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Plasticity of fixation in patients with central vision loss

Published online by Cambridge University Press:  11 December 2009

LUMINITA TARITA-NISTOR ,
ESTHER G. GONZÁLEZ ,
SAMUEL N. MARKOWITZ  and
MARTIN J. STEINBACH
LUMINITA TARITA-NISTOR
Affiliation:
Vision Science Research Program, Toronto Western Research Institute, Toronto, Ontario, Canada
ESTHER G. GONZÁLEZ*
Affiliation:
Vision Science Research Program, Toronto Western Research Institute, Toronto, Ontario, Canada Centre for Vision Research, York University, Toronto, Ontario, Canada Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
SAMUEL N. MARKOWITZ
Affiliation:
Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
MARTIN J. STEINBACH
Affiliation:
Vision Science Research Program, Toronto Western Research Institute, Toronto, Ontario, Canada Centre for Vision Research, York University, Toronto, Ontario, Canada Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada
*
*Address correspondence and reprint requests to: Esther G. González, Vision Science Research Program, Toronto Western Research Institute, 399 Bathurst Street, FP 6-212, Toronto, Ontario, Canada M5T 2S8. E-mail: gonzalez@yorku.ca
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Abstract

The aim of this study was to explore the plasticity of fixation in patients with central vision loss. Most of these patients use preferred retinal loci (PRLs) in the healthy eccentric part of the retina to fixate, but fixation stability and retinal location are not always optimal for best visual performance. This study examined whether fixation stability and a new PRL location can be trained and whether these changes in ocular motor control transfer into better reading performance. Six patients with age-related macular degeneration participated in the study. Fixation stability measurements, microperimetry, and auditory biofeedback training were performed with the MP-1 microperimeter. The auditory biofeedback was used during five 1-h long training sessions to improve fixation and relocate the PRL. Fixation location and stability were recorded while viewing four different targets: a cross, a letter, a word, and a nine-cycle radial grating. Visual acuity was assessed with the Early Treatment Diabetic Retinopathy Study (ETDRS) chart and reading performance with the MNRead test. The results showed that all patients developed a new PRL in an optimal location for reading, and they were able to use it consistently while viewing different targets. Fixation stability improved 53% after training. Learning transferred to the old PRL even though fixation stability at this location was not trained. All these improvements in ocular motor control translated into better reading performance: reading speed improved 38% and reading acuity and critical print size gained two lines. We conclude that the ability of the ocular motor system to fixate is flexible in patients with central vision loss: a new PRL can be trained, fixation stability can be improved, and learning transfers to an untrained location. These gains in ocular motor control result in better visual performance. This property can be successfully used to optimize the residual vision of patients with central vision loss.

Keywords

Central vision lossPRLFixation stability trainingPlasticity of ocular motor system

Information

Type
Research Articles
Information
Visual Neuroscience , Volume 26 , Issue 5-6 , November 2009 , pp. 487 - 494
Copyright
Copyright © Cambridge University Press 2009

