Arnold J Wilkins- DPhil
- Professor Emeritus at University of Essex
Arnold J Wilkins
- DPhil
- Professor Emeritus at University of Essex
About
376
Publications
171,688
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
14,441
Citations
Introduction
Arnold J Wilkins is Professor Emeritus at the University of Essex. He does research on clinical vision, migraine, reading, text design and lighting.
Current institution
Additional affiliations
October 1974 - December 1997
Position
- Senior Researcher - Special Appointment
Description
- formerly the MRC Applied Psychology Unit
January 1997 - September 2020
October 1972 - September 1974
Publications
Publications (376)
The main binocular vision and accommodative anomalies are considered in turn: strabismus, heterophoria, convergence insufficiency, binocular instability, accommodative insufficiency, and accommodative infacility. For each of these conditions, any associations with reading difficulties are reviewed. Each review includes an assessment as to whether t...
This chapter starts with reflections on visual stress and the multifactorial nature of reading difficulties. Priorities for research are outlined, both concerning vision and reading difficulties. The various research designs that have been used are described together with some of their pitfalls. Suggestions for eye care practice are offered, noting...
In this chapter we describe the various coloured filters that are used in the assessment and treatment of patients: how many are needed and why, and what their physical characteristics should be. Other tools that are used in the investigation of visual stress are also briefly described, including adaptations to digital displays (computer screens),...
The various possible mechanisms whereby coloured filters might improve symptoms and reading speed are reviewed. The chapter starts with the straightforward mechanisms that are well-understood in terms of physics and biology. These include light scatter, retinal mechanisms, ocular accommodation, binocular vision anomalies, magnocellular-dorsal (M-D)...
In this chapter we review studies in which precision tints have been used in a variety of neurological disorders, including photosensitive epilepsy, autism, migraine, cluster headache, visual snow, stroke, multiple sclerosis and concussion (mild brain trauma). Whilst the evidence regarding these topics is preliminary and indicative, the effects of...
The components of a clinical optometric examination are explained, and how they relate to ocular health, visual fields, colour vision and refractive error. The possible associations with reading difficulty and techniques for treatment are set out. It is concluded that refractive errors, visual acuity, and ocular pathology are not correlates of deve...
Research on the use of coloured filters for people with visual stress is described in this chapter. There is a sizeable body of research, and the chapter concentrates on systematic reviews and randomised controlled trials. The use of coloured lenses in those with reading difficulties remains controversial, and reasons for the controversy are discus...
The historical background to the use of colour in assisting with reading is summarised in this chapter. Recent developments in the optometric use of coloured filters were facilitated by modern techniques for tinting plastic ophthalmic lenses. These techniques permit the selection of coloured lenses defined by a spectral transmission that suits an i...
This chapter starts with an introduction outlining the evidence-based approach, and a flow-chart summarising the typical procedure for investigating visual factors that may be relevant to reading difficulties. The limitations of a diagnosis of exclusion, as applied to visual stress, are discussed. Symptoms are considered in detail, noting that many...
There are several visual pathways that convey different types of information to the brain. We review evidence that in dyslexic individuals there is a deficit in one of these pathways, the magnocellular-dorsal (transient; M-D) pathway. A large body of research supports an M-D deficit as a correlate of dyslexia, but the evidence that the deficit play...
In this chapter the structure of the book is laid out, together with the underlying rationale. Types of learning difficulty and their relation to reading difficulties are described. The key clinical visual deficits that can accompany reading difficulties-binocular instability and visual stress-are introduced. The associated symptoms and signs are d...
A wide range of treatments of reading difficulty have been proposed and marketed, often with little appropriate evaluation. Several that relate to vision are discussed in this chapter, including the training of saccadic and pursuit eye movements, treatment of ocular dominance, some elements of behavioural optometry, and cerebellar function (balance...
Appendix 1: Guidance for eye care professionals
concerning publicity on dyslexia, visual stress, and
related conditions
Appendix 2: Information to help publishers
Appendix 3: Additional resources
The ability to discern the content of the view through a window is referred to as view clarity. It is often overlooked in the design process, and the methods of shading daylight can affect window views. We conducted a narrative review of building standards and the scientific literature to better understand how shades can be designed so as to retain...
Flicker and patterns of stripes in the modern environment can evoke visual illusions, discomfort migraine, and seizures. We measured reading speed while striped and less striped texts were illuminated with LED lights. In Experiment 1, the lights flickered at 60 Hz and 120 Hz compared to 60 kHz (perceived as steady light). In Experiment 2, the light...
Purpose
Astigmatism blurs the retinal image of a circular spot along a particular orientation rendering it an elliptical shape. Astigmatic patients demonstrate adaptation to residual astigmatic blur that may affect their discrimination between oval and circular targets. The Wilkins Egg and Ball Test (WEBT) was created to detect altered visual perce...
The human vestibular system is crucial for motion perception, balance control, and various higher cognitive functions. Exploring how the cerebral cortex responds to vestibular signals is not only valuable for a better understanding of how the vestibular system participates in cognitive and motor functions but also clinically significant in diagnosi...
