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Andrabi M, Upton BA, Lang RA, Vemaraju S. An Expanding Role for Nonvisual Opsins in Extraocular Light Sensing Physiology. Annu Rev Vis Sci 2023; 9:245-267. [PMID: 37196422 DOI: 10.1146/annurev-vision-100820-094018] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
We live on a planet that is bathed in daily and seasonal sunlight cycles. In this context, terrestrial life forms have evolved mechanisms that directly harness light energy (plants) or decode light information for adaptive advantage. In animals, the main light sensors are a family of G protein-coupled receptors called opsins. Opsin function is best described for the visual sense. However, most animals also use opsins for extraocular light sensing for seasonal behavior and camouflage. While it has long been believed that mammals do not have an extraocular light sensing capacity, recent evidence suggests otherwise. Notably, encephalopsin (OPN3) and neuropsin (OPN5) are both known to mediate extraocular light sensing in mice. Examples of this mediation include photoentrainment of circadian clocks in skin (by OPN5) and acute light-dependent regulation of metabolic pathways (by OPN3 and OPN5). This review summarizes current findings in the expanding field of extraocular photoreception and their relevance for human physiology.
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Affiliation(s)
- Mutahar Andrabi
- The Visual Systems Group, Abrahamson Pediatric Eye Institute, Division of Pediatric Ophthalmology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA; ,
- Science of Light Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Brian A Upton
- The Visual Systems Group, Abrahamson Pediatric Eye Institute, Division of Pediatric Ophthalmology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA; ,
- Science of Light Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Molecular and Developmental Biology Graduate Program, College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA
- Medical Scientist Training Program, College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA
| | - Richard A Lang
- The Visual Systems Group, Abrahamson Pediatric Eye Institute, Division of Pediatric Ophthalmology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA; ,
- Science of Light Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Ophthalmology, College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA
| | - Shruti Vemaraju
- The Visual Systems Group, Abrahamson Pediatric Eye Institute, Division of Pediatric Ophthalmology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA; ,
- Science of Light Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
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A Transmissive Theory of Brain Function: Implications for Health, Disease, and Consciousness. NEUROSCI 2022. [DOI: 10.3390/neurosci3030032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Identifying a complete, accurate model of brain function would allow neuroscientists and clinicians to make powerful neuropsychological predictions and diagnoses as well as develop more effective treatments to mitigate or reverse neuropathology. The productive model of brain function, which has been dominant in the field for centuries, cannot easily accommodate some higher-order neural processes associated with consciousness and other neuropsychological phenomena. However, in recent years, it has become increasingly evident that the brain is highly receptive to and readily emits electromagnetic (EM) fields and light. Indeed, brain tissues can generate endogenous, complex EM fields and ultraweak photon emissions (UPEs) within the visible and near-visible EM spectra. EM-based neural mechanisms, such as ephaptic coupling and non-visual optical brain signaling, expand canonical neural signaling modalities and are beginning to disrupt conventional models of brain function. Here, we present an evidence-based argument for the existence of brain processes that are caused by the transmission of extracerebral, EM signals and recommend experimental strategies with which to test the hypothesis. We argue for a synthesis of productive and transmissive models of brain function and discuss implications for the study of consciousness, brain health, and disease.
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Zangari A, Micheli D, Galeazzi R, Tozzi A, Balzano V, Bellavia G, Caristo ME. Photons detected in the active nerve by photographic technique. Sci Rep 2021; 11:3022. [PMID: 33542392 PMCID: PMC7862265 DOI: 10.1038/s41598-021-82622-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 01/08/2021] [Indexed: 01/30/2023] Open
Abstract
The nervous system is one of the most complex expressions of biological evolution. Its high performance mostly relies on the basic principle of the action potential, a sequential activation of local ionic currents along the neural fiber. The implications of this essentially electrical phenomenon subsequently emerged in a more comprehensive electromagnetic perspective of neurotransmission. Several studies focused on the possible role of photons in neural communication and provided evidence of the transfer of photons through myelinated axons. A hypothesis is that myelin sheath would behave as an optical waveguide, although the source of photons is controversial. In a previous work, we proposed a model describing how photons would arise at the node of Ranvier. In this study we experimentally detected photons in the node of Ranvier by Ag+ photoreduction measurement technique, during electrically induced nerve activity. Our results suggest that in association to the action potential a photonic radiation takes place in the node.
