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1. A systematic review on ‘Foveal Crowding’ in visually impaired children and perceptual learning as a method to reduce Crowding

Author

Huurneman Bianca, Boonstra F, Cox Ralf FA, Cillessen Antonius HN, and van Rens Ger

Subjects
Ophthalmology, RE1-994
Abstract

Abstract Background This systematic review gives an overview of foveal crowding (the inability to recognize objects due to surrounding nearby contours in foveal vision) and possible interventions. Foveal crowding can have a major effect on reading rate and deciphering small pieces of information from busy visual scenes. Three specific groups experience more foveal crowding than adults with normal vision (NV): 1) children with NV, 2) visually impaired (VI) children and adults and 3) children with cerebral visual impairment (CVI). The extent and magnitude of foveal crowding as well as interventions aimed at reducing crowding were investigated in this review. The twofold goal of this review is : [A] to compare foveal crowding in children with NV, VI children and adults and CVI children and [B] to compare interventions to reduce crowding. Methods Three electronic databases were used to conduct the literature search: PubMed, PsycINFO (Ovid), and Cochrane. Additional studies were identified by contacting experts. Search terms included visual perception, contour interaction, crowding, crowded, and contour interactions. Results Children with normal vision show an extent of contour interaction over an area 1.5–3× as large as that seen in adults NV. The magnitude of contour interaction normally ranges between 1–2 lines on an acuity chart and this magnitude is even larger when stimuli are arranged in a circular configuration. Adults with congenital nystagmus (CN) show interaction areas that are 2× larger than those seen adults with NV. The magnitude of the crowding effect is also 2× as large in individuals with CN as in individuals with NV. Finally, children with CVI experience a magnitude of the crowding effect that is 3× the size of that experienced by adults with NV. Conclusions The methodological heterogeneity, the diversity in paradigms used to measure crowding, made it impossible to conduct a meta-analysis. This is the first systematic review to compare crowding ratios and it shows that charts with 50% interoptotype spacing were most sensitive to capture crowding effects. The groups that showed the largest crowding effects were individuals with CN, VI adults with central scotomas and children with CVI. Perceptual Learning seems to be a promising technique to reduce excessive foveal crowding effects.

Published
2012
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9. An Update on the Measurement of Motor Cerebellar Dysfunction in Multiple Sclerosis

Author

Kenyon, KH, Boonstra, F, Noffs, G, Butzkueven, H, Vogel, AP, Kolbe, S, van der Walt, A, Kenyon, KH, Boonstra, F, Noffs, G, Butzkueven, H, Vogel, AP, Kolbe, S, and van der Walt, A

Abstract

Multiple sclerosis (MS) is a progressive disease that often affects the cerebellum. It is characterised by demyelination, inflammation, and neurodegeneration within the central nervous system. Damage to the cerebellum in MS is associated with increased disability and decreased quality of life. Symptoms include gait and balance problems, motor speech disorder, upper limb dysfunction, and oculomotor difficulties. Monitoring symptoms is crucial for effective management of MS. A combination of clinical, neuroimaging, and task-based measures is generally used to diagnose and monitor MS. This paper reviews the present and new tools used by clinicians and researchers to assess cerebellar impairment in people with MS (pwMS). It also describes recent advances in digital and home-based monitoring for people with MS.

Published
2023

10. ZNF408 is mutated in familial exudative vitreoretinopathy and is crucial for the development of zebrafish retinal vasculature

Author

Collin, Rob W. J., Nikopoulos, Konstantinos, Dona, Margo, Gilissen, Christian, Hoischen, Alexander, Boonstra, F. Nienke, Poulter, James A., Kondo, Hiroyuki, Berger, Wolfgang, Toomes, Carmel, Tahira, Tomoko, Mohn, Lucas R., Blokland, Ellen A., Hetterschijt, Lisette, Ali, Manir, Groothuismink, Johanne M., Duijkers, Lonneke, Inglehearn, Chris F., Sollfrank, Lea, Strom, Tim M., Uchio, Eiichi, van Nouhuys, C. Erik, Kremer, Hannie, Veltman, Joris A., van Wijk, Erwin, and Cremers, Frans P. M.

