QUT), Brisbane, Queensland, Australia
| | - Beatrix Feigl
- Visual Science and Medical Retina Laboratories, Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Queensland, Australia
- School of Biomedical Sciences, Queensland University of Technology (QUT), Brisbane, Queensland, Australia
- Queensland Eye Institute, Brisbane, Queensland, Australia
| | - Andrew J. Zele
- Visual Science and Medical Retina Laboratories, Institute of Health and Biomedical Innovation, Queensland University of Technology (QUT), Brisbane, Queensland, Australia
- School of Optometry and Vision Science, Queensland University of Technology (QUT), Brisbane, Queensland, Australia
- * E-mail:
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Nakayama M, Nowak W, Ishikawa H, Asakawa K, Ichibe Y. Discovering irregular pupil light responses to chromatic stimuli using waveform shapes of pupillograms. EURASIP JOURNAL ON BIOINFORMATICS & SYSTEMS BIOLOGY 2014; 2014:18. [PMID: 28194168 PMCID: PMC5270378 DOI: 10.1186/s13637-014-0018-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Accepted: 07/02/2014] [Indexed: 11/10/2022]
Abstract
Background The waveforms of the pupillary light reflex (PLR) can be analyzed in a diagnostic test that allows for differentiation between disorders affecting photoreceptors and disorders affecting retinal ganglion cells, using various signal processing techniques. This procedure has been used on both healthy subjects and patients with age-related macular degeneration (AMD), as a simple diagnostic procedure is required for diagnosis. Results The Fourier descriptor technique is used to extract the features of PLR waveform shapes of pupillograms and their amplitudes. To detect those patients affected by AMD using the extracted features, multidimensional scaling (MDS) and clustering techniques were used to emphasize stimuli and subject differences. The detection performance of AMD using the features and the MDS technique shows only a qualitative tendency, however. To evaluate the detection performance quantitatively, a set of combined features was created to evaluate characteristics of the PLR waveform shapes in detail. Classification performance was compared across three categories (AMD patients, aged, and healthy subjects) using the Random Forest method, and weighted values were optimized using variations of the classification error rates. The results show that the error rates for healthy pupils and AMD-affected pupils were low when the value of the coefficient for a combination of PLR amplitudes and features of waveforms was optimized as 1.5. However, the error rates for patients with age-affected eyes was not low. Conclusions A classification procedure for AMD patients has been developed using the features of PLR waveform shapes and their amplitudes. The results show that the error rates for healthy PLRs and AMD PLRs were low when the Random Forest method was used to produce the classification. The classification of pupils of patients with age-affected eyes should be carefully considered in order to produce optimum results. Electronic supplementary material The online version of this article (doi:10.1186/s13637-014-0018-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Minoru Nakayama
- Department of Human System Science, Tokyo Institute of Technology, Ookayama, Meguro, Tokyo, 152-8552 Japan
| | - Wioletta Nowak
- Institute of Biomedical Engineering and Instrumentation, Wroclaw University of Technology, Wroclaw, 50-370 Poland
| | - Hitoshi Ishikawa
- School of Allied Health Sciences, Kitasato University, Kitasato, Minami, Sagamihara, 252-0373 Japan
| | - Ken Asakawa
- School of Allied Health Sciences, Kitasato University, Kitasato, Minami, Sagamihara, 252-0373 Japan
| | - Yoshiaki Ichibe
- School of Medicine, Kitasato University, Kitasato, Minami, Sagamihara, 252-0373 Japan
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Ozeki N, Yuki K, Shiba D, Tsubota K. Pupillographic evaluation of relative afferent pupillary defect in glaucoma patients. Br J Ophthalmol 2013; 97:1538-42. [DOI: 10.1136/bjophthalmol-2013-303825] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Katsuura T, Ochiai Y, Senoo T, Lee S, Takahashi Y, Shimomura Y. Effects of blue pulsed light on human physiological functions and subjective evaluation. J Physiol Anthropol 2012; 31:23. [PMID: 22943428 PMCID: PMC3443645 DOI: 10.1186/1880-6805-31-23] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 08/17/2012] [Indexed: 11/24/2022] Open
Abstract
