Article
Multidisciplinary Sciences
Robin A. Schoonderwoerd, Mischa de Rover, Jan A. M. Janse, Lydiane Hirschler, Channa R. Willemse, Leonie Scholten, Ilse Klop, Sander van Berloo, Matthias J. P. van Osch, Dick F. Swaab, Johanna H. Meijer
Summary: In modern society, the widespread use of artificial light at night disrupts our central circadian clock, the suprachiasmatic nucleus (SCN), by suppressing blood oxygen level-dependent (BOLD) functional MRI signals in the SCN. Contrary to expectations, not only blue light, but also green and orange light, can cause this suppression, while violet light does not. This suggests that strategies for light exposure need revision, with the possibility of using wavelengths other than blue to enhance light levels during the daytime and potential disruption from all colors during the nighttime.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Neurosciences
Hugo Calligaro, Azarin Shoghi, Xinyue Chen, Keun-Young Kim, Hsin Liu Yu, Brian Khov, Benjamin Finander, Hiep Le, Mark H. Ellisman, Satchidananda Panda
Summary: The hypothalamic suprachiasmatic nucleus (SCN) is the central circadian pacemaker in vertebrates that receives photic information to synchronize circadian rhythms. Two major types of peptidergic neurons in the core and shell regions of SCN and their interaction with melanopsin-expressing retinal ganglion cells (mRGCs) are essential to understanding light regulation of the circadian clock and local circuits within the SCN.
Review
Neurosciences
Nikolas Bergum, Casey-Tyler Berezin, Jozsef Vigh
Summary: Chronic opioid use is associated with sleep disturbances, but the mechanism is unclear. Animal studies suggest that opioids disrupt the circadian rhythms by affecting retinal cells responsible for light detection. Therefore, ipRGCs may be a potential therapeutic target for opioid-related sleep problems.
FRONTIERS IN NEUROSCIENCE
(2022)
Article
Chemistry, Analytical
Sam B. Choi, Tarlan Vatan, Theresa A. Alexander, Chenghang Zhang, Shyrice M. Mitchell, Colenso M. Speer, Peter Nemes
Summary: During brain development, the formation of axonal projections in the mouse visual system is influenced by both spontaneous retinal activity and visual experience. However, the precise proteomic changes in the retinorecipient targets during this developmental transition are still unknown.
ANALYTICAL CHEMISTRY
(2023)
Review
Biology
Ely Contreras, Alexis P. Nobleman, Phyllis R. Robinson, Tiffany M. Schmidt
Summary: Melanopsin is a visual pigment expressed in a small subset of intrinsically photosensitive retinal ganglion cells, regulating both non-image forming and image-forming visual functions. Recent research has identified multiple subtypes of ipRGCs with unique properties, challenging the traditional view of melanopsin phototransduction as a single pathway.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2021)
Article
Endocrinology & Metabolism
Josh W. Mouland, Franck P. Martial, Robert J. Lucas, Timothy M. Brown
Summary: This study found that changes in melanopsin irradiance largely account for the light-induced changes in SCN activity in naturalistic spatiotemporal variations, while cone signals only influenced SCN activity when spatiotemporal contrast was low. These results emphasize the importance of modulating effective irradiance for melanopsin in controlling the circadian impact of light.
JOURNAL OF PINEAL RESEARCH
(2021)
Article
Cell Biology
Fang Gao, Jun Ma, Yao-Qing Yu, Xiao-Fei Gao, Yang Bai, Yi Sun, Juan Liu, Xianyu Liu, Devin M. Barry, Steven Wilhelm, Tyler Piccinni-Ash, Na Wang, Dongyang Liu, Rachel A. Ross, Yan Hao, Xu Huang, Jin-Jing Jia, Qianyi Yang, Hao Zheng, Johan van Nispen, Jun Chen, Hui Li, Jiayi Zhang, Yun-Qing Li, Zhou-Feng Chen
Summary: This study reveals that visual itch information is transmitted from the retina to GRP neurons through ipRGCs and GRPR neurons in the SCN mediate contagious itch behavior. The PVT is involved in relaying itch information. These findings suggest the existence of a previously unknown visual pathway that encodes salient environmental cues and enables animals to imitate behaviors of conspecifics to cope with adverse conditions.