Published
2013

14. Fixel-based Analysis of Diffusion MRI: Methods, Applications, Challenges and Opportunities.

Author

Dhollander T., Clemente A., Singh M., Boonstra F., Civier O., Duque J.D., Egorova N., Enticott P., Fuelscher I., Gajamange S., Genc S., Gottlieb E., Hyde C., Imms P., Kelly C., Kirkovski M., Kolbe S., Liang X., Malhotra A., Mito R., Poudel G., Silk T.J., Vaughan D.N., Zanin J., Raffelt D., Caeyenberghs K., Dhollander T., Clemente A., Singh M., Boonstra F., Civier O., Duque J.D., Egorova N., Enticott P., Fuelscher I., Gajamange S., Genc S., Gottlieb E., Hyde C., Imms P., Kelly C., Kirkovski M., Kolbe S., Liang X., Malhotra A., Mito R., Poudel G., Silk T.J., Vaughan D.N., Zanin J., Raffelt D., and Caeyenberghs K.

Abstract

Diffusion MRI has provided the neuroimaging community with a powerful tool to acquire in-vivo data sensitive to microstructural features of white matter, up to 3 orders of magnitude smaller than typical voxel sizes. The key to extracting such valuable information lies in complex modelling techniques, which form the link between the rich diffusion MRI data and various metrics related to the microstructural organization. Over time, increasingly advanced techniques have been developed, up to the point where some diffusion MRI models can now provide access to properties specific to individual fibre populations in each voxel in the presence of multiple "crossing" fibre pathways. While highly valuable, such fibre-specific information poses unique challenges for typical image processing pipelines and statistical analysis. In this work, we review the "Fixel-Based Analysis" (FBA) framework, which implements bespoke solutions to this end. It has recently seen a stark increase in adoption for studies of both typical (healthy) populations as well as a wide range of clinical populations. We describe the main concepts related to Fixel-Based Analyses, as well as the methods and specific steps involved in a state-of-the-art FBA pipeline, with a focus on providing researchers with practical advice on how to interpret results. We also include an overview of the scope of all current FBA studies, categorized across a broad range of neuro-scientific domains, listing key design choices and summarizing their main results and conclusions. Finally, we critically discuss several aspects and challenges involved with the FBA framework, and outline some directions and future opportunities.Copyright © 2021

Published
2021

15. Fixel-based Analysis of Diffusion MRI: Methods, Applications, Challenges and Opportunities

Author

Dhollander, T, Clemente, A, Singh, M, Boonstra, F, Civier, O, Duque, JD, Egorova, N, Enticott, Peter, Fuelscher, Ian, Gajamange, S, Genc, S, Gottlieb, E, Hyde, Christian, Imms, P, Kelly, C, Kirkovski, Melissa, Kolbe, S, Liang, X, Malhotra, A, Mito, R, Poudel, G, Silk, Timothy, Vaughan, DN, Zanin, J, Raffelt, D, Caeyenberghs, Karen, Dhollander, T, Clemente, A, Singh, M, Boonstra, F, Civier, O, Duque, JD, Egorova, N, Enticott, Peter, Fuelscher, Ian, Gajamange, S, Genc, S, Gottlieb, E, Hyde, Christian, Imms, P, Kelly, C, Kirkovski, Melissa, Kolbe, S, Liang, X, Malhotra, A, Mito, R, Poudel, G, Silk, Timothy, Vaughan, DN, Zanin, J, Raffelt, D, and Caeyenberghs, Karen

Published
2021

16. Next-generation sequencing of a 40 Mb linkage interval reveals TSPAN12 mutations in patients with familial exudative vitreoretinopathy

Author

Nikopoulos, Konstantinos, Gilissen, Christian, Hoischen, Alexander, van Nouhuys, C. Erik, Boonstra, F. Nienke, Blokland, Ellen A.W., Arts, Peer, Wieskamp, Nienke, Strom, Tim M., Ayuso, Carmen, Tilanus, Mauk A.D., Bouwhuis, Sanne, Mukhopadhyay, Arijit, Scheffer, Hans, Hoefsloot, Lies H., Veltman, Joris A., Cremers, Frans P.M., and Collin, Rob W.J.