Background It has been assumed that light with a higher irradiance of pulsed blue light has a much greater influence than that of light with a lower irradiance of steady blue light, although they have the same multiplication value of irradiance and duration. We examined the non-visual physiological effects of blue pulsed light, and determined whether it is sensed visually as being blue. Findings Seven young male volunteers participated in the study. We placed a circular screen (diameter 500 mm) in front of the participants and irradiated it using blue and/or white light-emitting diodes (LEDs), and we used halogen lamps as a standard illuminant. We applied three steady light conditions of white LED (F0), blue LED + white LED (F10), and blue LED (F100), and a blue pulsed light condition of a 100-μs pulse width with a 10% duty ratio (P10). The irradiance of all four conditions at the participant's eye level was almost the same, at around 12 μW/cm2. We measured their pupil diameter, recorded electroencephalogram readings and Kwansei Gakuin Sleepiness Scale score, and collected subjective evaluations. The subjective bluish score under the F100 condition was significantly higher than those under other conditions. Even under the P10 condition with a 10% duty ratio of blue pulsed light and the F10 condition, the participant did not perceive the light as bluish. Pupillary light response under the P10 pulsed light condition was significantly greater than under the F10 condition, even though the two conditions had equal blue light components. Conclusions The pupil constricted under the blue pulsed light condition, indicating a non-visual effect of the lighting, even though the participants did not perceive the light as bluish.
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Affiliation(s)
- Tetsuo Katsuura
- Graduate School of Engineering, Chiba University, Chiba, Japan.
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Herbst K, Sander B, Lund-Andersen H, Broendsted AE, Kessel L, Hansen MS, Kawasaki A. Intrinsically photosensitive retinal ganglion cell function in relation to age: a pupillometric study in humans with special reference to the age-related optic properties of the lens. BMC Ophthalmol 2012; 12:4. [PMID: 22471313 PMCID: PMC3411473 DOI: 10.1186/1471-2415-12-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Accepted: 04/03/2012] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND The activity of melanopsin containing intrinsically photosensitive ganglion retinal cells (ipRGC) can be assessed by a means of pupil responses to bright blue (appr.480 nm) light. Due to age related factors in the eye, particularly, structural changes of the lens, less light reaches retina. The aim of this study was to examine how age and in vivo measured lens transmission of blue light might affect pupil light responses, in particular, mediated by the ipRGC. METHODS Consensual pupil responses were explored in 44 healthy subjects aged between 26 and 68 years. A pupil response was recorded to a continuous 20 s light stimulus of 660 nm (red) or 470 nm (blue) both at 300 cd/m2 intensity (14.9 and 14.8 log photons/cm2/s, respectively). Additional recordings were performed using four 470 nm stimulus intensities of 3, 30, 100 and 300 cd/m2. The baseline pupil size was measured in darkness and results were adjusted for the baseline pupil and gender. The main outcome parameters were maximal and sustained pupil contraction amplitudes and the postillumination response assessed as area under the curve (AUC) over two time-windows: early (0-10 s after light termination) and late (10-30 s after light termination). Lens transmission was measured with an ocular fluorometer. RESULTS The sustained pupil contraction and the early poststimulus AUC correlated positively with age (p=0.02, p=0.0014, respectively) for the blue light stimulus condition only.The maximal pupil contraction amplitude did not correlate to age either for bright blue or red light stimulus conditions.Lens transmission decreased linearly with age (p<0.0001). The pupil response was stable or increased with decreasing transmission, though only significantly for the early poststimulus AUC to 300 cd/m2 light (p=0.02). CONCLUSIONS Age did not reduce, but rather enhance pupil responses mediated by ipRGC. The age related decrease of blue light transmission led to similar results, however, the effect of age was greater on these pupil responses than that of the lens transmission. Thus there must be other age related factors such as lens scatter and/or adaptive processes influencing the ipRGC mediated pupil response enhancement observed with advancing age.