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References

Abadi, R.V. & Pantazidou, M. (1997). Monocular optokinetic nystagmus in humans with age-related maculopathy. The British Journal of Ophthalmology 81, 123–129.CrossRefGoogle ScholarPubMed
Baker, C.I., Dilks, D.D., Peli, E. & Kanwisher, N. (2008). Reorganization of visual processing in macular degeneration: Replication and clues about the role of foveal loss. Vision Research 48, 1910–1919.CrossRefGoogle ScholarPubMed
Baker, C.I., Peli, E., Knouf, N. & Kanwisher, N.G. (2005). Reorganization of visual processing in macular degeneration. The Journal of Neuroscience 19, 614–618.CrossRefGoogle Scholar
Cacho, I., Dichinson, C.M., Reeves, B.C. & Harper, R.A. (2007). Visual acuity and fixation characteristics in age-related macular degeneration. Optometry and Vision Science 84, 487–495.CrossRefGoogle ScholarPubMed
Cheung, S.H. & Legge, G.E. (2005). Functional and cortical adaptations to central vision loss. Visual Neuroscience 22, 187–201.CrossRefGoogle ScholarPubMed
Chung, S.T.L., Legge, G.E. & Cheung, S.H. (2004). Letter-recognition and reading speed in peripheral vision benefit from perceptual learning. Vision Research 44, 695–709.CrossRefGoogle ScholarPubMed
Crossland, M.D., Culham, L.E., Kabanarou, S.A. & Rubin, G.S. (2005). Preferred retinal locus development in patients with macular disease. Ophthalmology 112, 1579–1585.CrossRefGoogle ScholarPubMed
Crossland, M.D., Culham, L.E. & Rubin, G.S. (2004 a). Fixation stability and reading speed in patients with newly developed macular disease. Ophthalmic and Physiological Optics 24, 327–333.CrossRefGoogle ScholarPubMed
Crossland, M.D., Sims, M., Galbraith, R.F. & Rubin, G.S. (2004 b). Evaluation of a new quantitative technique to assess the number and extent of preferred retinal loci in macular disease. Vision Research 44, 1537–1546.CrossRefGoogle ScholarPubMed
Deruaz, A., Whatham, A.R., Mermoud, C. & Safran, A.B. (2002). Reading with multiple preferred retinal loci: Implications for training a more efficient reading strategy. Vision Research 42, 2947–2957.CrossRefGoogle ScholarPubMed
Dilks, D.D., Baker, C.I., Peli, E. & Kanwisher, N. (2009). Reorganization of visual processing in macular degeneration is not specific to the “preferred retinal locus”. The Journal of Neuroscience 29, 2768–2773.CrossRefGoogle ScholarPubMed
Duret, F., Issenhuth, M. & Safran, A.B. (1999). Combined use of several preferred retinal loci in patients with macular disorders when reading single words. Vision Research 39, 873–879.CrossRefGoogle ScholarPubMed
Fletcher, D.C. & Schuchard, R.A. (1997). Preferred retinal loci relationship to macular scotomas in a low vision population. Ophthalmology 104, 632–638.CrossRefGoogle Scholar
Fletcher, D.C., Schuchard, R.A. & Watson, G. (1999). Relative locations of macular scotomas near the PRL: Effect on low vision reading. Journal of Rehabilitation Research and Development 36, 356–364.Google ScholarPubMed
Frennesson, C. & Nilsson, S.E. (2007). The superior retina performs better than the inferior retina when reading with eccentric viewing: A comparison in normal volunteers. Acta Ophthalmologica Scandinavica 85, 868–870.CrossRefGoogle Scholar
Gilbert, C.D. (1998). Adult cortical dynamics. Physiological Reviews 78, 467–485.CrossRefGoogle ScholarPubMed
González, E.G., Teichman, J., Markowitz, S.N., Lillakas, L. & Steinbach, M.J. (2006). Fixation stability using radial gratings in patients with age-related macular degeneration. Canadian Journal of Ophthalmology 41, 333–339.CrossRefGoogle ScholarPubMed
Guez, J.-E., Le Gargasson, J.-F., Rigaudiere, F. & O’Regan, J.K. (1993). Is there a systematic location for the pseudo-fovea in patients with central scotoma? Vision Research 33, 1271–1279.CrossRefGoogle Scholar
Huxlin, K.R. (2008). Perceptual plasticity in damaged adult visual systems. Vision Research 48, 2154–2166.CrossRefGoogle ScholarPubMed
Karmarkar, U.R. & Dan, Y. (2006). Experience-dependent plasticity in adult visual cortex. Neuron 52, 577–585.CrossRefGoogle ScholarPubMed
Lei, H. & Schuchard, R.A. (1997). Using two preferred retinal loci for different lighting conditions in patients with central scotomas. Investigative Ophthalmology & Visual Science 38, 1812–1817.Google ScholarPubMed
