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Estay-Ahumada CE, Verra DM, Roux M, Sassone F, Felder-Schmittbuhl MP, Klopp C, Ciocca D, Moal MLL, Hicks D. Hyperglycemia and circadian disruption lead to retinal dysfunction in a stabilized colony of the fat sand rat Psammomys obesus. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167118. [PMID: 38490291 DOI: 10.1016/j.bbadis.2024.167118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 03/04/2024] [Accepted: 03/05/2024] [Indexed: 03/17/2024]
Abstract
PURPOSE The Fat Sand Rat (Psammomys obesus) recapitulates several features of human pre-proliferative diabetic retinopathy, but data are restricted to wild animals, incompatible with stringent biomedical research criteria. To overcome this barrier, we characterized retinal changes in a colony of P. obsesus maintained under strictly controlled housing conditions. METHODS Animals were maintained on low or high caloric energy diets, and raised under either standard (12 h light/12 h dark) or shortened (5 h light/5 h dark) photoperiods. Visual responses were tested by electroretinography, while structural/molecular changes were assayed by immunochemistry and molecular biology (RNAseq and qPCR). RESULTS Whereas high calorie diet alone did not induce hyperglycemia, coupled with short photoperiod >80 % animals developed severe hyper-insulinemia by 15 weeks, and 16 % animals further developed hyperglycemia. In these groups, electroretinography showed significant declines in visual responses in both hyper-insulinemic and hyperglycemic animals, especially in photopic (cone) responses. Transcriptomics analysis of hyperglycemic compared to low caloric controls revealed major upregulation in pathways involved in glial activation, extracellular matrix remodeling, inflammation, cytokine production, partial ischemic responses and angiogenesis. Western blotting against rhodopsin and cone opsin also showed decreased levels in both groups, overall decreases being greater for cones than rods in hyperglycemic animals. CONCLUSIONS P. obesus maintained in rigorously monitored captive conditions, albeit showing attenuated responses to dietary overload compared to wild counterparts, nevertheless do develop some retinal features of diabetic retinopathy-like degeneration. Such a colony with known sanitary status opens their broader use for biomedical research.
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Affiliation(s)
- Catherine E Estay-Ahumada
- Institut des Neurosciences Cellulaires et Intégratives CNRS UPR 3212, 8 Allée du Général Rouvillois, 67000 Strasbourg, France.
| | - Daniela M Verra
- Institut des Neurosciences Cellulaires et Intégratives CNRS UPR 3212, 8 Allée du Général Rouvillois, 67000 Strasbourg, France
| | - Michel Roux
- IGBMC - CNRS UMR 7104 Inserm U 1258, 1 rue Laurent Fries, BP 10142, 67404 Illkirch CEDEX, France.
| | - Fabiana Sassone
- Institut des Neurosciences Cellulaires et Intégratives CNRS UPR 3212, 8 Allée du Général Rouvillois, 67000 Strasbourg, France.
| | - Marie-Paule Felder-Schmittbuhl
- Institut des Neurosciences Cellulaires et Intégratives CNRS UPR 3212, 8 Allée du Général Rouvillois, 67000 Strasbourg, France.
| | - Christophe Klopp
- Sigenae, Genotoul Bioinfo, BioInfoMics, MIAT UR875, INRAE, Castanet Tolosan, France.
| | - Dominique Ciocca
- Chronobiotron CNRS UMR 3415, 8 Allée Rouvillois, 67000 Strasbourg, France.
| | - Myriam Ly-Le Moal
- Institut Roche, 4 cours de l'île Seguin, 92100 Boulogne-Billancourt, France.
| | - David Hicks
- Institut des Neurosciences Cellulaires et Intégratives CNRS UPR 3212, 8 Allée du Général Rouvillois, 67000 Strasbourg, France.
