A common framework for ambylopic, developmental and adult forms of visual crowding

Lead Research Organisation: University College London
Department Name: Psychology

Abstract

In our visual field, objects are typically easy to see when we look directly at them and difficult to see in the periphery (the 'edges' of our vision). This difference is not simply to do with resolution - even when a target object in the periphery is large enough to be seen in isolation, the placement of other objects in its immediate vicinity can render the target 'jumbled' and impossible to recognise. This is known as 'visual crowding'. It is crowding and not simple resolution that limits our object recognition over more than 95% of the visual field.

Although crowding does not affect the centre of gaze in 'normal' vision, it becomes elevated the case of strabismic amblyopia, often known as 'lazy eye'. Amblyopia is the most common cause of visual impairment in children and affects ~3% of the population. It is defined by impaired resolution in one eye that occurs despite optical correction. In addition, the amblyopic eye is also strongly affected by crowding - even when objects are large enough to be seen in isolation, vision at the centre of gaze is highly impaired in cluttered environments. Recent research suggests that the central vision of children younger than 12 is similarly affected by crowding. That is, where adults can recognise closely spaced objects when gazing directly at them, the same is not true for children. This places a significant restriction on the vision of children and processes such as their ability to learn to read. However, we know very little about it.

We have here three instances of visual crowding: in normal peripheral vision, in amblyopic eyes and in the eyes of young children. What we do not know is whether these three forms of crowding have a common underlying cause. Can we consider each in the same way, using the same theory, and thus apply the same treatments and coping strategies to overcome crowding? Our hypothesis is that crowding in all its forms represents a form of 'compulsory integration' that occurs when the brain is faced with limited resources: when the cells in our brain that process vision are insufficient in number, they pool across extended regions to compensate. The aim of this project is to compare these three forms of crowding and determine whether they fit this common framework.

The research will be conducted by psychologists, neuroscientists, orthoptists and ophthalmologists, with four specific goals. First, we will determine how crowding affects the appearance of objects. That is, do cluttered scenes look the same to children in their central vision as they do to adults in the periphery? This is central to testing the predictions of the compulsory integration theory and will lead to the development of computer models that simulate vision in these circumstances. Second, we will examine whether the peripheral field in normal vision is like the central vision of those with amblyopia - are there differences between the eyes and can we reduce them in the same way that we treat amblyopia? This creates the possibility for the 'normal' periphery to become a testing ground for new treatments of amblyopia, without the need to risk the central vision of children. Third, we will examine whether crowding is a single process in vision, or a general form of integration that affects different objects separately. For instance, does crowding affect moving objects in the same way that it affects letters? This will not only test the compulsory integration hypothesis in each instance of crowding, but also has the potential to develop new, more sensitive tests for crowding. Finally, we will scan the brains of 'normal' and amblyopic adults to measure whether the variation in crowding that occurs across the visual field follows the variation in neural resources to these same parts of the visual field. This will allow a direct test of the compulsory integration hypothesis in normal and amblyopic vision.

Technical Summary

Although it is clear that crowding occurs in three instances of vision - the normal periphery, amblyopic fovea and the developing fovea - it is not known whether these three instances arise from the same mechanism. Our aim is to test whether all three can be commonly understood as a 'compulsory integration' of the visual field, using psychophysics, computational modelling and neuroimaging.

There are four research objectives. First, one of the hallmarks of peripheral crowding is that it systematically changes the appearance of objects. We will determine whether this is also true in amblyopic and developmental crowding. By examining what children see under crowded conditions we can develop computational models of the process and compare their operation to models of adult crowding.

Second, the key feature of amblyopic crowding is that it is strong in the amblyopic eye and minimal in the fellow eye. Our pilot testing suggests that there are similar interocular differences in regions of the normal periphery. We will measure these 'amblyopic zones' and examine whether 'treatment programs', designed for amblyopia, can reduce these interocular differences in the periphery.

Third, we will examine whether crowding in each of the three instances occurs in the same way for the different modalities of vision (e.g. motion vs. colour). Crowding varies in strength across both the visual field and individuals, with amblyopia an extreme case, but it is not known whether these variations are common to all modalities. In measuring this, we will assess whether crowding is a singular process or a more distributed mechanism.