Subjects
Nucleotide sequence -- Research, Linkage (Genetics) -- Research, Gene mutations -- Research, Biological sciences
Abstract

A study applies next-generation sequencing of a 40 Mb linkage interval in affected persons to identify the gene which causes autosomal-dominant familial exudative vitreoretinopathy (FEVR). Results reveal that mutations in the TSPAN12 are associated with FEVR incidence.

Published
2010

17. Speech biometrics can predict cerebellar dysfunction in multiple sclerosis

Author

Vogel, A, Noffs, G, Boonstra, F, Perera, T, Kolbe, S, Stankovich, J, Butzkueven, H, Evans, A, Walt, AD, Vogel, A, Noffs, G, Boonstra, F, Perera, T, Kolbe, S, Stankovich, J, Butzkueven, H, Evans, A, and Walt, AD

Abstract

Objective: To objectively describe cerebellar mediated speech function using a multiparameter index that reflects pathology and quality of life in MS. Background: Cerebellar function plays a role in cognitive processing and motor control and is important for speech production. Multiple sclerosis (MS) can result in impaired cerebellar function, leading to speech deficits. These deficits can be detected by instrumental measurement. Speech as a marker of cerebellar impairment but is not well described. Method: The speech and clinical features of 85 people with MS (plus 21 matched controls) were assessed using objective acoustic analysis, validated questionnaires of quality of life and disease severity using the Scale for the Assessment and rating of Ataxia. Magnetic resonance imaging was used to measure cerebellar pathology. A regression model with eight speech variables were used to predict cerebellar function. A composite speech score was developed from the model and tested for prediction of fine motor function using the 9-hole peg test (9HPT), for correlations with imaging outcomes and self-assessed quality of life. Results: Speech timing metrics (eg. slow rate of syllable repetition, increased proportion of silence) were the strongest predictors of cerebellar impairment, alongside phonatory instability. The acoustic composite score accounted for 54% of variation in cerebellar dysfunction, was associated with cerebellar white matter volume (r=0.3, p=0.017), quality of life (r=0.5, p<0.001) and predicted an abnormal 9HPT with 85% accuracy. Conclusion: Motor cerebellar impairment in MS was reflected in an objective multi-feature speech metric.

Published
2020

18. LONGITUDINAL STUDY OF RPE65-ASSOCIATED INHERITED RETINAL DEGENERATIONS

Author

MS Oogheelkunde, Pierrache, Laurence H.M., Ghafaryasl, Babak, Khan, Muhammad I., Yzer, Susanne, van Genderen, Maria M., Schuil, José, Boonstra, F. Nienke, Pott, Jan W.R., de Faber, Jan Tjeerd H.N., Tjon-Fo-Sang, Martha J.H., Vermeer, Koenraad A., Cremers, Frans P.M., Klaver, Caroline C.W., van den Born, L. Ingeborgh, MS Oogheelkunde, Pierrache, Laurence H.M., Ghafaryasl, Babak, Khan, Muhammad I., Yzer, Susanne, van Genderen, Maria M., Schuil, José, Boonstra, F. Nienke, Pott, Jan W.R., de Faber, Jan Tjeerd H.N., Tjon-Fo-Sang, Martha J.H., Vermeer, Koenraad A., Cremers, Frans P.M., Klaver, Caroline C.W., and van den Born, L. Ingeborgh