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Affiliation(s)
- Andrea Zangari
- Pediatric Surgery and Urology Unit, Azienda Ospedaliera San Camillo Forlanini, Circonvallazione Gianicolense 87, 00152, Rome, Italy
| | - Davide Micheli
- Wireless Access Engineering Department, TIM S.P.A., Via Oriolo Romano, 240, 00189, Rome, Italy
| | - Roberta Galeazzi
- Departement of Life and Environmental Science, Università Politecnica delle Marche, via Brecce Bianche, 60131, Ancona, Italy.
| | - Antonio Tozzi
- UOC Fisica Sanitaria, Azienda USL Toscana Sud Est, via Senese 161, 58100, Grosseto, Italy
| | - Vittoria Balzano
- UOC Anatomy and Pathological Histology, Azienda Ospedaliera San Camillo Forlanini, Circonvallazione Gianicolense 87, 00152, Rome, Italy
| | | | - Maria Emiliana Caristo
- Centro Ricerche Sperimentali, Università Cattolica del Sacro Cuore, Largo Agostino Gemelli, 1, 00168, Rome, Italy
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Williams B, Clarke R, Aspe R, Cole M, Hughes J. Managing Performance Throughout Periods of Travel. Strength Cond J 2017. [DOI: 10.1519/ssc.0000000000000317] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Rouleau N, Murugan NJ, Tessaro LWE, Costa JN, Persinger MA. When Is the Brain Dead? Living-Like Electrophysiological Responses and Photon Emissions from Applications of Neurotransmitters in Fixed Post-Mortem Human Brains. PLoS One 2016; 11:e0167231. [PMID: 27907050 PMCID: PMC5131983 DOI: 10.1371/journal.pone.0167231] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Accepted: 11/10/2016] [Indexed: 11/18/2022] Open
Abstract
The structure of the post-mortem human brain can be preserved by immersing the organ within a fixative solution. Once the brain is perfused, cellular and histological features are maintained over extended periods of time. However, functions of the human brain are not assumed to be preserved beyond death and subsequent chemical fixation. Here we present a series of experiments which, together, refute this assumption. Instead, we suggest that chemical preservation of brain structure results in some retained functional capacity. Patterns similar to the living condition were elicited by chemical and electrical probes within coronal and sagittal sections of human temporal lobe structures that had been maintained in ethanol-formalin-acetic acid. This was inferred by a reliable modulation of frequency-dependent microvolt fluctuations. These weak microvolt fluctuations were enhanced by receptor-specific agonists and their precursors (i.e., nicotine, 5-HTP, and L-glutamic acid) as well as attenuated by receptor-antagonists (i.e., ketamine). Surface injections of 10 nM nicotine enhanced theta power within the right parahippocampal gyrus without any effect upon the ipsilateral hippocampus. Glutamate-induced high-frequency power densities within the left parahippocampal gyrus were correlated with increased photon counts over the surface of the tissue. Heschl’s gyrus, a transverse convexity on which the primary auditory cortex is tonotopically represented, retained frequency-discrimination capacities in response to sweeps of weak (2μV) square-wave electrical pulses between 20 Hz and 20 kHz. Together, these results suggest that portions of the post-mortem human brain may retain latent capacities to respond with potential life-like and virtual properties.
