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Karachanak-Yankova S, Serbezov D, Mihaylova M, Nikolova D, Balabanski L, Damyanova V, Antonova O, Staneva R, Ganev M, Spasova V, Rukova B, Nesheva D, Josifovska S, Stancheva M, Belejanska D, Petrova M, Mehrabian S, Traykov L, Hadjidekova S, Toncheva D. Detection of pathogenic variants in Alzheimer’s disease related genes in Bulgarian patients by pooled whole-exome sequencing. BIOTECHNOL BIOTEC EQ 2023. [DOI: 10.1080/13102818.2022.2155572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Affiliation(s)
- Sena Karachanak-Yankova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
- Department of Genetics, Faculty of Biology, Sofia University ‘St. Kliment Ohridski’, Sofia, Bulgaria
| | - Dimitar Serbezov
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Marta Mihaylova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Dragomira Nikolova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | | | - Vera Damyanova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Olga Antonova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Rada Staneva
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Mihail Ganev
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Victoria Spasova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Blaga Rukova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Desislava Nesheva
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Slavica Josifovska
- Department of Molecular Biology, Genetics and Microbiology, Faculty of Natural Sciences and Mathematics, ‘Ss. Cyril and Methodius’ University, Skopje, North Macedonia
| | - Mikaela Stancheva
- Department of Genetics, Faculty of Biology, Sofia University ‘St. Kliment Ohridski’, Sofia, Bulgaria
| | - Diana Belejanska
- Department of Neurology, University Hospital ‘Alexandrovska’, Sofia, Bulgaria
| | - Mariya Petrova
- Department of Neurology, University Hospital ‘Alexandrovska’, Sofia, Bulgaria
| | - Shima Mehrabian
- Department of Neurology, University Hospital ‘Alexandrovska’, Sofia, Bulgaria
| | - Latchezar Traykov
- Department of Neurology, University Hospital ‘Alexandrovska’, Sofia, Bulgaria
| | - Savina Hadjidekova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Draga Toncheva
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
- Bulgarian Academy of Sciences, Sofia, Bulgaria
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2
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Balabanski L, Serbezov D, Nikolova D, Antonova O, Nesheva D, Hammoudeh Z, Vazharova R, Karachanak-Yankova S, Staneva R, Mihaylova M, Damyanova V, Hadjidekova S, Toncheva D. Centenarian Exomes as a Tool for Evaluating the Clinical Relevance of Germline Tumor Suppressor Mutations. Technol Cancer Res Treat 2020; 19:1533033820911082. [PMID: 32233832 PMCID: PMC7132786 DOI: 10.1177/1533033820911082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Objectives: The aim of the present study was to evaluate the clinical relevance of mutations in
tumor suppressor genes using whole-exome sequencing data from centenarians and young
healthy individuals. Methods: Two pools, one of centenarians and one of young individuals, were constructed and
whole-exome sequencing was performed. We examined the whole-exome sequencing data of
Bulgarian individuals for carriership of tumor suppressor gene variants. Results: Of all variants annotated in both pools, 5080 (0.06%) are variants in tumor suppressor
genes but only 46 show significant difference in allele frequencies between the two
studied groups. Four variants (0.004%) are pathogenic/risk factors according to single
nucleotide polymorphism database: rs1566734 in PTPRJ, rs861539 in
XRCC3, rs203462 in AKAP10, and rs486907 in
RNASEL. Discussion: Based on their high minor allele frequencies and presence in the centenarian group, we
could reclassify them from pathogenic/risk factors to benign. Our study shows that
centenarian exomes can be used for re-evaluating the clinically uncertain variants.