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Affiliation(s)
- Kristina Herbst
- Department of Ophthalmology, Glostrup Hospital, Ndr. Ringvej 57, 2600 Glostrup, Copenhagen, Denmark
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30
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Viénot F, Brettel H, Dang TV, Le Rohellec J. Domain of metamers exciting intrinsically photosensitive retinal ganglion cells (ipRGCs) and rods. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2012; 29:A366-A376. [PMID: 22330402 DOI: 10.1364/josaa.29.00a366] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Any stimulus can be described as composed of two components-a fundamental color stimulus that controls the three cone responses and a metameric black that has no effect on cones but can drive photoreceptors other than cones [e.g., rods and melanopsin expressing retinal ganglion cells (ipRGCs)]. The Cohen and Kappauf [Am. J. Psychol. 95, 537 (1982)] method is extended to calculate the black metamer basis for a limited set of band spectra. Using seven colored LEDs, the method is exploited to produce real metamer illuminations that stimulate in parallel melanopsin expressing ipRGCs and rods, at most or at least. We have verified that the pupil diameter increases when the ipRGC and rod excitation is at a minimum. For 14 observers, the average relative increase is 12%.
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Affiliation(s)
- Françoise Viénot
- Centre de Recherche sur la Conservation des Collections, Muséum National d’Histoire Naturelle, 36 rue Geoffroy Saint-Hilaire, F-75005 Paris, France.
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Ishikawa H, Onodera A, Asakawa K, Nakadomari S, Shimizu K. Effects of selective-wavelength block filters on pupillary light reflex under red and blue light stimuli. Jpn J Ophthalmol 2012; 56:181-6. [PMID: 22219036 DOI: 10.1007/s10384-011-0116-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2011] [Accepted: 11/22/2011] [Indexed: 10/14/2022]
Abstract
PURPOSE To investigate at which wavelength melanopsin-containing retinal ganglion cells (mRGCs) depolarize and how they affect pupillary constriction induced by light stimulation in humans. METHODS The pupil light reflex was evaluated for 30 normal subjects by use of an infrared pupillometer. Blue light stimulation (470 nm) and red light stimulation (635 nm) of 100 cd/m(2) were selected. Selective-wavelength block filters which can selectively remove the wavelengths 440 and 470 nm were used. Visual tests were also performed to observe the effects of the filters on visual acuity, color vision, and contrast sensitivity. RESULTS The pupil transiently constricts and then settles toward a steady-state diameter when stimulated with the light. When the 470-nm-block filter was worn, the sustained phase of pupillary constriction, thought to be mediated by the mRGCs, was not stable but there was no effect on the initial phase of pupillary constriction under blue light stimulation. Visual acuity, color vision, and contrast sensitivity were not affected by the 470-nm-block filter. CONCLUSIONS These results suggest that the mRGC in humans may respond to 470-nm-wavelength light at 100 cd/m(2), and there is a possibility of affecting the sustained phase of the light reflex without changing visual performance.
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Affiliation(s)
- Hitoshi Ishikawa
- School of Allied Health Sciences, Kitasato University, 1-15-1 Kitasato, Minamiku, Sagamihara, Kanagawa, 252-0373, Japan.
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Dunlop C. Ipsilateral pupil dilation associated with unilateral intermittent exotropia: a new observation. Clin Exp Ophthalmol 2011; 39:839-41. [PMID: 21794049 DOI: 10.1111/j.1442-9071.2011.02659.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Park JC, Moura AL, Raza AS, Rhee DW, Kardon RH, Hood DC. Toward a clinical protocol for assessing rod, cone, and melanopsin contributions to the human pupil response. Invest Ophthalmol Vis Sci 2011; 52:6624-35. [PMID: 21743008 DOI: 10.1167/iovs.11-7586] [Citation(s) in RCA: 162] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE. To better understand the relative contributions of rod, cone, and melanopsin to the human pupillary light reflex (PLR) and to determine the optimal conditions for assessing the health of the rod, cone, and melanopsin pathways with a relatively brief clinical protocol. METHODS. PLR was measured with an eye tracker, and stimuli were controlled with a Ganzfeld system. In experiment 1, 2.5 log cd/m(2) red (640 ± 10 nm) and blue (467 ± 17 nm) stimuli of various durations were presented after dark adaptation. In experiments 2 and 3, 1-second red and blue stimuli were presented at different intensity levels in the dark (experiment 2) or on a 0.78 log cd/m(2) blue background (experiment 3). Based on the results of experiments 1 to 3, a clinical protocol was designed and tested on healthy control subjects and patients with retinitis pigmentosa and Leber's congenital amaurosis. RESULTS. The duration for producing the optimal melanopsin-driven sustained pupil response after termination of an intense blue stimulus was 1 second. PLR rod- and melanopsin-driven components are best studied with low- and high-intensity flashes, respectively, presented in the dark (experiment 2). A blue background suppressed rod and melanopsin responses, making it easy to assess the cone contribution with a red flash (experiment 3). With the clinical protocol, robust melanopsin responses could be seen in patients with few or no contributions from the rods and cones. CONCLUSIONS. It is possible to assess the rod, cone, and melanopsin contributions to the PLR with blue flashes at two or three intensity levels in the dark and one red flash on a blue background.
