The following is a list of titles suggested by academic staff. If none of these appeal you are encouraged to come up with your own title.

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1 The following is a list of titles suggested by academic staff. If none of these appeal you are encouraged to come up with your own title. MSc DISSERTATION TITLES TITLE Inductive tissue interactions during formation of the embryonic eye Much of normal development depends on interactions between neighbouring tissues. An interaction that results in a change of one of the interacting tissues is called induction. In the eye, for example, the lens is induced to develop by the presence of the optic vesicle if there is no optic vesicle there will be no lens. This is only one example of many inductive interactions among the tissues of the developing eye. This dissertation will review the evidence for inductive interactions between different tissues within the developing eye and the nature of the molecular signals that mediate the interactions. Specification of mammalian neocortical areas The mammalian neocortex is a heterogeneous tissue that is divided into many functionally specialized regions. It contains, for example, numerous different visual areas, each seemingly computing different aspects of the visual scene. The various areas can be characterized by differing cellular architecture and different axonal inputs and outputs. This dissertation will evaluate the role of the input from the thalamus (such as the LGN) as well as intrinsic genetic influences on the parcellation of cortex into distinct regions during development. Role of white matter changes in central nervous disorders and plasticity Explanations of the neural basis of plasticity and psychiatric disorders have generally focused on changes taking place at synapses. Advances in gene profiling and in vivo imaging are however increasingly implicating changes in white matter of the brain. A number of the genes associated with psychiatric disorders are also related to the molecular biology of myelin, and white matter changes have been shown to occur in relevant fibre pathways of individuals training in complex tasks. This dissertation will focus on mechanisms by which changes in white matter structure can underlie plasticity and abnormal behaviour. Mechanisms of accommodation The mechanisms underlying accommodation have always been hotly disputed and although the Helmholtz-Fincham proposition is fairly widely accepted at present, there are still investigators who propose a range of minor and major modifications to that hypothesis. This dissertation will address the questions raised by those modifications. SUPERVISOR

2 A study of the contribution rod signals can make to colour vision. Rods represent ~ 95% of photoreceptors in the eye and are normally associated with vision at low light levels. When phototransduction is mediated by only one class of spectrally distinct photoreceptor, spectral and intensity changes of light are confounded and there is no colour vision. The classic assumption is that rod signals do not therefore contribute to colour vision and also saturate at higher light levels. Recent findings suggest that rods mediate phototrunsduction over a considerable range of light levels when cone signals are also involved. Findings from a number of other studies suggest that when the level of light adaption is appropriate, rod signals can contribute to colour vision. This dissertation aims to examine the available evidence to establish the stimulus conditions when rod signals can contribute to colour vision. How can we establish appropriate pass / fail limits of chromatic sensitivity within professional environments The conventional approach is to insist on normal colour vision within professional environments that involve visually-demanding, colour-related tasks, even when subjects with mild congenital colour deficiency can also carry out the suprathreshold colour-related tasks with the same accuracy as normal trichromats. The aim of this dissertation is to examine and compare the colour vision requirements within different professional environments and to discuss the difficulties of setting appropriate pass / fail limits. A study of the neural mechanisms that can give rise to chromatic afterimages Chromatic afterimages have been attributed to selective adaptation within the retina (mainly in photoreceptors). Some subjects, such as those suffering from the visual snow syndrome can perceive extended afterimages that may well involve adaption of neural mechanisms in the cortex. The purpose of this dissertation is to describe how afterimages are quantified and to identify the mechanisms responsible for normal and abnormal afterimages. Methods for characterizing visual loss in diseases of the retina and the optic nerve Structural changes in the retina that give rise to retinopathy can develop very slowly and go undetected for many years. Diseases of the retina that cause such changes include age-related macular degeneration, hypertension and glaucoma. Untreated diabetes can have similar effects. The purpose of this dissertation is investigate how detection of early, subclinical structural changes in the retina using the latest imaging techniques such as OCT compare with detection of changes in visual performance such as chromatic sensitivity and rapid flicker detection. Loss of visual field sensitivity and distributed attention with ageing and the effects on driving population Failure to detect peripheral stimuli when driving can be caused either by localised loss of visual field sensitivity or inability to distribute attention over the visual filed. Older subjects that focus their attention of foveal tasks often fail to notice suprathreshold peripheral stimuli. The purpose of this dissertation is to investigate the relative importance of loss of visual sensitivity and distributed