Published
2020

23. LONGITUDINAL STUDY OF RPE65-ASSOCIATED INHERITED RETINAL DEGENERATIONS

Author

Pierrache, Laurence H. M., primary, Ghafaryasl, Babak, additional, Khan, Muhammad I., additional, Yzer, Susanne, additional, van Genderen, Maria M., additional, Schuil, José, additional, Boonstra, F. Nienke, additional, Pott, Jan W. R., additional, de Faber, Jan Tjeerd H. N., additional, Tjon-Fo-Sang, Martha J. H., additional, Vermeer, Koenraad A., additional, Cremers, Frans P. M., additional, Klaver, Caroline C. W., additional, and van den Born, L. Ingeborgh, additional

Published
2020
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27. Speech metrics, general disability, brain imaging and quality of life in multiple sclerosis.

Author

Noffs, G., Boonstra, F. M. C., Perera, T., Butzkueven, H., Kolbe, S. C., Maldonado, F., Cofre Lizama, L. Euardo, Galea, M. P., Stankovich, J., Evans, A., Walt, A., and Vogel, A. P.

Subjects
*MULTIPLE sclerosis, *BRAIN imaging, *WHITE matter (Nerve tissue), *QUALITY of life, *DISABILITIES, *HEARING impaired, *SPEECH apraxia, *VELOPHARYNGEAL insufficiency
Abstract

Background and purpose: Objective measurement of speech has shown promising results to monitor disease state in multiple sclerosis. In this study, we characterize the relationship between disease severity and speech metrics through perceptual (listener based) and objective acoustic analysis. We further look at deviations of acoustic metrics in people with no perceivable dysarthria. Methods: Correlations and regression were calculated between speech measurements and disability scores, brain volume, lesion load and quality of life. Speech measurements were further compared between three subgroups of increasing overall neurological disability: mild (as rated by the Expanded Disability Status Scale ≤2.5), moderate (≥3 and ≤5.5) and severe (≥6). Results: Clinical speech impairment occurred majorly in people with severe disability. An experimental acoustic composite score differentiated mild from moderate (P < 0.001) and moderate from severe subgroups (P = 0.003), and correlated with overall neurological disability (r = 0.6, P < 0.001), quality of life (r = 0.5, P < 0.001), white matter volume (r = 0.3, P = 0.007) and lesion load (r = 0.3, P = 0.008). Acoustic metrics also correlated with disability scores in people with no perceivable dysarthria. Conclusions: Acoustic analysis offers a valuable insight into the development of speech impairment in multiple sclerosis. These results highlight the potential of automated analysis of speech to assist in monitoring disease progression and treatment response. [ABSTRACT FROM AUTHOR]

Published
2021
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28. Development of Refractive Errors—What Can We Learn From Inherited Retinal Dystrophies?

Author

Hendriks, Michelle, Verhoeven, Virginie J M, Buitendijk, Gabriëlle H.S., Polling, Jan Roelof, Meester-Smoor, Magda A., Hofman, Albert, van Huet, Ramon A C, Klevering, B Jeroen, Bax, Nathalie M., Lambertus, Stanley, Klaver, Caroline C W, Hoyng, Carel B., Oomen, Clasien J, van Zelst-Stams, Wendy A. G., Cremers, Frans Pm, Plomp, Astrid S, van Schooneveld, Mary J., van Genderen, Mies M., Schuil, José, Boonstra, F Nienke, Schlingemann, Reinier O, Bergen, Arthur A., Pierrache, Laurence, Meester-Smoor, Magda, van den Born, L Ingeborgh, Boon, Camiel J.F., Pott, Jan W.R., van Leeuwen, Redmer, Kroes, Hester Y., de Jong-Hesse, Yvonne, Kamermans, Maarten, Ingeborgh van den Born, L., and RD5000 Consortium