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Xu G, Luo Y, Qi H, Liu S, Fu J, Ye Z, Li Z. Trichromatic critical flicker frequency as potential visual test in cataract and macula disease patients. Graefes Arch Clin Exp Ophthalmol 2024:10.1007/s00417-024-06398-w. [PMID: 38329529 DOI: 10.1007/s00417-024-06398-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 01/21/2024] [Accepted: 01/30/2024] [Indexed: 02/09/2024] Open
Abstract
PURPOSE To investigate the capacity of critical flicker frequency (CFF) in discriminating cataract eyes with or without macula disease using trichromatic flickers, and to develop a model to predict postoperative best corrected visual acuity (BCVA). METHODS Patients were divided into two groups based on the presence or absence of macular disease. CFF threshold measurements of red (R-CFF), green (G-CFF), and yellow (Y-CFF) flickers were conducted both preoperatively and postoperatively. A generalized estimating equations model (GEE) was employed to examine the relationship between CFF threshold and 3-month postoperative BCVA. RESULTS A total of 115 eyes were enrolled, with 59 eyes in the cataract alone group and 56 eyes in the cataract with macular disease group completing the follow-up. R-CFF was found to be consistent before and after cataract removal (P = 0.06), even in cases where OCT was not performed successfully (P > 0.05). Y-CFF showed the highest AUC (0.798) for differentiating ocular comorbidities. According to the GEE model, in patients with a CFF threshold below 26 Hz, the odds ratios for achieving a postoperative VA of 20/40 or better were 34.8% for R-CFF, 26.0% for G-CFF, and 24.5% for Y-CFF. CONCLUSION CFF emerges as a promising tool for predicting postoperative BCVA, providing valuable supplementary insights when fundus examination is obstructed. R-CFF demonstrates the best resistance to cataracts, while Y-CFF exhibits the highest sensitivity both in identifying macular diseases and predicting postoperative BCVA of 20/40 or better.
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Affiliation(s)
- Guangcan Xu
- School of Medicine, Nankai University, Tianjin, 300071, China
- Department of Ophthalmology, The Third Medical Center, The Chinese PLA General Hospital, Beijing, 100853, China
| | - Yu Luo
- Department of Ophthalmology, The Third Medical Center, The Chinese PLA General Hospital, Beijing, 100853, China
- Medical School of Chinese PLA, Beijing, 100853, China
| | - Haolan Qi
- School of Medicine, Nankai University, Tianjin, 300071, China
- Department of Ophthalmology, The Third Medical Center, The Chinese PLA General Hospital, Beijing, 100853, China
| | - Sijia Liu
- Department of Ophthalmology, The Third Medical Center, The Chinese PLA General Hospital, Beijing, 100853, China
- Medical School of Chinese PLA, Beijing, 100853, China
| | - Junxia Fu
- Department of Ophthalmology, School of Medicine, Xinhua Hospital Affiliated to Shanghai Jiao Tong University, Shanghai, 200092, China
| | - Zi Ye
- Department of Ophthalmology, The Third Medical Center, The Chinese PLA General Hospital, Beijing, 100853, China.
- Medical School of Chinese PLA, Beijing, 100853, China.
| | - Zhaohui Li
- School of Medicine, Nankai University, Tianjin, 300071, China.
- Department of Ophthalmology, The Third Medical Center, The Chinese PLA General Hospital, Beijing, 100853, China.
- Medical School of Chinese PLA, Beijing, 100853, China.
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Xu G, Fu J, Qi H, Li L, Chen W, Gao Y, Ma T, Ye Z, Li Z. The theory of critical flicker fusion frequency and its application in cataracts. ADVANCES IN OPHTHALMOLOGY PRACTICE AND RESEARCH 2023; 3:29-32. [PMID: 37846427 PMCID: PMC10577820 DOI: 10.1016/j.aopr.2022.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 10/05/2022] [Accepted: 10/09/2022] [Indexed: 10/18/2023]
Abstract
Background Due to media opacity, it is usually difficult to accurately evaluate the postoperative visual acuity in cataracts patients. As a small and portable tool, the critical flicker fusion frequency (CFF) device reflects the temporal resolution of visual function and has been widely used in clinical research. However, poor understanding of the technique and equipment limitations have restricted its clinical application in China. Main text There was a decrease in the CFF value in various ophthalmic diseases, indicating that the CFF is sensitive to detect visual functional changes. A number of studies have shown that the CFF test can accurately distinguish patients with simple cataracts from those with cataracts combined with fundus disease, and, as a visual test, it can more accurately predict postoperative visual acuity without being affected by media opacity. This study comprehensive reviews the basic principles of CFF and its application in ophthalmology, especially in cataracts. Conclusions As one of the tools for dynamic visual function detection, the CFF test could help doctors to assess the possible presence of fundus disease in cataracts patients, especially in eyes with dense cataracts, and more precisely provide a reasonable visual prognosis than other available visual tests.