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Affiliation(s)
- Jason C Park
- Departments of Psychology, Columbia University, New York, USA
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34
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Tsujimura SI, Tokuda Y. Delayed response of human melanopsin retinal ganglion cells on the pupillary light reflex. Ophthalmic Physiol Opt 2011; 31:469-79. [DOI: 10.1111/j.1475-1313.2011.00846.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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35
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McDougal DH, Gamlin PD. The influence of intrinsically-photosensitive retinal ganglion cells on the spectral sensitivity and response dynamics of the human pupillary light reflex. Vision Res 2011; 50:72-87. [PMID: 19850061 DOI: 10.1016/j.visres.2009.10.012] [Citation(s) in RCA: 161] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 10/12/2009] [Accepted: 10/13/2009] [Indexed: 11/15/2022]
Abstract
Historically, it was assumed that the light-evoked neural signals driving the human pupillary light reflex (PLR) originated exclusively from rod and cone photoreceptors. However, a novel melanopsin-containing photoreceptive cell class has recently been discovered in the mammalian retina. These intrinsically-photosensitive retinal ganglion cells (ipRGCs) project to the pretectum, the retinorecipient area of the brain responsible for the PLR. This study was therefore designed to examine the relative contribution of rod, cone and the melanopsin photoresponses of ipRGCs to the human PLR. We establish that the melanopsin photoresponse of ipRGCs contributes significantly to the maintenance of half maximal pupilloconstriction in response to light stimuli of 30s or longer, even at low photopic irradiances. Furthermore, we show that the melanopsin photoresponse contributes significantly to three-quarter maximal pupilloconstriction in response to light stimuli as short as 2s. We also demonstrate that cone photoresponses driving pupilloconstriction adapt considerably and contribute little after 30s, but rod photoresponses adapt less and contribute significantly to the maintenance of pupilloconstriction in response to steady-state light stimuli at irradiance levels which are below the threshold of the melanopsin photoresponse.
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Affiliation(s)
- David H McDougal
- Laboratory of Autonomic Neurosciences, Pennington Biomedical Research, Center, 6400 Perkins Road, Baton Rouge, LA 70808, United States
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36
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Dearworth JR, Selvarajah BP, Kalman RA, Lanzone AJ, Goch AM, Boyd AB, Goldberg LA, Cooper LJ. A mammalian melanopsin in the retina of a fresh water turtle, the red-eared slider (Trachemys scripta elegans). Vision Res 2011; 51:288-95. [DOI: 10.1016/j.visres.2010.10.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2010] [Revised: 10/19/2010] [Accepted: 10/21/2010] [Indexed: 10/18/2022]
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37
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Sipe GO, Dearworth JR, Selvarajah BP, Blaum JF, Littlefield TE, Fink DA, Casey CN, McDougal DH. Spectral sensitivity of the photointrinsic iris in the red-eared slider turtle (Trachemys scripta elegans). Vision Res 2011; 51:120-30. [DOI: 10.1016/j.visres.2010.10.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Revised: 10/01/2010] [Accepted: 10/07/2010] [Indexed: 10/18/2022]
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Abstract
Life on earth is subject to alternating cycles of day and night imposed by the rotation of the earth. Consequently, living things have evolved photodetective systems to synchronize their physiology and behavior with the external light-dark cycle. This form of photodetection is unlike the familiar "image vision," in that the basic information is light or darkness over time, independent of spatial patterns. "Nonimage" vision is probably far more ancient than image vision and is widespread in living species. For mammals, it has long been assumed that the photoreceptors for nonimage vision are also the textbook rods and cones. However, recent years have witnessed the discovery of a small population of retinal ganglion cells in the mammalian eye that express a unique visual pigment called melanopsin. These ganglion cells are intrinsically photosensitive and drive a variety of nonimage visual functions. In addition to being photoreceptors themselves, they also constitute the major conduit for rod and cone signals to the brain for nonimage visual functions such as circadian photoentrainment and the pupillary light reflex. Here we review what is known about these novel mammalian photoreceptors.