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Affiliation(s)
- Nicolas Rouleau
- Biomolecular Sciences Program, Laurentian University, Sudbury, Ontario, Canada
- Behavioural Neuroscience Program, Laurentian University, Sudbury, Ontario, Canada
| | - Nirosha J. Murugan
- Biomolecular Sciences Program, Laurentian University, Sudbury, Ontario, Canada
- Behavioural Neuroscience Program, Laurentian University, Sudbury, Ontario, Canada
| | - Lucas W. E. Tessaro
- Behavioural Neuroscience Program, Laurentian University, Sudbury, Ontario, Canada
- Human Studies Program, Laurentian University, Sudbury, Ontario, Canada
| | - Justin N. Costa
- Behavioural Neuroscience Program, Laurentian University, Sudbury, Ontario, Canada
- Department of Biology, Laurentian University, Sudbury, Ontario, Canada
| | - Michael A. Persinger
- Biomolecular Sciences Program, Laurentian University, Sudbury, Ontario, Canada
- Behavioural Neuroscience Program, Laurentian University, Sudbury, Ontario, Canada
- Human Studies Program, Laurentian University, Sudbury, Ontario, Canada
- Department of Biology, Laurentian University, Sudbury, Ontario, Canada
- * E-mail:
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Nissilä JS, Mänttäri SK, Särkioja TT, Tuominen HJ, Takala TE, Kiviniemi VJ, Sormunen RT, Saarela SYO, Timonen MJ. The distribution of melanopsin (OPN4) protein in the human brain. Chronobiol Int 2016; 34:37-44. [PMID: 27690288 DOI: 10.1080/07420528.2016.1232269] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Until now, melanopsin (OPN4) - a specialized photopigment being responsive especially to blue light wavelengths - has not been found in the human brain at protein level outside the retina. More specifically, OPN4 has only been found in about 2% of retinal ganglion cells (i.e. in intrinsically photosensitive retinal ganglion cells), and in a subtype of retinal cone-cells. Given that Allen Institute for Brain Science has described a wide distribution of OPN4 mRNA in two human brains, we aimed to investigate whether OPN4 is present in the human brain also at protein level. Western blotting and immunohistochemistry, as well as immunoelectron microscopy, were used to analyse the existence and distribution of OPN4 protein in 18 investigated areas of the human brain in samples obtained in forensic autopsies from 10 male subjects (54 ± 3.5 years). OPN4 protein expression was found in all subjects, and, furthermore, in 5 out of 10 subjects in all investigated brain areas localized in membranous compartments and cytoplasmic vesicles of neurons. To our opinion, the wide distribution of OPN4 in central areas of the human brain evokes a question whether ambient light has important straight targets in the human brain outside the retinohypothalamic tract (RHT). Further studies are, however, needed to investigate the putative physiological phototransductive actions of inborn OPN4 protein outside the RHT in the human brain.
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Affiliation(s)
- Juuso S Nissilä
- a University of Oulu, Center for Life Course Health Research , Oulu , Finland.,b Department of Biology, University of Oulu , Oulu , Finland
| | - Satu K Mänttäri
- b Department of Biology, University of Oulu , Oulu , Finland
| | - Terttu T Särkioja
- c University of Oulu , Institute of Diagnostics, Forensic Medicine , Oulu , Finland
| | - Hannu J Tuominen
- d University of Oulu , Institute of Diagnostics, Pathology , Oulu , Finland.,e Department of Pathology , Oulu University Hospital , Oulu , Finland
| | | | - Vesa J Kiviniemi
- g Department of Diagnostic Radiology , Oulu University Hospital , Oulu , Finland
| | - Raija T Sormunen
- d University of Oulu , Institute of Diagnostics, Pathology , Oulu , Finland.,e Department of Pathology , Oulu University Hospital , Oulu , Finland.,h Biocenter Oulu , University of Oulu , Oulu , Finland
| | | | - Markku J Timonen
- a University of Oulu, Center for Life Course Health Research , Oulu , Finland
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Karbowski LM, Saroka KS, Murugan NJ, Persinger MA. LORETA indicates frequency-specific suppressions of current sources within the cerebrums of blindfolded subjects from patterns of blue light flashes applied over the skull. Epilepsy Behav 2015; 51:127-32. [PMID: 26276250 DOI: 10.1016/j.yebeh.2015.06.039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 05/27/2015] [Accepted: 06/20/2015] [Indexed: 10/23/2022]
Abstract
An array of eight cloistered (completely covered) 470-nm LEDs was attached to the right caudal scalp of subjects while each sat blindfolded within a darkened chamber. The LEDs were activated by a computer-generated complex (frequency-modulated) temporal pattern that, when applied as weak magnetic fields, has elicited sensed presences and changes in LORETA (low-resolution electromagnetic tomography) configurations. Serial 5-min on to 5-min off presentations of the blue light (10,000lx) resulted in suppression of gamma activity within the right cuneus (including the extrastriate area), beta activity within the left angular and right superior temporal regions, and alpha power within the right parahippocampal region. The effect required about 5min to emerge followed by a transient asymptote for about 15 to 20min when diminished current source density was evident even during no light conditions. Subjective experiences, as measured by our standard exit questionnaire, reflected sensations similar to those reported when the pattern was presented as a weak magnetic field. Given previous evidence that photon flux density of this magnitude can penetrate the skull, these results suggest that properly configured LEDs that generate physiologically patterned light sequences might be employed as noninvasive methods to explore the dynamic characteristics of cerebral activity in epileptic and nonepileptic brains.