Subjects
Ophthalmology, Journal Article
Abstract

Purpose It is unknown which retinal cells are involved in the retina-to-sclera signaling cascade causing myopia. As inherited retinal dystrophies (IRD) are characterized by dysfunction of a single retinal cell type and have a high risk of refractive errors, a study investigating the affected cell type, causal gene, and refractive error in IRDs may provide insight herein. Design Case-control study. Methods STUDY POPULATION: Total of 302 patients with IRD from 2 ophthalmogenetic centers in the Netherlands. REFERENCE POPULATION: Population-based Rotterdam Study-III and Erasmus Rucphen Family Study (N = 5550). Distributions and mean spherical equivalent (SE) were calculated for main affected cell type and causal gene; and risks of myopia and hyperopia were evaluated using logistic regression. Results Bipolar cell-related dystrophies were associated with the highest risk of SE high myopia 239.7; odds ratio (OR) mild hyperopia 263.2, both P

Published
2017

29. Promoting nature conservation by Dutch farmers: a governance perspective

Author

Runhaar, H. A. C., Melman, Th. C. P., Boonstra, F. G., Erisman, J. W., Horlings, L. G., de Snoo, G. R., Termeer, C. J. A. M., Wassen, M. J., Westerink, J., Arts, B. J. M., Environmental Governance, Environmental Sciences, Urban and Regional Studies Institute, Environmental Governance, Environmental Sciences, and Earth and Climate

Subjects
Economics and Econometrics, 0211 other engineering and technologies, nature conservation, WASS, Regional Development and Spatial Use, 02 engineering and technology, 010501 environmental sciences, 01 natural sciences, Forest and Nature Conservation Policy, Bos- en Natuurbeleid, SDG 15 - Life on Land, 0105 earth and related environmental sciences, agriculture, biodiversity, Natuur en samenleving, Public economics, business.industry, Corporate governance, Public Administration and Policy, Perspective (graphical), the Netherlands, Nature and society, 021107 urban & regional planning, Environmental economics, Regionale Ontwikkeling en Ruimtegebruik, Rural Sociology, governance, Agriculture, Nature Conservation, Dierecologie, Bestuurskunde, Business, Animal Ecology, nature conservation, biodiversity, agriculture, governance, the Netherlands, Rurale Sociologie, Agronomy and Crop Science, Agricultural landscapes
Abstract

Reconciling productive agricultural practices with nature conservation is not only an ecological challenge, but also a demanding matter of governance. This paper analyses the potential as well as the limitations of various governance arrangements, and explores ways to enhance the governance of nature conservation in agricultural landscapes. We assume four conditions to contribute to the performance of these arrangements: farmers should be motivated, demanded, enabled, and legitimized to participate in arrangements that promote nature conservation by farmers. We analyse 10 distinct Dutch governance arrangements in the period 2000–2016, including agri-environment schemes but also privately initiated arrangements. The arrangements target a large but unknown share of farmers and farmlands, but nature conservation ambition levels are generally low to moderate. The expected low-to-moderate performance is associated with a low-to-moderate motivation, demand, and ability. Underlying are stronger forces driving towards intensification and problems farmers face in recuperating the cost of nature conservation. New greening requirements in the EU Common Agricultural Policy and in agri-food supply chains are first, cautious steps addressing these fundamental drivers of ecological degradation. More ambitious greening requirements may contribute to a higher motivation and ability of larger groups of farmers to implement nature conservation measures.

Published
2017

34. Promoting nature conservation by Dutch farmers: a governance perspective

Author

Environmental Governance, Environmental Sciences, Runhaar, H. A. C., Melman, Th. C. P., Boonstra, F. G., Erisman, J. W., Horlings, L. G., de Snoo, G. R., Termeer, C. J. A. M., Wassen, M. J., Westerink, J., Arts, B. J. M., Environmental Governance, Environmental Sciences, Runhaar, H. A. C., Melman, Th. C. P., Boonstra, F. G., Erisman, J. W., Horlings, L. G., de Snoo, G. R., Termeer, C. J. A. M., Wassen, M. J., Westerink, J., and Arts, B. J. M.