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Affiliation(s)
- Lubomir Balabanski
- Department of Medical Genetics, Medical University-Sofia, Sofia, Bulgaria.,Hospital"Malinov," Sofia, Bulgaria
| | - Dimitar Serbezov
- Department of Medical Genetics, Medical University-Sofia, Sofia, Bulgaria
| | - Dragomira Nikolova
- Department of Medical Genetics, Medical University-Sofia, Sofia, Bulgaria
| | - Olga Antonova
- Department of Medical Genetics, Medical University-Sofia, Sofia, Bulgaria
| | - Desislava Nesheva
- Department of Medical Genetics, Medical University-Sofia, Sofia, Bulgaria
| | - Zora Hammoudeh
- Department of Medical Genetics, Medical University-Sofia, Sofia, Bulgaria
| | - Radoslava Vazharova
- Hospital"Malinov," Sofia, Bulgaria.,Medical Faculty, Sofia University "St Kliment Ohridski," Sofia, Bulgaria
| | | | - Rada Staneva
- Department of Medical Genetics, Medical University-Sofia, Sofia, Bulgaria
| | - Marta Mihaylova
- Department of Medical Genetics, Medical University-Sofia, Sofia, Bulgaria.,Bulgarian Academy of Science-BAS, Sofia, Bulgaria
| | - Vera Damyanova
- Department of Medical Genetics, Medical University-Sofia, Sofia, Bulgaria
| | - Savina Hadjidekova
- Department of Medical Genetics, Medical University-Sofia, Sofia, Bulgaria
| | - Draga Toncheva
- Department of Medical Genetics, Medical University-Sofia, Sofia, Bulgaria.,Bulgarian Academy of Science-BAS, Sofia, Bulgaria
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3
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Mihaylova M, Serbezov D, Balabanski L, Karachanak-Yankova S, Nikolova D, Damyanova V, Hadzhidekova S, Toncheva D. Genes predisposing to obesity emphasize G-protein coupled receptor associated pathways in healthy Bulgarian individuals. BIOTECHNOL BIOTEC EQ 2020. [DOI: 10.1080/13102818.2020.1797533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Affiliation(s)
- Marta Mihaylova
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - Dimitar Serbezov
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - Lubomir Balabanski
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
- Genome laboratory, SBALGAR Clinic Malinov, Sofia, Bulgaria
| | - Sena Karachanak-Yankova
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - Dragomira Nikolova
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - Vera Damyanova
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - Savina Hadzhidekova
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - Draga Toncheva
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
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4
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Ganev M, Balabanski L, Serbezov D, Karachanak-Yankova S, Vazharova R, Nesheva D, Hammoudeh Z, Nikolova D, Antonova O, Staneva R, Mihaylova M, Damyanova V, Hadjidekova S, Toncheva D. Prioritization of genetic variants predisposing to coronary heart disease in the Bulgarian population using centenarian exomes. BIOTECHNOL BIOTEC EQ 2019. [DOI: 10.1080/13102818.2019.1700164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Affiliation(s)
- Mihail Ganev
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Lubomir Balabanski
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
- Genome laboratory, SBALGAR Clinic Malinov, Sofia, Bulgaria
| | - Dimitar Serbezov
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Sena Karachanak-Yankova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
- Department of Genetics, Faculty of Biology, Sofia University St Kliment Ohridski, Sofia, Bulgaria
| | - Radoslava Vazharova
- Genome laboratory, SBALGAR Clinic Malinov, Sofia, Bulgaria
- Department of Biology, Medical Genetics and Microbiology, Faculty of Medicine, Sofia University St Kliment Ohridski, Sofia, Bulgaria
| | - Desislava Nesheva
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Zora Hammoudeh
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Dragomira Nikolova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Olga Antonova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Rada Staneva
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Marta Mihaylova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Vera Damyanova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Savina Hadjidekova
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
| | - Draga Toncheva
- Department of Medical Genetics, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria
- Bulgarian Academy of Sciences (BAS), Sofia, Bulgaria