Masuda, Y., Dumoulin, S.O., Nakadomari, S. & Wandell, B.A. (2008). V1 projection zone signals in human macular degeneration depend on task, not stimulus. Cerebral Cortex 18, 2483–2493.CrossRefGoogle Scholar
McMahon, T.T., Hansen, M. & Viana, M. (1991). Fixation characteristics in macular disease. Relationship between saccadic frequency, sequencing, and reading rate. Investigative Ophthalmology & Visual Science 32, 567–574.Google ScholarPubMed
Nilsson, U.L., Frennesson, C. & Nilsson, S.E. (1998). Location and stability of a newly established eccentric retinal locus suitable for reading, achieved through training of patients with a dense central scotoma. Optometry & Vision Science 75, 873–878.CrossRefGoogle ScholarPubMed
Nilsson, U.L., Frennesson, C. & Nilsson, S.E. (2003). Patients with AMD and a large absolute central scotoma can be trained successfully to use eccentric viewing, as demonstrated in a scanning laser ophthalmoscope. Vision Research 43, 1777–1787.CrossRefGoogle Scholar
Petre, K.L., Hazel, C.A., Fine, E.M. & Rubin, G.S. (2000). Reading with eccentric fixation is faster in inferior visual field than in left visual field. Optometry & Vision Science 77, 34–39.CrossRefGoogle ScholarPubMed
Reinhard, J., Messias, A., Dietz, K., Mackeben, M., Lakmann, R., Scholl, H.P., Apfelstedt-Sylla, E., Weber, B.H., Seeliger, M.W., Zrenner, E., & Trauzettel-Klosinski, S. (2007). Quantifying fixation in patients with Stargardt disease. Vision Research 47, 2076–2085.CrossRefGoogle ScholarPubMed
Schuchard, R.A. (2005). Preferred retinal loci and macular scotoma characteristics in patients with age-related macular degeneration. Canadian Journal of Ophthalmology 40, 303–312.CrossRefGoogle ScholarPubMed
Seiple, W., Szlyk, J.P., McMahon, T., Pulido, J. & Fishman, G.A. (2005). Eye-movement training for reading in patients with age-related macular degeneration. Investigative Ophthalmology & Visual Science 46, 2886–2896.CrossRefGoogle ScholarPubMed
Sunness, J.S., Applegate, C.A., Haselwood, D. & Rubin, G.S. (1996). Fixation patterns and reading rates in eyes with central scotomas from advanced atrophic age-related macular degeneration and Stargardt disease. Ophthalmology 103, 1458–1466.CrossRefGoogle ScholarPubMed
Sunness, J.S., Liu, T. & Yantis, S. (2004). Retinotopic mapping of the visual cortex using functional magnetic resonance imaging in a patient with central scotomas form atrophic macular degeneration. Ophthalmology 111, 1595–1598.CrossRefGoogle Scholar
Tarita-Nistor, L., González, E.G., Markowitz, S.M. & Steinbach, M.J. (2008). Fixation characteristics of patients with macular degeneration recorded with the MP-1 microperimeter. Retina 28, 125–133.CrossRefGoogle ScholarPubMed
Timberlake, G.T., Mainster, M.A., Peli, E., Augliere, R.A., Essock, E.A. & Arend, L.E. (1986). Reading with a macular scotoma. I. Retinal location of scotoma and fixation area. Investigative Ophthalmology & Visual Science 7, 1137–1147.Google Scholar
Timberlake, G.T., Sharma, M.K., Grose, S.A., Gobert, D.V., Gauch, J.M. & Maino, J.H. (2005). Retinal location of the preferred retinal locus relative to the fovea in scanning laser ophthalmoscope images. Optometry & Vision Science 82, 177–185.CrossRefGoogle Scholar
Valmaggia, C., Charlier, J. & Gottlob, I. (2001). Optokinetic nystagmus in patients with central scotomas in age related macular degeneration. The British Journal of Ophthalmology 85, 169–172.CrossRefGoogle ScholarPubMed
von Noorden, G.K. & Mackensen, G. (1962). Phenomenology of eccentric fixation. American Journal of Ophthalmology 53, 642–661.CrossRefGoogle ScholarPubMed
Wassle, H., Grunert, U., Rohrenbeck, J. & Boycott, B.B. (1990). Retinal ganglion cell density and cortical magnification factor in the primate. Vision Research 30, 1897–1911.CrossRefGoogle ScholarPubMed
White, J.M. & Bedell, H.E. (1990). The oculomotor reference in humans with bilateral macular disease. Investigative Ophthalmology and Visual Science 31, 1149–1161.Google ScholarPubMed
Whittaker, S.G., Cummings, R.W. & Swieson, L.R. (1991). Saccade control without a fovea. Vision Research 12, 2209–2218.CrossRefGoogle Scholar
Whittaker, S.G. & Lovie-Kitchin, J. (1993). Visual requirements for reading. Optometry & Vision Science 70, 54–65.CrossRefGoogle ScholarPubMed
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