Published
2017

38. Pathophysiology of MS tremor: an fMRI study

Author

Boonstra, F, Noffs, G, Perera, T, Shanahan, C, Vogel, A, Evans, A, Butzkueven, H, van der Walt, A, Kolbe, S, Boonstra, F, Noffs, G, Perera, T, Shanahan, C, Vogel, A, Evans, A, Butzkueven, H, van der Walt, A, and Kolbe, S

Published
2017

39. Development of Refractive Errors—What Can We Learn From Inherited Retinal Dystrophies?

Author

MS Oogheelkunde, Infection & Immunity, Genetica Klinische Genetica, Child Health, Hendriks, Michelle, Verhoeven, Virginie J M, Buitendijk, Gabriëlle H.S., Polling, Jan Roelof, Meester-Smoor, Magda A., Hofman, Albert, van Huet, Ramon A C, Klevering, B Jeroen, Bax, Nathalie M., Lambertus, Stanley, Klaver, Caroline C W, Hoyng, Carel B., Oomen, Clasien J, van Zelst-Stams, Wendy A. G., Cremers, Frans Pm, Plomp, Astrid S, van Schooneveld, Mary J., van Genderen, Mies M., Schuil, José, Boonstra, F Nienke, Schlingemann, Reinier O, Bergen, Arthur A., Pierrache, Laurence, Meester-Smoor, Magda, van den Born, L Ingeborgh, Boon, Camiel J.F., Pott, Jan W.R., van Leeuwen, Redmer, Kroes, Hester Y., de Jong-Hesse, Yvonne, Kamermans, Maarten, Ingeborgh van den Born, L., RD5000 Consortium, MS Oogheelkunde, Infection & Immunity, Genetica Klinische Genetica, Child Health, Hendriks, Michelle, Verhoeven, Virginie J M, Buitendijk, Gabriëlle H.S., Polling, Jan Roelof, Meester-Smoor, Magda A., Hofman, Albert, van Huet, Ramon A C, Klevering, B Jeroen, Bax, Nathalie M., Lambertus, Stanley, Klaver, Caroline C W, Hoyng, Carel B., Oomen, Clasien J, van Zelst-Stams, Wendy A. G., Cremers, Frans Pm, Plomp, Astrid S, van Schooneveld, Mary J., van Genderen, Mies M., Schuil, José, Boonstra, F Nienke, Schlingemann, Reinier O, Bergen, Arthur A., Pierrache, Laurence, Meester-Smoor, Magda, van den Born, L Ingeborgh, Boon, Camiel J.F., Pott, Jan W.R., van Leeuwen, Redmer, Kroes, Hester Y., de Jong-Hesse, Yvonne, Kamermans, Maarten, Ingeborgh van den Born, L., and RD5000 Consortium

Published
2017

40. Putative digenic inheritance of heterozygous RP1L1 and C2orf71 null mutations in syndromic retinal dystrophy

Author

Liu, Yangfan P., Bosch, Daniëlle G.M., Siemiatkowska, Anna M., Rendtorff, Nanna Dahl, Boonstra, F. Nienke, Möller, Claes, Tranebjærg, Lisbeth, Katsanis, Nicholas, Cremers, Frans P.M., Liu, Yangfan P., Bosch, Daniëlle G.M., Siemiatkowska, Anna M., Rendtorff, Nanna Dahl, Boonstra, F. Nienke, Möller, Claes, Tranebjærg, Lisbeth, Katsanis, Nicholas, and Cremers, Frans P.M.