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5
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Deppe A, Weber C, Mihaylova M, Sonntag D, Braun I, Liakopoulos O, Choi Y, Wahlers T. Impact of Cytokine Removal during Cardiopulmonary Bypass with CytoSorb®. Thorac Cardiovasc Surg 2018. [DOI: 10.1055/s-0038-1627841] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- A. Deppe
- Klinik und Poliklinik für Herz- und Thoraxchirurgie, Universitätsklinikum Köln, Köln, Germany
| | - C. Weber
- Klinik und Poliklinik für Herz- und Thoraxchirurgie, Universitätsklinikum Köln, Köln, Germany
| | - M. Mihaylova
- Klinik und Poliklinik für Herz- und Thoraxchirurgie, Universitätsklinikum Köln, Köln, Germany
| | - D. Sonntag
- Klinik und Poliklinik für Herz- und Thoraxchirurgie, Universitätsklinikum Köln, Köln, Germany
| | - I. Braun
- Klinik und Poliklinik für Herz- und Thoraxchirurgie, Universitätsklinikum Köln, Köln, Germany
| | - O. Liakopoulos
- Klinik und Poliklinik für Herz- und Thoraxchirurgie, Universitätsklinikum Köln, Köln, Germany
| | - Y. Choi
- Klinik und Poliklinik für Herz- und Thoraxchirurgie, Universitätsklinikum Köln, Köln, Germany
| | - T. Wahlers
- Klinik und Poliklinik für Herz- und Thoraxchirurgie, Universitätsklinikum Köln, Köln, Germany
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6
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Braun I, Deppe A, Weber C, Mihaylova M, Paunel-Görgülü A, Schlachtenberger G, Gerfer S, Djordjevic I, Choi Y, Wahlers T. Limitation of Circulating cfDNA Under the Use of a Cytokine Elimination Adsorber (CytoSorb) in Cardiac Surgery. Thorac Cardiovasc Surg 2018. [DOI: 10.1055/s-0038-1628092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- I. Braun
- Department of Cardiothoracic Surgery, University of Cologne, Cologne, Germany
| | - A. Deppe
- Department of Cardiothoracic Surgery, University of Cologne, Cologne, Germany
| | - C. Weber
- Department of Cardiothoracic Surgery, University of Cologne, Cologne, Germany
| | - M. Mihaylova
- Department of Cardiothoracic Surgery, University of Cologne, Cologne, Germany
| | - A. Paunel-Görgülü
- Department of Cardiothoracic Surgery, University of Cologne, Cologne, Germany
| | - G. Schlachtenberger
- Department of Cardiothoracic Surgery, University of Cologne, Cologne, Germany
| | - S. Gerfer
- Department of Cardiothoracic Surgery, University of Cologne, Cologne, Germany
| | - I. Djordjevic
- Department of Cardiothoracic Surgery, University of Cologne, Cologne, Germany
| | - Y. Choi
- Department of Cardiothoracic Surgery, University of Cologne, Cologne, Germany
| | - T. Wahlers
- Department of Cardiothoracic Surgery, University of Cologne, Cologne, Germany
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7
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Mihaylova M, Staneva R, Toncheva D, Pancheva M, Hadjidekova S. Benign, Pathogenic and Copy Number Variations of Unknown Clinical Significance in Patients with Congenital Malformations and Developmental Delay. Balkan J Med Genet 2017; 20:5-12. [PMID: 28924535 PMCID: PMC5596816 DOI: 10.1515/bjmg-2017-0010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The high frequency (3.0-5.0%) of congenital anomalies (CA) and intellectual disabilities (IDs), make them a serious problem, responsible for a high percentage (33.0%) of neonatal mortality. The genetic cause remains unclear in 40.0% of cases. Recently, molecular karyotyping has become the most powerful method for detection of pathogenic imbalances in patients with multiple CAs and IDs. This method is with high resolution and gives us the opportunity to investigate and identify candidate genes that could explain the genotype-phenotype correlations. This article describes the results from analysis of 81 patients with congenital malformations (CMs), developmental delay (DD) and ID, in which we utilized the CytoChip ISCA oligo microarray, 4 × 44 k, covering the whole genome with a resolution of 70 kb. In the selected group of patients with CAs, 280 copy number variations (CNVs) have been proven, 41 were pathogenic, 118 benign and 121 of unknown clinical significance (average number of variations 3.5). In six patients with established pathogenic variations, our data revealed eight pathogenic aberrations associated with the corresponding phenotype. The interpretation of the other CNVs was made on the basis of their frequency in the investigated group, the size of the variation, content of genes in the region and the type of the CNVs (deletion or duplication).