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Affiliation(s)
- Guangcan Xu
- School of Medicine, Nankai University, Tianjin, China
- Department of Ophthalmology, The Third Medical Center, The Chinese People's Liberation Army General Hospital, Beijing, China
| | - Junxia Fu
- Department of Ophthalmology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Haolan Qi
- School of Medicine, Nankai University, Tianjin, China
- Department of Ophthalmology, The Third Medical Center, The Chinese People's Liberation Army General Hospital, Beijing, China
| | - Linyu Li
- School of Medicine, Nankai University, Tianjin, China
- Department of Ophthalmology, The Third Medical Center, The Chinese People's Liberation Army General Hospital, Beijing, China
| | - Wenqian Chen
- Department of Ophthalmology, The Third Medical Center, The Chinese People's Liberation Army General Hospital, Beijing, China
| | - Yi Gao
- Department of Ophthalmology, The Third Medical Center, The Chinese People's Liberation Army General Hospital, Beijing, China
| | - Tianju Ma
- Department of Ophthalmology, The Third Medical Center, The Chinese People's Liberation Army General Hospital, Beijing, China
| | - Zi Ye
- Department of Ophthalmology, The Third Medical Center, The Chinese People's Liberation Army General Hospital, Beijing, China
- The Chinese People's Liberation Army Medical School, Beijing, China
| | - Zhaohui Li
- School of Medicine, Nankai University, Tianjin, China
- Department of Ophthalmology, The Third Medical Center, The Chinese People's Liberation Army General Hospital, Beijing, China
- The Chinese People's Liberation Army Medical School, Beijing, China
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Fu J, Wang Y, Tan S, Xu G, Zhou H, Xu Q, Wei S. The clinical application of critical flicker fusion frequency in demyelinating optic neuritis. ADVANCES IN OPHTHALMOLOGY PRACTICE AND RESEARCH 2021; 1:100011. [PMID: 37846319 PMCID: PMC10577832 DOI: 10.1016/j.aopr.2021.100011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 10/23/2021] [Accepted: 11/14/2021] [Indexed: 10/18/2023]
Abstract
Purpose To investigate the application of critical flicker fusion frequency (CFF) in demyelinating optic neuritis (DON). Methods A cross-sectional study. A total of 127 eyes in 69 DON patients and 63 eyes in 33 healthy control (HC) groups were included between January 2021 to September 2021 from Department of Ophthalmology, PLA General Hospital. Patients underwent best-corrected visual acuity (BCVA), visual field, optical coherence tomography (OCT), flash visual evoked potential (F-VEP), and CFF examinations. The affected eyes were divided into aquaporins 4 (AQP4-), myelin oligodendrocyte glycoprotein (MOG-), and double negative DON according to serum antibody; mild, moderate, severe degree visual impairment according to BCVA ≥ 0.5, 0.1-0.5, < 0.1; and 4 groups: < 1, 1 ∼< 3, 3 ∼ < 6 and > 6 months according to time interval from onset to CFF examination. One-way ANOVA was used to perform above subgroup analysis. The correlations between CFF and F-VEP peak time, peak value, BCVA and mean visual filed defect (MD) were analyzed in order via Pearson correlation analysis. Results he trichromatic values of red, green, and yellow in DON affected eyes were 21.83 ± 9.03, 23.66 ± 10.21, 24.09 ± 10.77 Hz, respectively, which was significantly reduced compared with the HC group (t = -14.82, -14.22, -14.00; P < 0.001). The subgroup analysis showed no significant difference between different antibody subtypes (P = 0.914 <0.848 <0.604), whereas, a significant decrease of CFF trichromatic value was found in severe visual acuity impairment group (P < 0.001). There was a significant difference in CFF- trichromatic values at different time points (P < 0.001), to be specific, CFF fluctuated under 20Hz within 3 months after onset and tended to be stable around 24-28Hz. Correlation analysis showed that the peak time of F-VEP (r = -0.486, -0.515, -0.526; P < 0.001), BVCA (r = -0.640, -0.659, -0.642; P < 0.001), were negatively correlated with CFF trichromatic values, MD and CFF were positively correlated (r = 0.486, 0.453, 0.476; P = 0.003, 0.006, 0.004). Conclusions A significant decrease of CFF value was found in DON-affected eyes, and it has a good correlation with BCVA, MD and latency of F-VEP, and can better reflect the impairment of visual function.