Abstract

Background: Retinitis pigmentosa (RP) is the most common cause of inherited retinal degeneration and can occur in non-syndromic and syndromic forms. Syndromic RP is accompanied by other symptoms such as intellectual disability, hearing loss, or congenital abnormalities. Both forms are known to exhibit complex genetic interactions that can modulate the penetrance and expressivity of the phenotype. Materials and methods: In an individual with atypical RP, hearing loss, ataxia and cerebellar atrophy, whole exome sequencing was performed. The candidate pathogenic variants were tested by developing an in vivo zebrafish model and assaying for retinal and cerebellar integrity. Results: Exome sequencing revealed a complex heterozygous protein-truncating mutation in RP1L1, p.[(Lys111Glnfs*27; Gln2373*)], and a heterozygous nonsense mutation in C2orf71, p.(Ser512*). Mutations in both genes have previously been implicated in autosomal recessive non-syndromic RP, raising the possibility of a digenic model in this family. Functional testing in a zebrafish model for two key phenotypes of the affected person showed that the combinatorial suppression of rp1l1 and c2orf71l induced discrete pathology in terms of reduction of eye size with concomitant loss of rhodopsin in the photoreceptors, and disorganization of the cerebellum. Conclusions: We propose that the combination of heterozygous loss-of-function mutations in these genes drives syndromic retinal dystrophy, likely through the genetic interaction of at least two loci. Haploinsufficiency at each of these loci is insufficient to induce overt pathology.

Published
2017

42. Development of Refractive Errors—What Can We Learn From Inherited Retinal Dystrophies?

Author

Hendriks, Michelle, primary, Verhoeven, Virginie J.M., additional, Buitendijk, Gabriëlle H.S., additional, Polling, Jan Roelof, additional, Meester-Smoor, Magda A., additional, Hofman, Albert, additional, Kamermans, Maarten, additional, Ingeborgh van den Born, L., additional, Klaver, Caroline C.W., additional, van Huet, Ramon A., additional, Klevering, B. Jeroen, additional, Bax, Nathalie M., additional, Lambertus, Stanley, additional, Hoyng, Carel B., additional, Oomen, Clasien J., additional, van Zelst-Stams, Wendy A., additional, Cremers, Frans P., additional, Plomp, Astrid S., additional, van Schooneveld, Mary J., additional, van Genderen, Mies M., additional, Schuil, José, additional, Boonstra, F. Nienke, additional, Schlingemann, Reinier O., additional, Bergen, Arthur A., additional, Pierrache, Laurence, additional, Meester-Smoor, Magda, additional, van den Born, L. Ingeborgh, additional, Boon, Camiel J., additional, Pott, Jan W.R., additional, van Leeuwen, Redmer, additional, Kroes, Hester Y, additional, and de Jong-Hesse, Yvonne, additional

Published
2017
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44. Correction: Corrigendum: The expanding clinical phenotype of Bosch-Boonstra-Schaaf optic atrophy syndrome: 20 new cases and possible genotype–phenotype correlations

Author

Chen, Chun-An, primary, Bosch, Daniëlle G M, additional, Cho ScM, Megan T, additional, Rosenfeld, Jill A, additional, Shinawi, Marwan, additional, Lewis, Richard Alan, additional, Mann, John, additional, Jayakar, Parul, additional, Payne, Katelyn, additional, Walsh, Laurence, additional, Moss, Timothy, additional, Schreiber, Allison, additional, Schoonveld, Cheri, additional, Monaghan, Kristin G, additional, Elmslie, Frances, additional, Douglas, Ganka, additional, Boonstra, F Nienke, additional, Millan, Francisca, additional, Cremers, Frans P M, additional, McKnight, Dianalee, additional, Richard, Gabriele, additional, Juusola, Jane, additional, Kendall, Fran, additional, Ramsey, Keri, additional, Anyane-Yeboa, Kwame, additional, Malkin, Elfrida, additional, Chung, Wendy K, additional, Niyazov, Dmitriy, additional, Pascual, Juan M, additional, Walkiewicz, Magdalena, additional, Veluchamy, Vivekanand, additional, Li, Chumei, additional, Hisama, Fuki M, additional, de Vries, Bert B A, additional, and Schaaf, Christian, additional