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Affiliation(s)
- Michael Tri Hoang Do
- Solomon H. Snyder Department of Neuroscience and Center for Sensory Biology, Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA
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39
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Viénot F, Bailacq S, Rohellec JL. The effect of controlled photopigment excitations on pupil aperture. Ophthalmic Physiol Opt 2010; 30:484-91. [DOI: 10.1111/j.1475-1313.2010.00754.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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40
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Lall GS, Revell VL, Momiji H, Al Enezi J, Altimus CM, Güler AD, Aguilar C, Cameron MA, Allender S, Hankins MW, Lucas RJ. Distinct contributions of rod, cone, and melanopsin photoreceptors to encoding irradiance. Neuron 2010; 66:417-28. [PMID: 20471354 PMCID: PMC2875410 DOI: 10.1016/j.neuron.2010.04.037] [Citation(s) in RCA: 218] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/19/2010] [Indexed: 12/04/2022]
Abstract
Photoreceptive, melanopsin-expressing retinal ganglion cells (mRGCs) encode ambient light (irradiance) for the circadian clock, the pupillomotor system, and other influential behavioral/physiological responses. mRGCs are activated both by their intrinsic phototransduction cascade and by the rods and cones. However, the individual contribution of each photoreceptor class to irradiance responses remains unclear. We address this deficit using mice expressing human red cone opsin, in which rod-, cone-, and melanopsin-dependent responses can be identified by their distinct spectral sensitivity. Our data reveal an unexpectedly important role for rods. These photoreceptors define circadian responses at very dim “scotopic” light levels but also at irradiances at which pattern vision relies heavily on cones. By contrast, cone input to irradiance responses dissipates following light adaptation to the extent that these receptors make a very limited contribution to circadian and pupillary light responses under these conditions. Our data provide new insight into retinal circuitry upstream of mRGCs and optimal stimuli for eliciting irradiance responses.
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Affiliation(s)
- Gurprit S Lall
- Faculty of Life Sciences, AV Hill Building, University of Manchester, Manchester M13 9PT, UK
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41
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Tsujimura SI, Ukai K, Ohama D, Nuruki A, Yunokuchi K. Contribution of human melanopsin retinal ganglion cells to steady-state pupil responses. Proc Biol Sci 2010; 277:2485-92. [PMID: 20375057 DOI: 10.1098/rspb.2010.0330] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The recent discovery of melanopsin-containing retinal ganglion cells (mRGCs) has led to a fundamental reassessment of non-image forming processing, such as circadian photoentrainment and the pupillary light reflex. In the conventional view of retinal physiology, rods and cones were assumed to be the only photoreceptors in the eye and were, therefore, considered responsible for non-image processing. However, signals from mRGCs contribute to this non-image forming processing along with cone-mediated luminance signals; although both signals contribute, it is unclear how these signals are summed. We designed and built a novel multi-primary stimulation system to stimulate mRGCs independently of other photoreceptors using a silent-substitution technique within a bright steady background. The system allows direct measurements of pupillary functions for mRGCs and cones. We observed a significant change in steady-state pupil diameter when we varied the excitation of mRGC alone, with no change in luminance and colour. Furthermore, the change in pupil diameter induced by mRGCs was larger than that induced by a variation in luminance alone: that is, for a bright steady background, the mRGC signals contribute to the pupillary pathway by a factor of three times more than the L- and M-cone signals.
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Affiliation(s)
- Sei-ichi Tsujimura
- Department of Information Science and Biomedical Engineering, Kagoshima University, Kagoshima, Japan.