Finally, we will directly measure the neural correlates of peripheral and amblyopic crowding using functional neuroimaging. A combination of structural and functional MRI scans will measure the degree of cortical resources devoted to regions of the visual field and relate this to the strength of crowding in both the normal periphery and amblyopia.

Planned Impact

The proposed research will deliver impact in a number of key ways. Outside of the academic impacts outlined above, our efforts in understanding the causes of crowding in amblyopia will have a strong influence on clinical vision and the treatment of visual disorders. Amblyopia is one of the most common childhood disorders of vision, affecting ~3% of the population. In addition to its definitive acuity deficit, strabismic amblyopia in particular is also characterised by elevated crowding in the amblyopic eye. However, crowding is rarely highlighted as a specific therapeutic target. We suspect that significant deficits in crowding are going untreated, simply due to a lack of understanding regarding its effects. By increasing our understanding of the mechanisms of crowding, and its neural correlates in the amblyopic visual system, we will not only develop hallmarks for screening the presence of crowding but also neural markers for examining the effect of treatment programs on the reduction of crowding and its effects on the brain. This will reach not only clinicians, including orthoptists and ophthalmologists, but also the patients themselves.

Our work will also impact upon treatment programs for amblyopia. Firstly, the demonstration of 'amblyopic zones' in the normal periphery, with large interocular differences (IODs) in crowding, will allow the potential to develop 'treatment programs' to reduce these IODs. These treatment programs will mirror the 'binocular' treatments currently in development for amblyopia, which focus specifically on the training of stereo-vision (depth perception) and/or the reduction of interocular suppression. This is in contrast with current 'patching' techniques that are exclusively monocular and focus only on reducing the IOD in acuity. Because interocular suppression and impaired stereo-acuity are also believed to correlate with elevated crowding, we will specifically seek to evaluate the effectiveness of our analogous treatments in reducing the IODs in crowding (as well as acuity). This will allow the development and evaluation of these programs without the need to involve the central vision of children, which is time consuming and risky.

The development of these training programs for normal vision will then feed directly into 'binocular' treatment programs currently being developed within Moorfields Eye Hospital. I am a collaborator on this project, with Prof. Steven Dakin, which is funded by the Special Trustees of Moorfields and a UCL Impact Award. These exploratory trials are aimed at developing a binocular treatment that reduces interocular suppression through daily training. Our evaluations in the normal visual field in this project will determine which skills are likely to be most effective at being trained to reduce crowding, which will dictate the direction of the clinical trials. The impact of our findings will thus be immediate.

The project will also impact upon the screening of amblyopia. One of our aims is the further development of the Vac-Man battery of visual tests for children. These videogame-based tests are aimed at examining children's acuity, contrast sensitivity, stereo-acuity and, importantly for the project at hand, visual crowding. The use of these tests in the current project will allow their further refinement and validation as tools for clinical use. There is a great lack of age-appropriate tests for complex visual functions in children and this project would certainly fill the gap.

Further, an exciting aspect of these screening tests is their similarity of these tests to video games. Through contacts that UCL has established with game designers in Electronic Arts, I will attempt to develop these tests towards videogames designed to be distributed over the internet as tests for the screening and monitoring of crowding. The aim will be an industry collaboration that will be developed towards the end of the project.

Publications

10 25 50
 
Description Reviews on binocular therapy for amblyopia aimed at clinicians
Geographic Reach Multiple continents/international 
Policy Influence Type Influenced training of practitioners or researchers
Impact I have contributed to the production of a Cochrane Systematic Review on binocular treatments for amblyopia. This was published in 2015, and lays out the desired outcomes of any future clinical trials to evaluate Binocular treatments of amblyopia. As there are several such clinical trials in preparation at present (including our own), this will have substantial impact. We have also written a review article for the British Medical Bulletin that outlines the principles underlying these new treatments for amblyopia. This article is aimed at clinicians and intended to inform them of the nature of these new treatments.
 