Article
Neurosciences
Michael D. Flood, Hannah L. B. Veloz, Samer Hattar, Joao L. Carvalho-de-Souza
Summary: Intrinsically photosensitive retinal ganglion cells (ipRGCs) express melanopsin and can respond to light independently of rod and cone photoreceptors. They play important roles in non-image-forming aspects of vision and directly contribute to pattern-forming vision. The study shows that melanopsin-mediated phototransduction can significantly contribute to the primary pattern-forming visual pathway.
FRONTIERS IN CELLULAR NEUROSCIENCE
(2022)
Article
Multidisciplinary Sciences
Babak Zandi, Tran Quoc Khanh
Summary: Research has made significant findings in the neurophysiological process behind the pupillary light reflex, but temporal prediction of the pupil diameter triggered by polychromatic or chromatic stimulus spectra remains challenging. Current state-of-the-art pupil models do not map the temporal receptor-weighting or spectral-dependent adaptation behavior of the afferent pupil control path. A new deep learning-driven concept of a pupil model has been proposed to predict the temporal pupil light response accurately.
SCIENTIFIC REPORTS
(2021)
Review
Biochemistry & Molecular Biology
Marcos L. Aranda, Tiffany M. Schmidt
Summary: The discovery of ipRGCs has shed light on their diverse roles in various visual functions and behaviors, such as regulating circadian rhythms, driving pupillary light reflex, and modulating mood and alertness. The presence of melanopsin as a unique molecular signature has enabled the development of molecular and genetic tools for studying ipRGC circuits.
CELLULAR AND MOLECULAR LIFE SCIENCES
(2021)
Article
Multidisciplinary Sciences
Ethan O. Contreras, Carley G. Dearing, Crystal A. Ashinhurst, Betty A. Fish, Sajila N. Hossain, Ariana M. Rey, Primal D. Silva, Stewart Thompson
Summary: The study found that in different disease models of retinal degeneration, two responses to light could be affected in opposite ways, and changes in a specific response to light did not accurately represent the degree of pathology.
Article
Multidisciplinary Sciences
Lujing Chen, Guang Li, Zheng Jiang, King-Wai Yau
Summary: Nonimage-forming vision in mammals is mediated primarily by melanopsin-expressing ipRGCs. The study reveals that in M1-ipRGCs, melanopsin activates phospholipase C-β4 to open TRPC6 and TRPC7 channels, while in M2 and M4-ipRGCs, cyclic nucleotide-mediated phototransduction activates hyperpolarization and cyclic nucleotide-gated channels. Additionally, it is found that the upstream G protein is Gq, which directly activates adenylyl cyclase (AC) for signaling.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Agriculture, Dairy & Animal Science
Brooke Van Wyk, Gregory Fraley
Summary: Birds perceive light differently than mammals, with deep brain photoreceptors playing a role in seasonal fertility. A study found that birds express high levels of photoreceptor OPN4 on the day of hatching, suggesting additional functions beyond reproduction. The ontogeny of deep brain photoreceptors was analyzed, showing that ducks exhibit adult-like OPN4 gene expression on Day 0, with peak expression levels at week 19 coinciding with peak fertility.
Article
Neurosciences
Shane P. D'Souza, David Swygart, Sophia R. Wienbar, Brian A. Upton, Kevin X. Zhang, Robert D. Mackin, Anna K. Casasent, Melanie A. Samuel, Gregory W. Schwartz, Richard A. Lang
Summary: Understanding the parts list of sensory components in the retina is crucial for studying the effects of light on behavior, health, and disease. This study reveals the expression patterns of Opn5 in retinal ganglion cells, which are nonhomogenously distributed in the retina with higher densities in the dorsotemporal quadrant. Through molecular and electrophysiological profiling, it is discovered that Opn5-RGCs comprise previously defined RGC types that respond optimally to edges and object motion, expanding the roles of image-forming cells in retinal physiology and function.