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Affiliation(s)
- Junxia Fu
- Department of Ophthalmology, The Chinese People's Liberation Army General Hospital & The Chinese People's Liberation Army Medical School, Beijing, China
| | - Yongping Wang
- Department of Ophthalmology, The Chinese People's Liberation Army General Hospital & The Chinese People's Liberation Army Medical School, Beijing, China
| | - Shaoying Tan
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
| | - Guangcan Xu
- Department of Ophthalmology, The Chinese People's Liberation Army General Hospital & The Chinese People's Liberation Army Medical School, Beijing, China
| | - Huanfen Zhou
- Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, Beijing, China
| | - Quangang Xu
- Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, Beijing, China
| | - Shihui Wei
- Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, Beijing, China
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Sanchez-Meza F, Torre A, Castillo-Martinez L, Sanchez-Roman S, Morales-Buenrostro LE. Evaluation of cerebral dysfunction in patients with chronic kidney disease using neuropsychometric and neurophysiological tests. Ren Fail 2021; 43:577-584. [PMID: 33757399 PMCID: PMC7993379 DOI: 10.1080/0886022x.2021.1901740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background Uremic encephalopathy is defined as cerebral dysfunction due to toxin accumulation in patients with chronic kidney disease (CKD). This condition is characterized by subtle to florid symptoms, and its clinical course is always progressive when untreated but partially reversible with renal replacement therapy. While no test exists to measure subclinical uremic encephalopathy, two tests have been validated to measure minimal hepatic encephalopathy: the critical flicker frequency (CFF) test and the psychometric hepatic encephalopathy score (PHES). Objective To use CFF and PHES to measure the prevalence of cerebral dysfunction in individuals with CKD. Methods This cross-sectional study included a total of 69 patients with stage-5 CKD. Cutoff points for minimal encephalopathy were established using existing clinical guidelines: ≤39 Hz for CFF and < −4 for PHES. All participants were also screened for cognitive function and depression. Results Eighteen cases (26.1%) of cerebral dysfunction linked to uremic encephalopathy were detected with CFF, while twelve (17.4%) were detected by PHES; only six cases (8.7%) were diagnosed by both methods. Half of the cases (50%) had diabetes, and 61% were on hemodialysis. Cognitive function scores did not differ significantly between those receiving dialysis, hemodialysis, or no renal replacement therapy. Conclusions It is essential to identify cerebral dysfunction when uremic encephalopathy is in early subclinical stages to reduce preventable events as traffic and work accidents.