Description Applied Vision Association Summer Research Scholarship
Amount £1,600 (GBP)
Organisation Applied Vision Association 
Sector Private
Country United Kingdom
Start 06/2016 
End 08/2016
 
Description Clinical visual neuroimaging at high field
Amount £125,501 (GBP)
Funding ID E180007A 
Organisation Moorfields Eye Charity 
Sector Charity/Non Profit
Country United Kingdom
Start 07/2018 
End 06/2019
 
Description Crowding in glaucoma: a likely barrier to self-referral?
Amount £57,744 (GBP)
Organisation The College of Optometrists 
Sector Academic/University
Country United Kingdom
Start 09/2018 
End 08/2021
 
Description Moorfields Eye Charity Project Grant
Amount £162,347 (GBP)
Funding ID ST 16 03 I 
Organisation Moorfields Eye Charity 
Sector Charity/Non Profit
Country United Kingdom
Start 09/2016 
End 08/2019
 
Description Phase 2a randomised controlled trial to determine safety of and adherence with a new Binocularly Balanced Viewing treatment for amblyopia compared with standard treatment
Amount £181,752 (GBP)
Organisation Action Medical Research 
Sector Charity/Non Profit
Country United Kingdom
Start 03/2018 
End 02/2020
 
Description Special Trustees of Moorfields Eye Hospital Project Grant
Amount £43,977 (GBP)
Funding ID ST1411F 
Organisation Moorfields Eye Hospital NHS Foundation Trust 
Department The Special Trustees of Moorfields Eye Hospital General Fund
Sector Charity/Non Profit
Country United Kingdom
Start 01/2015 
End 12/2017
 
Description University College London Impact Award
Amount £32,583 (GBP)
Organisation University College London 
Sector Academic/University
Country United Kingdom
Start 01/2015 
End 12/2017
 
Description University College London Travel Award
Amount £690 (GBP)
Organisation University College London 
Sector Academic/University
Country United Kingdom
Start 05/2016 
End 05/2016
 
Description Binocular treatment therapies for amblyopia 
Organisation Moorfields Eye Hospital NHS Foundation Trust
Country United Kingdom 
Sector Public 
PI Contribution I am involved in a large-scale collaboration to design a binocular treatment therapy for amblyopia. This would replace standard patching procedures with new procedures using consumer 3D glasses, with the aim to correct not only acuity/resolution but also visual crowding and stereo-vision. We have been awarded a grant from Action Medical Research. Our aim in doing so is to run a Randomised Clinical Trial of this new technology. My role is to assist in the design of the RCT and to contribute experimental program code and testing expertise for the evaluation of the new treatment therapy, as well as to prepare the grant application.
Collaborator Contribution The partners in the project are contributing statistical, psychological, orthoptic and clinical expertise in vision testing and treatment, as well as the writing of the grant application.
Impact We were awarded funding from Action Medical Research to conduct Randomised Clinical Trials that will assess the potential of new 'binocular' treatments for amblyopia. We have also written several publications outlining the general principles of this approach: Tailor, V, Bossi, M, Greenwood, JA & Dahlmann-Noor, A (2016). Childhood amblyopia: Current management and new trends. British Medical Bulletin, 119(1), 75-86. Tailor, V, Bossi, M, Bunce, C, Greenwood, JA, & Dahlmann-Noor, A. (2015). Binocular versus standard occlusion or blurring treatment for unilateral amblyopia in children aged three to eight years. Cochrane Database of Systematic Reviews, 8, CD011347. Bossi, M, Tailor, VK, Anderson, EJ, Bex, PJ, Greenwood, JA, Dahlmann-Noor, A, & Dakin, SC (2017). Binocular therapy for childhood amblyopia improves vision without breaking interocular suppression. Investigative Ophthalmology & Visual Science, 58(7), 3031-3043.
Start Year 2014
 