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Affiliation(s)
- M Mihaylova
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - R Staneva
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria.,Woman Health Hospital "Nadezhda", Sofia, Bulgaria
| | - D Toncheva
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria
| | - M Pancheva
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria.,Woman Health Hospital "Nadezhda", Sofia, Bulgaria
| | - S Hadjidekova
- Department of Medical Genetics, Medical Faculty, Medical University of Sofia, Sofia, Bulgaria.,Woman Health Hospital "Nadezhda", Sofia, Bulgaria
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8
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Abstract
Congenital microphthalmos and anophthalmos are rare conditions in which orbital growth is deficient. Hypoplasia of the globe affects the bony orbit (micro-orbitism), the conjunctival sac, and eyelids (microblepharism), and it may be associated with abnormalities of the entire hemifacial skeleton (hemifacial microsomia). In the present article, the authors review a series of 19 patients with microphthalmos (nine had right-sided, one had bilateral, and nine had left-sided microphthalmos) who were treated in the Orbitopalpebral Unit at Hospital Foch over a period of 15 years (follow-up, 5 months to 18 years).Orbital expansion was achieved using spherical implants (n = 13), orbital osteotomies (n = 4), and orbital expanders (n = 2). Both expanders were removed within 6 months because of failure (one infection and one rupture). The current preferred method for orbital expansion is to use serial implants in the growing orbit and osteotomies in cases of late referral or insufficient orbital volume in the older child. The target proportions of the reconstructed orbit are not planned to mirror the healthy side exactly. The inferior orbital rim is kept higher to support the orbital implant, and the orbit is kept shallow to avoid a sunken appearance. Cranial bone grafts were used to augment deficient orbital contours; they were assisted by anterior transposition of the temporalis muscle (n = 5) when additional orbital volume was required. Conjunctival sac reconstruction was achieved by the use of serial conformers placed in the conjunctival sac during the neonatal period, followed by grafts of buccal mucosa and full-thickness skin maintained in place with a tarsorrhaphy for 3 to 6 months. Eyelid reconstruction using local flaps and skin grafts proved to be necessary in cases treated by osteotomy expansion, although reconstruction was not required after expansion using serial solid shapes. The results illustrate an evolution in approach and concepts of reconstruction of the microphthalmic orbit and emphasize the need for an integrated craniofacial approach for this complex deformity.
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Affiliation(s)
- D Krastinova
- Cranio-Orbito-Palpebral Surgery Unit, Hopital Foch, Suresnes, France.
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9
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Abstract
Ablative surgery for tumors of the globe and its adnexal structures is frequently the cause of major orbitofacial deformity. Radiotherapy compounds the problem because it suppresses skeletal growth in the growing patient and induces a contraction of the remaining soft tissues in the orbit. Goals for reconstruction in these patients include the restoration of orbital structures to allow the fitting of an ocular prosthesis and the correction of distorted orbitofacial relationships. The authors present a series of 53 patients (mean age, 29 years; 28 male) who were treated over the past 18 years by composite reconstruction of the post-tumoral anophthalmic orbit. The follow-up ranged from 5 months to 18 years (mean, 7.75 years). Four patients were treated primarily (immediate reconstruction after tumor ablation), and 49 were treated secondarily (mean oncological follow-up since ablative surgery, 14.8 years). Twenty-eight patients underwent orbital enucleation (including three bilateral cases), 23 underwent orbital exenteration, and two underwent evisceration. Forty-two patients received radiotherapy, including 20 enucleation patients, 15 exenteration patients, and seven others in whom details of primary therapy were incomplete. A staged reconstruction was undertaken in each case; it considered, in turn, the bony orbital volume (orbital remodeling and cranial bone grafts), orbital contents (implant, temporalis muscle transposition, cranial bone grafts, and dermafat grafts), conjunctival sac (mucosal and skin grafts), ocular prosthesis, eyelids (local flaps and skin grafts), and additional procedures to restore orbitofacial symmetry. The authors conclude that the long-term results of post-tumoral orbital reconstruction are favorable, and they particularly recommend the use of autogenous tissues in irradiated orbits.