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Affiliation(s)
- Fabiola Sanchez-Meza
- Department of Nephrology and Mineral Metabolism, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán", Tlalpan, Mexico
| | - Aldo Torre
- Liver Unit, Department of Gastroenterology, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán", Tlalpan, Mexico
| | - Lilia Castillo-Martinez
- Department of Clinical Nutrition, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán", Tlalpan, Mexico
| | - Sofia Sanchez-Roman
- Neurology and Psychiatry Department, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán", Tlalpan, Mexico
| | - Luis Eduardo Morales-Buenrostro
- Department of Nephrology and Mineral Metabolism, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán", Tlalpan, Mexico
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Verra DM, Sajdak BS, Merriman DK, Hicks D. Diurnal rodents as pertinent animal models of human retinal physiology and pathology. Prog Retin Eye Res 2019; 74:100776. [PMID: 31499165 DOI: 10.1016/j.preteyeres.2019.100776] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 08/27/2019] [Accepted: 08/31/2019] [Indexed: 12/12/2022]
Abstract
This presentation will survey the retinal architecture, advantages, and limitations of several lesser-known rodent species that provide a useful diurnal complement to rats and mice. These diurnal rodents also possess unusually cone-rich photoreceptor mosaics that facilitate the study of cone cells and pathways. Species to be presented include principally the Sudanian Unstriped Grass Rat and Nile Rat (Arvicanthis spp.), the Fat Sand Rat (Psammomys obesus), the degu (Octodon degus) and the 13-lined ground squirrel (Ictidomys tridecemlineatus). The retina and optic nerve in several of these species demonstrate unusual resilience in the face of neuronal injury, itself an interesting phenomenon with potential translational value.
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Affiliation(s)
- Daniela M Verra
- Department of Neurobiology of Rhythms, Institut des Neurosciences Cellulaires et Intégratives (INCI), CNRS UPR 3212, Strasbourg, France
| | | | - Dana K Merriman
- Department of Biology, University of Wisconsin Oshkosh, Oshkosh, WI, USA
| | - David Hicks
- Department of Neurobiology of Rhythms, Institut des Neurosciences Cellulaires et Intégratives (INCI), CNRS UPR 3212, Strasbourg, France.
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Study of retinal alterations in a high fat diet-induced type ii diabetes rodent: Meriones shawi. Acta Histochem 2017; 119:1-9. [PMID: 27265809 DOI: 10.1016/j.acthis.2016.05.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 05/18/2016] [Accepted: 05/19/2016] [Indexed: 12/18/2022]
Abstract
Diabetic retinopathy is a common complication of type 2 diabetes and the leading cause of blindness in adults of working age. The aim of this work was to study the repercussions of high fat diet (HFD) induced diabetes on the retina of Meriones shawi (M.sh). Two groups of six M.sh each was studied. Group I was a normal control, fed with standard laboratory granules. In Group II, rodents received a HFD of enriched laboratory granules, for a period of 3 months. Body weight and plasma glucose were determined in the two groups. Retinal sections of the two groups were stained with the Hematoxylin-Eosin. Photoreceptors were identified by immunolabeling for rhodopsin (rods) and PNA (cones). Gliosis and microglial activation were identified by immunolabeling for GFAP and Iba-1. Labeling of calretinin and parvalbumin were also carried out to study the AII amacrine cells. Retinal layers thicknesses, gliosis, and specific neural cell populations were quantified by microscopy. The body weight (+77%) and plasma glucose (+108%) were significantly greater in the HFD rodents. Three months of HFD induced a significant loss of 38.77% of cone photoreceptors, as well as gliosis and an increase of 70.67% of microglial cells. Calcium homeostatic enzymes were depleted. This work shows that HFD in Meriones shawi induces a type II diabetes-like condition that causes loss of retinal neurons and photoreceptors, as well as gliosis. Meriones shawi could be a useful experimental animal model for this physiopathology particularly in the study of retinal neuro-glial alterations in Type II diabetes.
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Simner J, Carmichael DA, Hubbard EM, Morris Z, Lawrie SM. Rates of white matter hyperintensities compatible with the radiological profile of multiple sclerosis within self-referred synesthete populations. Neurocase 2015; 21:322-30. [PMID: 24592877 DOI: 10.1080/13554794.2014.892625] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Synesthesia is an inherited condition causing unusual secondary sensations (e.g, sounds might be experienced as both auditory and visual percepts). The condition has been linked with cognitive and perceptual benefits and is considered a benign alternative form of perception. Here, we investigate self-referred synesthete populations and their rates of radiologically determined white matter hyperintensities (WMH) of a type compatible with the McDonald imaging criteria for the diagnosis of multiple sclerosis (MS). MS is a chronic condition resulting in damage to myelination surrounding nerve fibers of the central nervous system (CNS). Magnetic resonance imaging (MRI) features highly suggestive of MS without overt clinical symptoms are termed radiologically isolated syndrome (RIS). We present data showing that the shared MRI profile of MS and RIS has been significantly overrepresented in synesthetes who have participated in neuroimaging research. We present validation of the clinical and MRI status of these synesthetes and an analysis showing the significant probability their unusual numbers may not have arisen by chance. We discuss how to interpret significant data based on small case numbers and consider the implications of our findings for synesthesia's clinical status.