Description Binocular treatment therapies for amblyopia 
Organisation University College London
Country United Kingdom 
Sector Academic/University 
PI Contribution I am involved in a large-scale collaboration to design a binocular treatment therapy for amblyopia. This would replace standard patching procedures with new procedures using consumer 3D glasses, with the aim to correct not only acuity/resolution but also visual crowding and stereo-vision. We have been awarded a grant from Action Medical Research. Our aim in doing so is to run a Randomised Clinical Trial of this new technology. My role is to assist in the design of the RCT and to contribute experimental program code and testing expertise for the evaluation of the new treatment therapy, as well as to prepare the grant application.
Collaborator Contribution The partners in the project are contributing statistical, psychological, orthoptic and clinical expertise in vision testing and treatment, as well as the writing of the grant application.
Impact We were awarded funding from Action Medical Research to conduct Randomised Clinical Trials that will assess the potential of new 'binocular' treatments for amblyopia. We have also written several publications outlining the general principles of this approach: Tailor, V, Bossi, M, Greenwood, JA & Dahlmann-Noor, A (2016). Childhood amblyopia: Current management and new trends. British Medical Bulletin, 119(1), 75-86. Tailor, V, Bossi, M, Bunce, C, Greenwood, JA, & Dahlmann-Noor, A. (2015). Binocular versus standard occlusion or blurring treatment for unilateral amblyopia in children aged three to eight years. Cochrane Database of Systematic Reviews, 8, CD011347. Bossi, M, Tailor, VK, Anderson, EJ, Bex, PJ, Greenwood, JA, Dahlmann-Noor, A, & Dakin, SC (2017). Binocular therapy for childhood amblyopia improves vision without breaking interocular suppression. Investigative Ophthalmology & Visual Science, 58(7), 3031-3043.
Start Year 2014
 
Description Binocular treatment therapies for amblyopia 
Organisation University of Auckland
Country New Zealand 
Sector Academic/University 
PI Contribution I am involved in a large-scale collaboration to design a binocular treatment therapy for amblyopia. This would replace standard patching procedures with new procedures using consumer 3D glasses, with the aim to correct not only acuity/resolution but also visual crowding and stereo-vision. We have been awarded a grant from Action Medical Research. Our aim in doing so is to run a Randomised Clinical Trial of this new technology. My role is to assist in the design of the RCT and to contribute experimental program code and testing expertise for the evaluation of the new treatment therapy, as well as to prepare the grant application.
Collaborator Contribution The partners in the project are contributing statistical, psychological, orthoptic and clinical expertise in vision testing and treatment, as well as the writing of the grant application.
Impact We were awarded funding from Action Medical Research to conduct Randomised Clinical Trials that will assess the potential of new 'binocular' treatments for amblyopia. We have also written several publications outlining the general principles of this approach: Tailor, V, Bossi, M, Greenwood, JA & Dahlmann-Noor, A (2016). Childhood amblyopia: Current management and new trends. British Medical Bulletin, 119(1), 75-86. Tailor, V, Bossi, M, Bunce, C, Greenwood, JA, & Dahlmann-Noor, A. (2015). Binocular versus standard occlusion or blurring treatment for unilateral amblyopia in children aged three to eight years. Cochrane Database of Systematic Reviews, 8, CD011347. Bossi, M, Tailor, VK, Anderson, EJ, Bex, PJ, Greenwood, JA, Dahlmann-Noor, A, & Dakin, SC (2017). Binocular therapy for childhood amblyopia improves vision without breaking interocular suppression. Investigative Ophthalmology & Visual Science, 58(7), 3031-3043.
Start Year 2014
 
Description Crowding and face recognition 
Organisation Catholic University of Louvain
Country Belgium 
Sector Academic/University 
PI Contribution I am collaborating with Dr. Valerie Goffaux of the Universite Catholique de Louvain to investigate the operation of visual crowding in the context of face recognition - in particular, we are investigating whether the crowding of faces is similar to crowding in other domains, along the lines discussed in my research proposal. My role in this project is as the expert on visual crowding. Two masters student at UCL have also been involved in this research project.
Collaborator Contribution The collaboration involves Dr. Valérie Goffaux at the Catholic University of Louvain, who is an expert on face recognition and has particular expertise in the behavioural techniques used in the project.
Impact We co-supervised a masters student (Alexandra Kalpadakis-Smith), based at University College London. Her work has been completed and was presented at the European Conference on Visual Perception in Belgrade, Serbia (August 2014), with a published abstract in the journal Perception. The work has been published: Kalpadakis-Smith, AV, Goffaux, V, & Greenwood, JA (2018). Crowding for faces is determined by visual (not holistic) similarity: Evidence from judgements of eye position. Scientific Reports, 8 (12556), 1-14. The success of the collaboration is evident through the continuation of the masters student (who is currently completing a PhD studentship at UCL under my supervision, which links closely with my MRC fellowship), and the continued collaboration between myself and Dr. Valérie Goffaux (we are currently preparing a grant application to seek a postdoctoral fellow to work on similar projects). I was also recently awarded a visiting researcher position at the Université Catholique Louvain (to visit March/April 2018) where we will continue these studies and work towards further funding. Other publications are also forthcoming.
Start Year 2013
 