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Affiliation(s)
- D Krastinova
- Cranio-Orbito-Palpebral Surgery Unit, Hopital Foch, Suresnes, France.
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10
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Mihaylova M, Vassilev A. Effect of stimulus contrast uncertainty on simple reaction time. Acta Physiol Pharmacol Bulg 2001; 24:81-90. [PMID: 11098294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Both reaction time (RT) and the latency of the visually evoked potentials (VEP) to grating onset increase with increasing stimulus spatial frequency (SF). At SF higher than 5 c/deg RT increases faster than VEP latency, the difference resulting in a "central delay" (Mihaylova et al., 1999). Due to the equipment limitations, RT and VEP experiments of Mihaylova et al. (1999) differed in constancy of stimulus contrast within a sequence of trials. The present experiments were aimed at testing the assumption that the central delay is a result of contrast uncertainty effect on RT. To this end, RT were measured in condition of both constant and variable grating contrast. The stimuli were sinusoidal gratings ranging in SF from 0.5 to 16 c/deg and in contrast from 2.5 to 50%. In addition, VEP were recorded to the same stimuli in blocks of fixed contrast and the latencies of the early VEP wave were subtracted from RT. Contrast uncertainty did not affect RT at low SF, 0.5 and 2 c/deg, while increasing RT at SF higher than 5 c/deg both at low and high stimulus contrast. The results showed that the central component of RT increase at high SF is reduced but not eliminated under constant contrast condition. The uncertainty effect at high SF might be due to contrast sensitivity reduction, reduced subjective stimulus probability and differences in response strategy adopted by the subjects when contrast was constant or variable. An alternative explanation is a larger ability of low SF stimuli compared to high SF stimuli to attract visual attention.
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Affiliation(s)
- M Mihaylova
- Institute of Physiology, Bulgarian Academy of Sciences, Sofia, Bulgaria.
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11
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Misheva M, Mihaylova M, Djourelov N, Kresteva M, Krestev V, Nedkov E. Positron annihilation lifetime spectroscopy studies of irradiated poly(propylene-co-ethylene)/poly(ethylene-co-vinyl acetate) blends. Radiat Phys Chem Oxf Engl 1993 2000. [DOI: 10.1016/s0969-806x(99)00351-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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12
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Abstract
Visually evoked potentials (VEP) and reaction time (RT) were recorded under stimulation with sinusoidal gratings. Grating spatial frequency (SF) was 0.5, 5 or 12 cd and grating contrast was varied. Consistent with previous findings, both VEP latency and RT increased with the increase of grating SF and with the decrease of grating contrast. It was found, in addition, that RT and VEP latency increased by approximately the same amount when SF increased from 0.5 to 5 cd, thus suggesting that the main source of the RT delay at 5 cd in comparison with RT at 0.5 cd is of peripheral origin. However, in comparison with the data at 0.5 and 5 cd, RT at 12 cd increased much more than VEP latency. We conclude that the RT delay at high SF involves a substantial central component in addition to the peripheral delay.
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Affiliation(s)
- M Mihaylova
- Institute of Physiology, Bulgarian Academy of Sciences, Sofia, Bulgaria
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