JOURNAL OF COMPARATIVE NEUROLOGY
(2022)
Article
Multidisciplinary Sciences
R. C. Feord, A. Gomoliszewska, A. Pienaar, J. W. Mouland, T. M. Brown
Summary: This study establishes a new method for studying cone function in mice and reveals the widespread presence of cone-opponent processing in the mouse visual system. This research provides new insights into the functional characteristics of color processing pathways in mice.
SCIENTIFIC REPORTS
(2023)
Article
Biology
Annette E. Allen, Josh W. Mouland, Jessica Rodgers, Beatriz Bano-Otalora, Ronald H. Douglas, Glen Jeffery, Anthony A. Vugler, Timothy M. Brown, Robert J. Lucas
JOURNAL OF EXPERIMENTAL BIOLOGY
(2020)
Article
Endocrinology & Metabolism
Timothy M. Brown
JOURNAL OF PINEAL RESEARCH
(2020)
Article
Multidisciplinary Sciences
Sarika Paul, Lydia Hanna, Court Harding, Edward A. Hayter, Lauren Walmsley, David A. Bechtold, Timothy M. Brown
NATURE COMMUNICATIONS
(2020)
Article
Environmental Sciences
Ellen E. Lee, Ameya Amritwar, L. Elliot Hong, Iqra Mohyuddin, Timothy Brown, Teodor T. Postolache
INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH
(2020)
Article
Neurosciences
Patrycja Orlowska-Feuer, Annette Elisabeth Allen, Timothy Matthew Brown, Hanna Jowita Szkudlarek, Robert James Lucas, Riccardo Storchi
Summary: Neurophysiological activity in the subcortical visual system shows fluctuations in infra-slow and fast oscillatory ranges, with the phase of infra-slow modulating fast beta/gamma oscillations. Genetic ablations reveal that infra-slow and fast oscillations interact uniquely, potentially guiding visual processing. This interaction may play a significant role in vision function and disruptions in these oscillatory behaviors could contribute to vision dysfunction in retinal dystrophy.
JOURNAL OF PHYSIOLOGY-LONDON
(2021)
Editorial Material
Neurosciences
Nina Milosavljevic, Timothy M. Brown, Robert J. Lucas
Summary: In this issue of Neuron, Huang et al. (2021) demonstrate a new influence of light on memory, showing that prolonged exposure to bright light can enhance spatial memory in mice. They attribute this effect to a neural circuit involving the retina, ventral lateral geniculate, and reuniens nuclei.
Article
Biochemistry & Molecular Biology
Jessica Rodgers, Beatriz Bano-Otalora, Mino D. C. Belle, Sarika Paul, Rebecca Hughes, Phillip Wright, Richard McDowell, Nina Milosavljevic, Patrycja Orlowska-Feuer, Franck P. Martial, Jonathan Wynne, Edward R. Ballister, Riccardo Storchi, Annette E. Allen, Timothy Brown, Robert J. Lucas
Summary: There is no consensus on the best inhibitory optogenetic tool. Gi/o signalling is a native mechanism of neuronal inhibition, and Lamprey Parapinopsin (Lamplight) can be used for optogenetic silencing by switching between stable signalling active and inactive states with different wavelengths. The properties of Lamplight can be applied to achieve switchable neuronal hyperpolarisation and suppression of spontaneous spike firing in specific brain regions. Expressing Lamplight in ON bipolar cells can photosensitise retinas following advanced photoreceptor degeneration, showing potential for scalable, sustained, and reversible optogenetic inhibition.
Article
Endocrinology & Metabolism
Timothy M. Brown, Kavita Thapan, Josephine Arendt, Victoria L. Revell, Debra J. Skene
Summary: The influence of light on human physiology and behavior is well-established, with studies showing that both melanopsin and S-cones play a role in the suppression of melatonin. Data suggests an initial contribution of S-cones to melatonin suppression that diminishes under extended light exposure.