Description Crowding in glaucoma 
Organisation Cardiff University
Department School of Optometry and Vision Sciences
Country United Kingdom 
Sector Academic/University 
PI Contribution Based on work conducted towards my MRC Career Development Award, I was approached by a research group at Cardiff University to work on crowding effects in patients with glaucoma. I will contribute expertise in psychophysical testing and crowding effects. We co-wrote a grant and received funding from the Royal College of Optometrists to conduct this project in 2018.
Collaborator Contribution My colleagues at Cardiff University (Dr. Tony Redmond and Dr. Jennifer Acton) contribute expertise in glaucoma, ophthalmology, orthoptics and clinical testing. They will primarily conduct the studies in Cardiff.
Impact We have received funding through the Royal College of Optometrists.
Start Year 2018
 
Description Position encoding 
Organisation University College London
Country United Kingdom 
Sector Academic/University 
PI Contribution I am collaborating with Dr. Sam Solomon of the Experimental Psychology department at UCL. We have co-supervised several research students, each working on a project on the perception of position. This is related to the issues examined in my MRC fellowship and will thus link in nicely with ongoing projects there. My role is in designing experiments, programming code and providing resources for the experiments.
Collaborator Contribution The partner Dr. Sam Solomon is co-supervising students and designing experiments, as well as contributing code for the experiments.
Impact The project has thus far resulted in a conference presentation, which will soon be published as a full publication: Greenwood, JA, Lee, XK, Liu, Y, & Solomon, SG (2015). Task-specific population coding determines the perception of position. Perception, 44(Suppl), 183-184.
Start Year 2014
 
Description The neural correlates of individual differences in perception in children 
Organisation University College London
Country United Kingdom 
Sector Academic/University 
PI Contribution In conjunction with Dr. Tessa Dekker I am involved in a collaboration to examine spatial vision in children and its variation both across the visual field and as a function of age. I have contributed expertise in visual crowding effects, as well as developed several tests for this purpose. We have since gone on to examine the neural correlates of these variations using functional Magnetic Resonance Imaging. A grant written to obtain equipment to facilitate neuroimaging studies in this collaboration was awarded by the Moorfields Eye Charity.
Collaborator Contribution My partners in this project (primarily Dr. Tessa Dekker) has contributed her expertise in functional Magnetic Resonance Imaging, developing protocols to scan children with this technique and analysing the associated data.
Impact Thus far the work has resulted in a conference presentation: Dekker, T, Schwarzkopf, DS, McLean, A, Manning, C, Greenwood, JA, Nardini, M, & Sereno, MI (2016). The development of population receptive field size in visual cortex during childhood. Journal of Vision, 16(12), 206. We have also been awarded an equipment grant from the Moorfields Eye Charity to allow further neuroimaging work to take place at University College London.
Start Year 2016
 
Description The neural correlates of individual differences in spatial vision 
Organisation Ludwig Maximilian University of Munich (LMU Munich)
Department Experimental Psychology
Country Germany 
Sector Academic/University 
PI Contribution A collaboration with Dr. Sam Schwarzkopf in the department of Experimental Psychology to examine the neural correlates of individual differences in spatial vision. I contributed my psychophysical expertise towards the design and completion of behavioural tests. We are currently developing further studies to advance on our initial findings.
Collaborator Contribution Dr. Schwarzkopf conducted the functional magnetic resonance imaging tests related to our behavioural tests.
Impact Moutsiana, C, de Haas, B, Papageorgiou, A, van Dijk, JA, Balraj, A, Greenwood, JA, & Schwarzkopf, DS (2016). Cortical idiosyncrasies predict the perception of object size. Nature Communications, 7, 12110. Hughes, AE, Greenwood, JA, Finlayson, NJ, & Schwarzkopf, DS. (2018). Population receptive field estimates for motion-defined stimuli. bioRxiv, 435735.
Start Year 2015
 