Published
2017
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47. The expanding clinical phenotype of Bosch-Boonstra-Schaaf optic atrophy syndrome: 20 new cases and possible genotype–phenotype correlations

Author

Chen, Chun-An, primary, Bosch, Daniëlle G.M., additional, Cho, Megan T., additional, Rosenfeld, Jill A., additional, Shinawi, Marwan, additional, Lewis, Richard Alan, additional, Mann, John, additional, Jayakar, Parul, additional, Payne, Katelyn, additional, Walsh, Laurence, additional, Moss, Timothy, additional, Schreiber, Allison, additional, Schoonveld, Cheri, additional, Monaghan, Kristin G., additional, Elmslie, Frances, additional, Douglas, Ganka, additional, Boonstra, F. Nienke, additional, Millan, Francisca, additional, Cremers, Frans P.M., additional, McKnight, Dianalee, additional, Richard, Gabriele, additional, Juusola, Jane, additional, Kendall, Fran, additional, Ramsey, Keri, additional, Anyane-Yeboa, Kwame, additional, Malkin, Elfrida, additional, Chung, Wendy K., additional, Niyazov, Dmitriy, additional, Pascual, Juan M., additional, Walkiewicz, Magdalena, additional, Veluchamy, Vivekanand, additional, Li, Chumei, additional, Hisama, Fuki M., additional, de Vries, Bert B.A., additional, and Schaaf, Christian, additional

Published
2016
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48. Development and validation of a high-speed stereoscopic eyetracker.

Author

Goossens, Jeroen, Barsingerhorn, Annemiek D., and Boonstra, F. Nienke

Abstract

Traditional video-based eyetrackers require participants to perform an individual calibration procedure, which involves the fixation of multiple points on a screen. However, certain participants (e.g., people with oculomotor and/or visual problems or infants) are unable to perform this task reliably. Previous work has shown that with two cameras one can estimate the orientation of the eyes' optical axis directly. Consequently, only one calibration point is needed to determine the deviation between an eye's optical and visual axes. We developed a stereo eyetracker with two USB 3.0 cameras and two infrared light sources that can track both eyes at ~ 350 Hz for eccentricities of up to 20°. A user interface allows for online monitoring and threshold adjustments of the pupil and corneal reflections. We validated this tracker by collecting eye movement data from nine healthy participants and compared these data to eye movement records obtained simultaneously with an established eyetracking system (EyeLink 1000 Plus). The results demonstrated that the two-dimensional accuracy of our portable system is better than 1°, allowing for at least ± 5-cm head motion. Its resolution is better than 0.2° (SD), and its sample-to-sample noise is less than 0.05° (RMS). We concluded that our stereo eyetracker is a valid instrument, especially in settings in which individual calibration is challenging. [ABSTRACT FROM AUTHOR]

Published
2018
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50. Oefening baart kunst: Crowdingtraining verbetert visuele functies van slechtziende kinderen

Author

Huurneman, Bianca, Cox, Ralf F.A, Boonstra, F. Nienke, and Developmental Psychology

Subjects
genetic structures, eye diseases
Abstract

Crowding is a visual perceptual phenomenon that refers to impaired ability to recognize a suprathreshold object when it is presented in the vicinity of other objects. Crowding therefore poses a limit on object recognition. The phenomenon is regarded to be one of the reasons why young children need large textbook letters. Several studies have provided evidence that crowding imposes a bottleneck on reading speed, and reading long words. Thus, crowding influences visual perception and object recognition in young children. Recent studies show that crowding is stronger in children with visual impairment than in children with normal vision. But which factors are responsible for these strong crowding effects? And how can we reduce crowding in children with visual impairment for whom low visual acuity in itself already poses a bottleneck on object recognition? This review article tries to answer these questions. This knowledge is useful for educational psychologists, because crowding can interfere with the acquisition of academic skills and reading. Keywords: crowding, learning, visual impairment, visual acuity, visual attention.

Published
2014

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