3 attention on driving performance in the elderly. Theories of visual perception in autism. Two main theories attempt to explain visual perception in autism; Weak Central Coherence and Enhanced Perceptual Function. This dissertation will discuss these two theories in terms of their strengths and weaknesses in explaining perception in autism. The genetics of autism, including potential therapeutic targets. Function of the inner and outer blood retinal barriers. Novel methods for delivering drugs to the retina. Can we justify vision screening? You will review the scientific literature surrounding vision screening to determine if there is enough evidence to justify a programme within the NHS. Longitudinal changes in structural and functional measurement in glaucoma The nature and mode of functional and structural progression in glaucoma is a subject of considerable debate in the scientific literature. Whilst there is a traditionally held viewpoint that optic disc and/or nerve fibre layer changes precede visual field changes there is, it seems, surprisingly little published evidence from well-controlled prospective studies in this area, specifically with modern perimetric and imaging techniques. At the same type plausible physiological and basic science arguments suggest that functional changes could occur in the absence of significant structural changes. This dissertation will provide a timely review of the literature in this area and consider the evidence base that may inform clinical practice. Reporting information in studies of diagnostic test accuracy in optometry and ophthalmology Diagnostic devices and techniques are an essential part of clinical practice and are the subject of much medical research. The Standards for Reporting of Diagnostic Accuracy (STARD) initiative provides guidance to make it easier for researchers, reviewers, and journal readers to evaluate the methodological quality of a diagnostic study and determine the likelihood for bias to be present in the findings. Leading scientific and medical journals are now demanding that authors of such studies adhere to the guidelines. This project will report on how well the guidelines have been implemented in leading UK optometry and ophthalmology journals. To screen or not to screen, that is the question In the belief that prevention is better than cure there is widespread enthusiasm for screening healthy populations for illness in its early stage, so that a better outcome can be achieved by more effective intervention. Indeed there might be potential for screening programmes for eye disease such as diabetic retinopathy. But is screening for disease a good idea? There is compelling evidence that screening actually diverts health resources from where they are truly needed adversely affecting individuals and populations. This dissertation will focus on some of these contentious debates, with reference to potential screening programmes for eye disease. Novel types of perimetry Perimetry is an important method for assessing a subject s visual field and is a Dr Paul Constable Dr Paul Constable Dr Paul Constable Dr Miriam Conway

4 critical component of the assessment of the patient with glaucoma. Conventional visual field tests (perimetry) use a fairly straightforward stimulus: a white light of varying intensity projected on a white background. Flicker, motion, pulsar, Gabor patches, frequency doubling, high pass resolution, rarebit and blue-on-yellow are just a few of the oddly named myriad of new test stimuli that are becoming available in clinical instruments. This dissertation will review and evaluate the scientific literature associated with these developments and report on the evidence of their use clinical utility. A review of accommodative methods in animals Humans have a very inefficient method of accommodation with a limited range. This dissertation will review the accommodative mechanisms of other animals. A discussion their lifestyles may reveal why their ability to focus is different to our own Gene therapy as a cure for ocular disease The first trials involving insertion of genes using viral vectors to cure eye disease are currently underway. What is the theoretical basis of such therapy, what are the chances of success and what are the dangers? Which eye disease might be amenable to such treatment? Will retinal transplants ever be a viable treatment for degenerative disease? After many years of failure, retinal implants are now beginning to be viable. This dissertation will review this work and consider the likelihood of transplants ever becoming main stream therapy for treating retinal disease. Will retinal prosthetics (bionic eyes) ever be a viable treatment for degenerative disease? Bionic eyes are the stuff of science fiction. However, (crude) images can now be perceived by blind people using a variety of devices. This dissertation will review these, examine how good they are, the problems inherent in their use and will discuss whether they will ever be of use clinically. Optometric management of those with autistic spectrum conditions (ASC) An estimated 1% (and rising!) of the population is estimated to suffer from an autistic spectrum condition (or disorder). They range from the profoundly autistic to those with Asperger syndrome. ASCs affect aspects of vision, notably visual search and eye movements. This dissertation will review our understanding of ASCs and identify how best an optometric examination should be geared to the needs of those with ASCs. Are optometrists any good at detecting glaucoma, and how can we get better at it? Optometrists are frequently criticised for referring too many false positives - patients referred for suspect glaucoma who are subsequently shown not to have the condition. But how fair is this criticism and what proportion of the false positive rate is attributable to the low prevalence of glaucoma allied to the limits on sensitivity and specificity of our tests for this condition, the regression to the mean effect, etc. What steps can the profession take to improve our performance in this area? A review of the effect of contact lenses on the visual field A review of ocular dominance and its application in optometry Prof. D. Edgar Prof. D. Edgar Prof. Bruce Evans Prof. Bruce Evans