Description Visual crowding in Posterior Cortical Atrophy 
Organisation University College London
Department Institute of Neurology
Country United Kingdom 
Sector Academic/University 
PI Contribution I am designing a test to further investigate crowding effects in patients with Posterior Cortical Atrophy. This is an early-onset form of Alzheimer's Disease characterised by visual symptoms, one of which may be crowding. We are currently developing the test with unaffected participants and hope to progress to pilot testing with patients soon.
Collaborator Contribution This project is being designed in conjunction with Dr. Sebastian Crutch at the UCL Institute of Neurology and the Dementia Research Centre. He is contributing his expertise in working with patients with Posterior Cortical Atrophy.
Impact This project covers topics in psychology and neuroscience and is inherently multi-disciplinary. There are no outcomes as yet.
Start Year 2015
 
Description Visual crowding in amblyopia 
Organisation Moorfields Eye Hospital NHS Foundation Trust
Country United Kingdom 
Sector Public 
PI Contribution I have designed behavioural tests to examine the nature of visual crowding effects in children with amblyopia, with an associated grant application written with myself as PI. This successful grant provides the funding for a PhD student working under my supervision on these tests. Several studies have been completed and presented as conference abstracts, which will soon progress to full publications.
Collaborator Contribution Dr. Annegret Dahlmann-Noor at Moorfields contributes her clinical management skills and experience working with patients with amblyopia. Dr. Steven Dakin contributes his experience in psychophysical testing in the context of amblyopia.
Impact Three papers have already arisen from this partnership: -Tailor, V, Bossi, M, Bunce, C, Greenwood, JA, & Dahlmann-Noor, A. (2015). Binocular versus standard occlusion or blurring treatment for unilateral amblyopia in children aged three to eight years. Cochrane Database of Systematic Reviews, 8, CD011347. -Tailor, V, Bossi, M, Greenwood, JA & Dahlmann-Noor, A (2016). Childhood amblyopia: Current management and new trends. British Medical Bulletin, 119(1), 75-86. -Bossi, M, Tailor, VK, Anderson, EJ, Bex, PJ, Greenwood, JA, Dahlmann-Noor, A, & Dakin, SC (2017). Binocular therapy for childhood amblyopia improves vision without breaking interocular suppression. Investigative Ophthalmology & Visual Science, 58(7), 3031-3043. As well several conference presentations (e.g.): -Bossi, M, Anderson, EJ, Tailor, V, Bex, PJ, Greenwood, JA, Dahlmann-Noor, A, & Dakin, SC. (2014). An exploratory study of a novel home-based binocular therapy for childhood amblyopia. Investigative Ophthalmolmology & Visual Science, 55(5), 5981 -Kalpadakis-Smith, AV, Tailor, V, Dahlmann-Noor, A, & Greenwood, JA (2016). The perceptual effects of crowding in amblyopic and peripheral vision. Journal of Vision, 16(12), 237. -Kalpadakis-Smith, AV, Tailor, V, Dahlmann-Noor, A, Schwarzkopf, DS, & Greenwood, JA (2018). The acuity and crowding deficits in strabismic amblyopia are stronger in the fovea than the visual periphery. Investigative Ophthalmology & Visual Science, 59 (9), 5960-5960. The grant written with myself as PI is also a tangible outcome, awarded by the Special Trustees of Moorfields Eye Hospital, along with a UCL Impact Award. We have similarly been funded for clinical trials related to this work, funded by Action Medical Research.
Start Year 2013
 