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42
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Consensual pupillary light response in the red-eared slider turtle (Trachemys scripta elegans). Vision Res 2010; 50:598-605. [DOI: 10.1016/j.visres.2010.01.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Revised: 01/07/2010] [Accepted: 01/07/2010] [Indexed: 11/22/2022]
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43
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Sustained pupillary constrictions mediated by an L- and M-cone opponent process. Vision Res 2010; 50:489-96. [PMID: 20060405 DOI: 10.1016/j.visres.2010.01.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2009] [Revised: 12/11/2009] [Accepted: 01/04/2010] [Indexed: 11/30/2022]
Abstract
We show that irradiance-coding alone cannot explain the sustained pupillary constrictions evoked by chromatic and luminance variations in a stimulus. For example, stimulus modulations that decremented the contrasts in L- and M-cones as well as rods and melanopsin photoreceptors produced sustained constrictions rather than the predicted dilations. Although the sustained responses are unidirectional, we confirm that they are at least partially mediated by an L- and M-cone opponent interaction. We discuss the implications of sustained unidirectional chromatic responses in view of the function of the pupil to improve the clarity of vision.
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Smith MR, Eastman CI. Phase delaying the human circadian clock with blue-enriched polychromatic light. Chronobiol Int 2009; 26:709-25. [PMID: 19444751 DOI: 10.1080/07420520902927742] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The human circadian system is maximally sensitive to short-wavelength (blue) light. In a previous study we found no difference between the magnitude of phase advances produced by bright white versus bright blue-enriched light using light boxes in a practical protocol that could be used in the real world. Since the spectral sensitivity of the circadian system may vary with a circadian rhythm, we tested whether the results of our recent phase-advancing study hold true for phase delays. In a within-subjects counterbalanced design, this study tested whether bright blue-enriched polychromatic light (17000 K, 4000 lux) could produce larger phase delays than bright white light (4100 K, 5000 lux) of equal photon density (4.2x10(15) photons/cm(2)/sec). Healthy young subjects (n = 13) received a 2 h phase delaying light pulse before bedtime combined with a gradually delaying sleep/dark schedule on each of 4 consecutive treatment days. On the first treatment day the light pulse began 3 h after the dim light melatonin onset (DLMO). An 8 h sleep episode began at the end of the light pulse. Light treatment and the sleep schedule were delayed 2 h on each subsequent treatment day. A circadian phase assessment was conducted before and after the series of light treatment days to determine the time of the DLMO and DLMOff. Phase delays in the blue-enriched and white conditions were not significantly different (DLMO: -4.45+/-2.02 versus -4.48+/-1.97 h; DLMOff: -3.90+/-1.97 versus -4.35+/-2.39 h, respectively). These results indicate that at light levels commonly used for circadian phase shifting, blue-enriched polychromatic light is no more effective than the white polychromatic lamps of a lower correlated color temperature (CCT) for phase delaying the circadian clock.
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Affiliation(s)
- Mark R Smith
- Rush University Medical Center, Chicago, Illinois 60612, USA
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Chromatic Pupil Responses. Ophthalmology 2009; 116:1564-73. [DOI: 10.1016/j.ophtha.2009.02.007] [Citation(s) in RCA: 155] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Revised: 02/03/2009] [Accepted: 02/03/2009] [Indexed: 11/21/2022] Open
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Mure LS, Cornut PL, Rieux C, Drouyer E, Denis P, Gronfier C, Cooper HM. Melanopsin bistability: a fly's eye technology in the human retina. PLoS One 2009; 4:e5991. [PMID: 19551136 PMCID: PMC2695781 DOI: 10.1371/journal.pone.0005991] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Accepted: 05/06/2009] [Indexed: 11/18/2022] Open
Abstract
In addition to rods and cones, the human retina contains light-sensitive ganglion cells that express melanopsin, a photopigment with signal transduction mechanisms similar to that of invertebrate rhabdomeric photopigments (IRP). Like fly rhodopsins, melanopsin acts as a dual-state photosensitive flip-flop in which light drives both phototransduction responses and chromophore photoregeneration that bestows independence from the retinoid cycle required by rods and cones to regenerate photoresponsiveness following bleaching by light. To explore the hypothesis that melanopsin in humans expresses the properties of a bistable photopigment in vivo we used the pupillary light reflex (PLR) as a tool but with methods designed to study invertebrate photoreceptors. We show that the pupil only attains a fully stabilized state of constriction after several minutes of light exposure, a feature that is consistent with typical IRP photoequilibrium spectra. We further demonstrate that previous exposure to long wavelength light increases, while short wavelength light decreases the amplitude of pupil constriction, a fundamental property of IRP difference spectra. Modelling these responses to invertebrate photopigment templates yields two putative spectra for the underlying R and M photopigment states with peaks at 481 nm and 587 nm respectively. Furthermore, this bistable mechanism may confer a novel form of "photic memory" since information of prior light conditions is retained and shapes subsequent responses to light. These results suggest that the human retina exploits fly-like photoreceptive mechanisms that are potentially important for the modulation of non-visual responses to light and highlights the ubiquitous nature of photoswitchable photosensors across living organisms.