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Affiliation(s)
- Lukasz M Karbowski
- Behavioural Neuroscience Program, Laurentian University, Sudbury, Ontario P3E 2C6, Canada; Biomolecular Sciences Program, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - Kevin S Saroka
- Behavioural Neuroscience Program, Laurentian University, Sudbury, Ontario P3E 2C6, Canada; Human Studies Program, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - Nirosha J Murugan
- Behavioural Neuroscience Program, Laurentian University, Sudbury, Ontario P3E 2C6, Canada; Biomolecular Sciences Program, Laurentian University, Sudbury, Ontario P3E 2C6, Canada
| | - Michael A Persinger
- Behavioural Neuroscience Program, Laurentian University, Sudbury, Ontario P3E 2C6, Canada; Human Studies Program, Laurentian University, Sudbury, Ontario P3E 2C6, Canada; Biomolecular Sciences Program, Laurentian University, Sudbury, Ontario P3E 2C6, Canada.
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Flyktman A, Mänttäri S, Nissilä J, Timonen M, Saarela S. Transcranial light affects plasma monoamine levels and expression of brain encephalopsin in the mouse. ACTA ACUST UNITED AC 2015; 218:1521-6. [PMID: 25805701 DOI: 10.1242/jeb.111864] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 03/09/2015] [Indexed: 11/20/2022]
Abstract
Encephalopsin (OPN3) belongs to the light-sensitive transmembrane receptor family mainly expressed in the brain and retina. It is believed that light affects mammalian circadian rhythmicity only through the retinohypothalamic tract, which transmits light information to the suprachiasmatic nucleus in the hypothalamus. However, it has been shown that light penetrates the skull. Here, we present the effect of transcranial light treatment on OPN3 expression and monoamine concentrations in mouse brain and other tissues. Mice were randomly assigned to control group, morning-light group and evening-light group, and animals were illuminated transcranially five times a week for 8 min for a total of 4 weeks. The concentrations of OPN3 and monoamines were analysed using western blotting and HPLC, respectively. We report that transcranial light treatment affects OPN3 expression in different brain areas and plasma/adrenal gland monoamine concentrations. In addition, when light was administered at a different time of the day, the response varied in different tissues. These results provide new information on the effects of light on transmitters mediating mammalian rhythmicity.
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Affiliation(s)
- Antti Flyktman
- University of Oulu, Department of Biology, P.O. Box 3000, Oulu FIN-90014, Finland
| | - Satu Mänttäri
- Finnish Institute of Occupational Health, Aapistie 1, Oulu FI-90220, Finland
| | - Juuso Nissilä
- University of Oulu, Department of Biology, P.O. Box 3000, Oulu FIN-90014, Finland University of Oulu, Institute of Health Sciences, P.O. Box 5000, Oulu FIN-90014, Finland
| | - Markku Timonen
- University of Oulu, Institute of Health Sciences, P.O. Box 5000, Oulu FIN-90014, Finland
| | - Seppo Saarela
- University of Oulu, Department of Biology, P.O. Box 3000, Oulu FIN-90014, Finland
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Jurvelin H, Takala T, Nissilä J, Timonen M, Rüger M, Jokelainen J, Räsänen P. Transcranial bright light treatment via the ear canals in seasonal affective disorder: a randomized, double-blind dose-response study. BMC Psychiatry 2014; 14:288. [PMID: 25330838 PMCID: PMC4207317 DOI: 10.1186/s12888-014-0288-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 10/03/2014] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Bright light treatment is effective for seasonal affective disorder (SAD), although the mechanisms of action are still unknown. We investigated whether transcranial bright light via the ear canals has an antidepressant effect in the treatment of SAD. METHODS During the four-week study period, 89 patients (67 females; 22 males, aged 22-65, mean ± SD age: 43.2 ± 10.9 years) suffering from SAD were randomized to receive a 12-min daily dose of photic energy of one of three intensities (1 lumen/0.72 mW/cm(2); 4 lumens/2.881 mW/cm(2); 9 lumens/6.482 mW/cm(2)) via the ear canals. The light was produced using light-emitting diodes. The severity of depressive symptoms was assessed with the Hamilton Depression Rating Scale - Seasonal Affective Disorder (SIGH-SAD), the Hamilton Anxiety Rating Scale (HAMA), and the Beck Depression Inventory (BDI). Cognitive performance was measured by the Trail Making Test (TMT). The within-group and between-group changes in these variables throughout the study were analysed with a repeated measures analysis of variance (ANOVA), whereas gender differences at baseline within the light groups were analysed using Student's t-tests. RESULTS Patients in all three groups showed significant decreases in their BDI, HAMA, and SIGH-SAD scores. Response rates, i.e., an at least 50% decrease of symptoms as measured by the BDI, were 74%-79% in the three treatment groups. Corresponding variations for the SIGH-SAD and the HAMA were 35-45% and 47-62%, respectively. No intensity-based dose-response relationships in the improvement of anxiety and depressive symptoms or cognitive performance between treatment groups were observed. Approximately one in four patients experienced mild adverse effects, of which the most common were headache, insomnia, and nausea. CONCLUSIONS These results suggests that transcranial bright light treatment may have antidepressant and anxiolytic effect in SAD patients, as both self- and psychiatrist-rated depressive and anxiety symptoms decreased in all treatment groups. These improvements are comparable to findings of earlier bright light studies that used conventional devices. The lack of dose response may be due to a saturation effect above a certain light intensity threshold. Further studies on the effects of transcranial bright light with an adequate placebo condition are needed. TRIAL REGISTRATION NCT01293409, ClinicalTrials.gov.