5 Loss of Binocularity & Disability Several clinical conditions including amblyopia & unilateral cataract are associated with a loss of binocular visual functions. A growing concern in the management of patients with such disorders is whether they experience disabilities in daily life, as this is a key factor in treatment cost-benefit assessment. This dissertation will review experimental & clinical evidence that loss of binocularity is associated with impairments on various quality of life indices, such as reading, driving & sporting activities. Eye Dominance: What is its Functional Significance? Everyone has a preferred or dominant eye, as revealed by monocular sighting, suggesting that this has functional advantages. The possible nature of these advantages will be explored, including its relationship to another major functional asymmetry (handedness), for which opposite (left-right) dominances have been claimed to improve prowess in ball-hitting skills in sports, such as baseball & cricket. The Development of Eye-Hand Coordination Skills Reaching out to grasp objects are skilled, visually-guided actions that adults typically perform thousands of times a day. These skills are not innate. Newborn humans exhibit no coordination between eye and hand, partly because their vision is so poor and partly because they may not consider themselves to be separate from the external world. Moreover, while purposeful reaching and grasping (prehension) movements normally emerge in the first year of life and improve during infancy older children seem to experiment with different prehension strategies, before finally achieving adult-like performance around years of age. This dissertation will examine the visual and psychological factors (e.g., improving spatial vision, feedback and awareness, error-avoidance) that contribute to the development of these fundamental human behaviours. Visual and circadian deficit caused by yellow intraocular lenses The effect of glucose on the physical and optical properties of the crystalline lens The effect of correcting higher-order aberrations using contact lenses Non-invasive wavefront sensing of the human eye provides the necessary information to design corrections which minimize the monochromatic optical errors of the eye beyond simple sphere (defocus) and cylinder (astigmatism). Viable modes of correction include contact lenses, refractive surgery and intraocular lenses. Viewing conditions in which monochromatic aberrations are corrected and chromatic aberrations are avoided has been shown to improve contrast sensitivity and visual acuity. The development of technology to measure and correct the eye's higher-order aberrations raises the issue of how much visual benefit can be obtained by providing such correction with contact lenses. This dissertation explores the current literature available on correction of higher-order aberrations using contact lenses (soft and RGP). Will these "ideal" corrections lead to better vision? If so, by how much? The cornea: alternative methods for blood glucose measurements. Changes in glucose concentrations within the tear film have found to correlate to Dr Simon Grant Dr Simon Grant Dr Simon Grant Prof Chris Hull Prof Chris Hull Dr Byki Huntjens Dr Byki Huntjens

6 blood sugar levels in diabetic patients, making it an obvious choice for alternative measurements to the finger-prick test. However, is there scope to use corneal parameters for the same reason? This dissertation will discuss the acute corneal changes in Diabetes Mellitus, focussing on each individual corneal layer. Would there be a possibility to use fluctuations in e.g. (endothelial) cell size as a measure for changes in blood glucose levels or metabolic control? The dissertation los at previous published work, but should also include several hypotheses. The genetic basis of eye disease The role of the optometrist in primary eye care The causes and management of pronounced dry eye symptoms, without significant signs, in young female adults. The fact that some young females complain of very pronounced symptoms of dry eye, without any of the usual signs seen with this condition, is of interest. The reasons that the subject is young, female, an anxious personality and reporting bad symptoms which do not have a link with any observable sign needs to be investigated via the literature to see if there is a rational explanation that can be used to communicate to these patients when the problem arises. Disentangling perceptual bias from response bias in psychophysical studies of appearance. Lots of things can change how something appears; a black background may make lighter spots appear even lighter, adaptation to downward motion may make stationary things appear to rise. Your dissertation will address how experimenters have attempted to insulate their studies of these phenomena from expectation effects. How distal does consciousness reach? Discuss the evidence for and against Crick & Koch's famous conjecture that consciousness has no direct access to primary visual cortex. Use of criterion-free techniques in the clinic. In the clinic, psychophysical tests typically suffer from response bias. For example, in a visual field analysis, more conservative individuals indicate seeing the target lights less frequently than others who may have the same sensitivity. Such confounds can be eliminated with criterion-free paradigms. The problem is that criterion-free tests invariable take more time. This dissertation should review the pros, cons and the history of criterion-free techniques in optometric practice. Are multi-focal intraocular lenses better than single focus intraocular lenses? Multi-focal Intraocular lenses are thought to provide clear vision at most working distances. However many of these lenses have also been found to cause a reduction in Contrast Sensitivity and increase in glare sensitivity. The students will be required to review the advantages and disadvantages of Multi-focal lenses and conclude whether these lenses are better than single focus intraocular lenses. Recent developments low vision rehabilitation research Low vision is normally defined as binocular best corrected visual acuity less that 6/18. Low vision aids have long been the preferred choice in low vision Prof. John Lawrenson Prof. John Lawrenson Ms Judith Morris Dr Joshua Solomon Dr Joshua Solomon Dr Joshua Solomon Dr Ahalya Subramanian Dr Ahalya Subramanian

7 rehabilitation although not all low vision patients can be helped by low vision aids. There has been a lot in the news lately about Bionic Eyes and how these may be able to help visually impaired people see again. The student will review recent developments in low vision rehabilitation research with specific emphasis on bionic eyes and GPS systems for the visually impaired Imaging vs. Fields - Which one is better in the diagnosis and management of Glaucoma? Visual field measurements have long been the main stay of glaucoma diagnosis and management. Imaging technology is now available which some argue may be better a way of detecting and managing Glaucoma. The dissertation will review whether visual field measurements should be abolished or whether both fields and imaging have their own unique place in the management of Glaucoma. Dr Ahalya Subramanian