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Affiliation(s)
- Ludovic S. Mure
- Department of Chronobiology, INSERM, U846, Stem Cell and Brain Research Institute, Bron, France
- University of Lyon, Lyon I, UMR-S 846, Lyon, France
| | - Pierre-Loic Cornut
- Department of Chronobiology, INSERM, U846, Stem Cell and Brain Research Institute, Bron, France
- University of Lyon, Lyon I, UMR-S 846, Lyon, France
- Department of Ophthalmology, CHU de Lyon Hopital Edouard Herriot, Lyon, France
| | - Camille Rieux
- Department of Chronobiology, INSERM, U846, Stem Cell and Brain Research Institute, Bron, France
- University of Lyon, Lyon I, UMR-S 846, Lyon, France
| | - Elise Drouyer
- Department of Chronobiology, INSERM, U846, Stem Cell and Brain Research Institute, Bron, France
- University of Lyon, Lyon I, UMR-S 846, Lyon, France
| | - Philippe Denis
- Department of Chronobiology, INSERM, U846, Stem Cell and Brain Research Institute, Bron, France
- University of Lyon, Lyon I, UMR-S 846, Lyon, France
- Department of Ophthalmology, CHU de Lyon Hopital Edouard Herriot, Lyon, France
| | - Claude Gronfier
- Department of Chronobiology, INSERM, U846, Stem Cell and Brain Research Institute, Bron, France
- University of Lyon, Lyon I, UMR-S 846, Lyon, France
| | - Howard M. Cooper
- Department of Chronobiology, INSERM, U846, Stem Cell and Brain Research Institute, Bron, France
- University of Lyon, Lyon I, UMR-S 846, Lyon, France
- * E-mail:
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Pupil constriction evoked in vitro by stimulation of the oculomotor nerve in the turtle (Trachemys scripta elegans). Vis Neurosci 2009; 26:309-18. [PMID: 19523265 DOI: 10.1017/s0952523809090099] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The pond turtle (Trachemys scripta elegans) exhibits a notably sluggish pupillary light reflex (PLR), with pupil constriction developing over several minutes following light onset. In the present study, we examined the dynamics of the efferent branch of the reflex in vitro using preparations consisting of either the isolated head or the enucleated eye. Stimulation of the oculomotor nerve (nIII) using 100-Hz current trains resulted in a maximal pupil constriction of 17.4% compared to 27.1% observed in the intact animal in response to light. When current amplitude was systematically increased from 1 to 400 microA, mean response latency decreased from 64 to 45 ms, but this change was not statistically significant. Hill equations fitted to these responses indicated a current threshold of 3.8 microA. Stimulation using single pulses evoked a smaller constriction (3.8%) with response latencies and threshold similar to that obtained using train stimulation. The response evoked by postganglionic stimulation of the ciliary nerve using 100-Hz trains was largely indistinguishable from that of train stimulation of nIII. However, application of single-pulse stimulation postganglionically resulted in smaller pupil constriction at all current levels relative to that of nIII stimulation, suggesting that there is amplification of efferent drive at the ganglion. Time constants for constrictions ranged from 88 to 154 ms with relaxations occurring more slowly at 174-361 ms. These values for timing from in vitro are much faster than the time constant 1.66 min obtained for the light response in the intact animal. The rapid dynamics of pupil constriction observed here suggest that the slow PLR of the turtle observed in vivo is not due to limitations of the efferent pathway. Rather, the sluggish response probably results from photoreceptive mechanisms or central processing.
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