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Affiliation(s)
- Julia Simner
- a Department of Psychology , University of Edinburgh , Edinburgh , UK
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Nardella A, Rocchi L, Conte A, Bologna M, Suppa A, Berardelli A. Inferior parietal lobule encodes visual temporal resolution processes contributing to the critical flicker frequency threshold in humans. PLoS One 2014; 9:e98948. [PMID: 24905987 PMCID: PMC4048231 DOI: 10.1371/journal.pone.0098948] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 05/08/2014] [Indexed: 11/24/2022] Open
Abstract
The measurement of the Critical Flicker Frequency threshold is used to study the visual temporal resolution in healthy subjects and in pathological conditions. To better understand the role played by different cortical areas in the Critical Flicker Frequency threshold perception we used continuous Theta Burst Stimulation (cTBS), an inhibitory plasticity-inducing protocol based on repetitive transcranial magnetic stimulation. The Critical Flicker Frequency threshold was measured in twelve healthy subjects before and after cTBS applied over different cortical areas in separate sessions. cTBS over the left inferior parietal lobule altered the Critical Flicker Frequency threshold, whereas cTBS over the left mediotemporal cortex, primary visual cortex and right inferior parietal lobule left the Critical Flicker Frequency threshold unchanged. No statistical difference was found when the red or blue lights were used. Our findings show that left inferior parietal lobule is causally involved in the conscious perception of Critical Flicker Frequency and that Critical Flicker Frequency threshold can be modulated by plasticity-inducing protocols.
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Affiliation(s)
| | - Lorenzo Rocchi
- Department of Neurology and Psychiatry, "Sapienza", University of Rome, Rome, Italy
| | - Antonella Conte
- IRCCS Neuromed, Pozzilli, Isernia, Italy
- Department of Neurology and Psychiatry, "Sapienza", University of Rome, Rome, Italy
| | | | | | - Alfredo Berardelli
- IRCCS Neuromed, Pozzilli, Isernia, Italy
- Department of Neurology and Psychiatry, "Sapienza", University of Rome, Rome, Italy
- * E-mail:
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Costello F. The afferent visual pathway: designing a structural-functional paradigm of multiple sclerosis. ISRN NEUROLOGY 2013; 2013:134858. [PMID: 24288622 PMCID: PMC3830872 DOI: 10.1155/2013/134858] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 07/11/2013] [Indexed: 01/19/2023]
Abstract
Multiple sclerosis (MS) is a disease of the central nervous system (CNS) believed to arise from a dysfunctional immune-mediated response in a genetically susceptible host. The actual cause of MS is not known, and there is ongoing debate about whether this CNS disorder is predominantly an inflammatory versus a degenerative condition. The afferent visual pathway (AVP) is frequently involved in MS, such that one in every five individuals affected presents with acute optic neuritis (ON). As a functionally eloquent system, the AVP is amenable to interrogation with highly reliable and reproducible tests that can be used to define a structural-functional paradigm of CNS injury. The AVP has numerous unique advantages as a clinical model of MS. In this review, the parameters and merits of the AVP model are highlighted. Moreover, the roles the AVP model may play in elucidating mechanisms of brain injury and repair in MS are described.
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Affiliation(s)
- Fiona Costello
- Departments of Clinical Neurosciences and Surgery (Ophthalmology), Hotchkiss Brain Institute, University of Calgary, Canada
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An inexpensive Arduino-based LED stimulator system for vision research. J Neurosci Methods 2012; 211:227-36. [DOI: 10.1016/j.jneumeth.2012.09.012] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2012] [Revised: 09/11/2012] [Accepted: 09/13/2012] [Indexed: 11/21/2022]
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