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Affiliation(s)
- Heidi Jurvelin
- />Department of Psychiatry, University of Oulu, Institute of Clinical Medicine, Box 5000, 90014 Oulu, Finland
- />University of Oulu, Institute of Health Sciences, Box 5000, 90014 Oulu, Finland
- />Valkee Oy, Elektroniikkatie 4, 90590 Oulu, Finland
| | - Timo Takala
- />Oulu Deaconess Institute, Box 365, 90101 Oulu, Finland
| | - Juuso Nissilä
- />University of Oulu, Institute of Health Sciences, Box 5000, 90014 Oulu, Finland
- />Valkee Oy, Elektroniikkatie 4, 90590 Oulu, Finland
| | - Markku Timonen
- />University of Oulu, Institute of Health Sciences, Box 5000, 90014 Oulu, Finland
- />Oulu Health Center, Box 8, 90015 Oulu, Finland
| | - Melanie Rüger
- />Valkee Oy, Elektroniikkatie 4, 90590 Oulu, Finland
| | - Jari Jokelainen
- />University of Oulu, Institute of Health Sciences, Box 5000, 90014 Oulu, Finland
- />Unit of General Practice, Oulu University Hospital, 90029 Oulu, Finland
| | - Pirkko Räsänen
- />Department of Psychiatry, University of Oulu, Institute of Clinical Medicine, Box 5000, 90014 Oulu, Finland
- />Department of Psychiatry, Oulu University Hospital, Box 26, 90026 Oulu, Finland
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Jurvelin H, Takala T, Heberg L, Nissilä J, Rüger M, Leppäluoto J, Saarela S, Vakkuri O. Transcranial bright light exposure via ear canals does not suppress nocturnal melatonin in healthy adults – A single-blind, sham-controlled, crossover trial. Chronobiol Int 2014; 31:855-60. [DOI: 10.3109/07420528.2014.916297] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Tang R, Dai J. Biophoton signal transmission and processing in the brain. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2013; 139:71-5. [PMID: 24461927 DOI: 10.1016/j.jphotobiol.2013.12.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 12/13/2013] [Accepted: 12/13/2013] [Indexed: 11/19/2022]
Abstract
The transmission and processing of neural information in the nervous system plays a key role in neural functions. It is well accepted that neural communication is mediated by bioelectricity and chemical molecules via the processes called bioelectrical and chemical transmission, respectively. Indeed, the traditional theories seem to give valuable explanations for the basic functions of the nervous system, but difficult to construct general accepted concepts or principles to provide reasonable explanations of higher brain functions and mental activities, such as perception, learning and memory, emotion and consciousness. Therefore, many unanswered questions and debates over the neural encoding and mechanisms of neuronal networks remain. Cell to cell communication by biophotons, also called ultra-weak photon emissions, has been demonstrated in several plants, bacteria and certain animal cells. Recently, both experimental evidence and theoretical speculation have suggested that biophotons may play a potential role in neural signal transmission and processing, contributing to the understanding of the high functions of nervous system. In this paper, we review the relevant experimental findings and discuss the possible underlying mechanisms of biophoton signal transmission and processing in the nervous system.
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Affiliation(s)
- Rendong Tang
- Wuhan Institute for Neuroscience and Neuroengineering, South-Central University for Nationalities, Wuhan 430074, China
| | - Jiapei Dai
- Wuhan Institute for Neuroscience and Neuroengineering, South-Central University for Nationalities, Wuhan 430074, China.
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