Description Visual crowding in amblyopia 
Organisation University of Auckland
Department Section of Epidemiology and Biostatistics
Country New Zealand 
Sector Academic/University 
PI Contribution I have designed behavioural tests to examine the nature of visual crowding effects in children with amblyopia, with an associated grant application written with myself as PI. This successful grant provides the funding for a PhD student working under my supervision on these tests. Several studies have been completed and presented as conference abstracts, which will soon progress to full publications.
Collaborator Contribution Dr. Annegret Dahlmann-Noor at Moorfields contributes her clinical management skills and experience working with patients with amblyopia. Dr. Steven Dakin contributes his experience in psychophysical testing in the context of amblyopia.
Impact Three papers have already arisen from this partnership: -Tailor, V, Bossi, M, Bunce, C, Greenwood, JA, & Dahlmann-Noor, A. (2015). Binocular versus standard occlusion or blurring treatment for unilateral amblyopia in children aged three to eight years. Cochrane Database of Systematic Reviews, 8, CD011347. -Tailor, V, Bossi, M, Greenwood, JA & Dahlmann-Noor, A (2016). Childhood amblyopia: Current management and new trends. British Medical Bulletin, 119(1), 75-86. -Bossi, M, Tailor, VK, Anderson, EJ, Bex, PJ, Greenwood, JA, Dahlmann-Noor, A, & Dakin, SC (2017). Binocular therapy for childhood amblyopia improves vision without breaking interocular suppression. Investigative Ophthalmology & Visual Science, 58(7), 3031-3043. As well several conference presentations (e.g.): -Bossi, M, Anderson, EJ, Tailor, V, Bex, PJ, Greenwood, JA, Dahlmann-Noor, A, & Dakin, SC. (2014). An exploratory study of a novel home-based binocular therapy for childhood amblyopia. Investigative Ophthalmolmology & Visual Science, 55(5), 5981 -Kalpadakis-Smith, AV, Tailor, V, Dahlmann-Noor, A, & Greenwood, JA (2016). The perceptual effects of crowding in amblyopic and peripheral vision. Journal of Vision, 16(12), 237. -Kalpadakis-Smith, AV, Tailor, V, Dahlmann-Noor, A, Schwarzkopf, DS, & Greenwood, JA (2018). The acuity and crowding deficits in strabismic amblyopia are stronger in the fovea than the visual periphery. Investigative Ophthalmology & Visual Science, 59 (9), 5960-5960. The grant written with myself as PI is also a tangible outcome, awarded by the Special Trustees of Moorfields Eye Hospital, along with a UCL Impact Award. We have similarly been funded for clinical trials related to this work, funded by Action Medical Research.
Start Year 2013
 
Description Visual crowding in nystagmus 
Organisation Moorfields Eye Hospital NHS Foundation Trust
Country United Kingdom 
Sector Public 
PI Contribution We were awarded a grant from the Moorfields Eye Charity (with myself as Principal Investigator) to examine crowding effects in patients with nystagmus. The grant involves funding for a clinically-qualified PhD student to conduct these studies under my supervision. The project involves patients with nystagmus, a common condition characterised by uncontrolled eye movements. We suspect that their vision is impaired by crowding and are currently designing tests to examine this, following the PhD student's start date in September 2016.
Collaborator Contribution Dr. Maria Theodorou has contributed her expertise in working with patients with nystagmus, and associated eye tracking analyses. Dr. Annegret Dahlmann-Noor has contributed associated clinical expertise. A PhD student (Mr. Vijay Tailor) is working on the project under my supervision.
Impact Successful grant from the Moorfields Eye Charity (for £162,349). And one conference presentation: -Tailor, V, Dahlmann-Noor, A, Theodorou, M, & Greenwood, JA (2018). Visual crowding in congenital nystagmus, sensory deficit or image motion?. Investigative Ophthalmology & Visual Science, 59 (9), 1080-1080.
Start Year 2015
 
Title Efficiency and Mechanism Evaluation for Binocular Treatments of Amblyopia 
Description We have developed a new binocular treatment therapy for amblyopia, a developmental disorder of vision that affects acuity in one eye. This condition is typically treated by patching one eye, forcing children to use their amblyopic eye. We believe that these treatments are failing to correct several additional issues associated with amblyopia (notably visual crowding and 3D stereo-vision). Our treatment uses consumer 3D shutter glasses to actively control the balance of inputs to the two eyes and thus encourage the combination of information from the two eyes. We hope this will treat the whole condition, rather than simply the acuity deficits of amblyopia. We were recently awarded funds through Action Medical Research, which will lead towards Randomised Clinical Trials. The trial will commence in 2019. 
Type Therapeutic Intervention - Physical
Current Stage Of Development Early clinical assessment
Year Development Stage Completed 2018
Development Status Under active development/distribution
Impact At this stage we have only just received funding to conduct a full evaluation, but initial results with a pilot study have been extremely successful - recently published in 2017 in Investigative Ophthalmology & Visual Science. 
 
Description London Schools Event Workshop 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Schools
Results and Impact A "Schools Event Workshop" was organised by a group of researchers at UCL, including myself. This involved a set of researchers presenting interactive workshops on research in neuroscience to high school students from 6 London academies. We presented a set of illusions and visual phenomena designed to spur interest into visual perception. The event was so successful that two subsequent events have been held for schools in Southampton and Manchester.
Year(s) Of Engagement Activity 2015