JOURNAL OF PINEAL RESEARCH
(2021)
Article
Endocrinology & Metabolism
Josh W. Mouland, Franck P. Martial, Robert J. Lucas, Timothy M. Brown
Summary: This study found that changes in melanopsin irradiance largely account for the light-induced changes in SCN activity in naturalistic spatiotemporal variations, while cone signals only influenced SCN activity when spatiotemporal contrast was low. These results emphasize the importance of modulating effective irradiance for melanopsin in controlling the circadian impact of light.
JOURNAL OF PINEAL RESEARCH
(2021)
Article
Multidisciplinary Sciences
Edward A. Hayter, Sophie M. T. Wehrens, Hans P. A. Van Dongen, Alessandra Stangherlin, Shobhan Gaddameedhi, Elena Crooks, Nichola J. Barron, Luigi A. Venetucci, John S. O' Neill, Timothy M. Brown, Debra J. Skene, Andrew W. Trafford, David A. Bechtold
Summary: The electrical activity of the heart is regulated by circadian clocks in the brain and heart, leading to time-dependent susceptibility to arrhythmias. Different inputs from the autonomic nervous system and cardiomyocyte clock affect the SA and AV nodes, making the cardiac conduction system sensitive to abrupt changes in behavior and sleep-wake timing.
NATURE COMMUNICATIONS
(2021)
Article
Biochemistry & Molecular Biology
Josh W. Mouland, Abigail Pienaar, Christopher Williams, Alex J. Watson, Robert J. Lucas, Timothy M. Brown
Summary: Color vision, originated from opponent processing of spectrally distinct photoreceptor signals, plays crucial roles in animal behavior, including in laboratory mammals like mice. Recent studies have found that mice demonstrate robust chromatic discrimination in the central-upper visual field, challenging the traditional notion of color vision impediment due to the expression gradient of Sand M-cone opsin in the retina. Moreover, new mechanisms beyond the proposed retinal opponent processes may be involved in supporting extensive and sophisticated color processing in the mouse lateral geniculate nucleus (LGN).
Article
Multidisciplinary Sciences
Beatriz Bano-Otalora, Franck Martial, Court Harding, David A. Bechtold, Annette E. Allen, Timothy M. Brown, Mino D. C. Belle, Robert J. Lucas
Summary: The study reveals an impact of daytime light intensity on SCN physiology and the amplitude of circadian rhythms, with lower daytime irradiance leading to a marked reduction in the amplitude of spontaneous activity.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Biology
Altug Didikoglu, Benjamin Walker, Asri Maharani, Neil Pendleton, Maria Merce Canal, Antony Payton, Jon Gibson, Timothy Brown
Summary: Individuals with an 'evening' chronotype have a higher risk of adverse occupational, educational, and health outcomes in older adults due to their vulnerability to circadian and sleep disruption.
CHRONOBIOLOGY INTERNATIONAL
(2022)
Article
Biochemistry & Molecular Biology
Timothy M. Brown, George C. Brainard, Christian Cajochen, Charles A. Czeisler, John P. Hanifin, Steven W. Lockley, Robert J. Lucas, Mirjam Muench, John B. O'Hagan, Stuart N. Peirson, Luke L. A. Price, Till Roenneberg, Luc J. M. Schlangen, Debra J. Skene, Manuel Spitschan, Celine Vetter, Phyllis C. Zee, Kenneth P. Wright
Summary: Ocular light exposure has significant effects on human health and well-being, affecting circadian rhythms, sleep, neuroendocrine and cognitive functions. Advances in understanding the mechanisms and emerging lighting technologies allow for the adjustment of lighting to promote optimal physical and mental health and performance. A new international standard provides a way to quantify the influence of light on retinal neurons, and this report provides lighting recommendations based on scientific consensus, with a focus on easily measured quantities.
Article
Biology
E. Tamayo, J. W. Mouland, R. J. Lucas, T. M. Brown
Summary: Animal survival depends on the ability to adjust behavior according to environmental conditions, including the perception of light. The circadian system plays a key role in regulating rest and activity based on diel changes in light quantity and spectral content. This study reveals that the acute effects of light on behavior in mice are influenced by both melanopsin-dependent irradiance signals and the spectral content of the light.