Background
Excessive and persistent fear of clusters of holes, also known as trypophobia, has been suggested to reflect cortical hyperexcitability and may be associated with mental health risks. No study, however, has yet examined these associations in representative epidemiological samples.
AimsTo examine the prevalence of trypophobia in a populat...
Much of the neural machinery of the early visual cortex, from the extraction of local orientations to contextual modulations through lateral interactions, is thought to have developed to provide a sparse encoding of contour in natural scenes, allowing the brain to process efficiently most of the visual scenes we are exposed to. Certain visual stimu...
Temporal light modulation (TLM) describes variations in light output from a light source or lighting system and can be a characteristic of their normal operation. TLM at 100 or 120 Hz can disrupt eye movements and reduce visual performance compared to 40 kHz, but little is known of the effects between those frequencies. Such evidence could provide...
Photophobia is a complex disorder that can involve aversion not simply to bright light but to spatial patterns, colour and flicker. The use of tinted lenses to reduce photophobia in neurological diseases has a long history. Rarely has the possibility that different individuals might require lenses individually tailored to their needs been considere...
Visual stress is thought to reflect cortical excitability and has been associated with many neurological, neuropsychiatric, and neurodevelopmental conditions. However, its relationships with symptoms of depression and anxiety have not yet been elucidated. We conducted two separate studies to first examine visual stress in a longitudinal community s...
The historical background to the use of colour to assist reading is summarised in this chapter. Recent developments in the optometric use of coloured filters are the result of techniques for tinting plastic ophthalmicSeeSeeoptometrist
lenses that permit the selection of spectral transmission for coloured glasses on an individual basis. The two new...
The components of a clinical optometric examination are explained, and how they relate to ocular health, visual fields, colour vision and refractive error. The possible associations with reading difficulty and techniques for treatment are set out. It is concluded that refractive errors, visual acuity, and ocular pathology are not correlates of deve...
There are several visual pathways that convey different types of information to the brain. We review evidence that in dyslexic individuals there is a deficit in one of these pathways, the magnocellular pathway-dorsal (transient; M-D) pathway. A large body of research supports an M-D deficit as a correlate of dyslexia, but the evidence that the defi...
In this chapter we review studies in which precision tints have been used in a variety of neurological disorders, including photosensitive epilepsy, autism, migraine, cluster headache, visual snow, stroke, multiple sclerosis and concussion. Whilst the evidence regarding these topics is preliminary and indicative rather than conclusive, the effects...
The main binocular vision and accommodative anomalies are considered in turn: strabismus, heterophoria, convergence insufficiency, binocular instability, accommodative insufficiency, and accommodative infacility. For each of these conditions, any associations with reading difficulties are reviewed, including their cause. The treatment of these cond...
A wide range of treatments of reading difficulty have been proposed and marketed, often with little appropriate evaluation. Several that relate to vision are discussed in this chapter, including the training of saccadic and pursuit eye movements, treatment of ocular dominance, some elements of behavioural optometry, and cerebello-vestibular (balanc...
The chapter describes research on the use of coloured filters for people with visual stress. There is a large body of research, and the chapter concentrates on systematic reviews and randomised controlled trials. The use of coloured lenses in those with reading difficulties remains controversial, and reasons for the controversy are discussed. It is...
This chapter starts with an introduction outlining the evidence-based approach, and a flow-chart summarising the typical procedure for investigating visual factors that may be relevant to reading difficulties. The limitations of a diagnosis of exclusion, as applied to visual stress, is discussed. Symptoms are considered in detail, noting that many...
This chapter is aimed at researchers and clinicians. It starts with reflections on visual stress. The multifactorial nature of reading difficulties is noted. Recommendations are made for research on both these topics, priorities for research, both concerning vision and reading difficulties and noting some of the pitfalls of research in this field t...
In this chapter we describe the various coloured filters that are used in the assessment and treatment of patients: how many are needed and why, and what their physical characteristics should be. Other tools that are used in the investigation of visual stress are also briefly described, including adaptations to digital displays (computer screens),...
The various possible mechanisms whereby coloured filters might improve symptoms and reading speed are reviewed. The chapter starts with the straightforward mechanisms that are well-understood in terms of physics and biology. These include light scatter, retinal mechanisms, ocular accommodation (ocular), binocular vision anomalies, magnocellular-dor...
5 Collaborator; independent researcher 6 Collaborator; University of Essex Handout: www.researchgate, Bruce JW Evans for regular tweets on optometric research DISCLOSURE The speaker has received funding for lectures, key opinion leader/product feedback, and research from:
Light flashes, patterns, or color changes can provoke seizures in up to 1 in 4000 persons. Prevalence may be higher because of selection bias. The Epilepsy Foundation reviewed light‐induced seizures in 2005. Since then, images on social media, virtual reality, three‐dimensional (3D) movies, and the Internet have proliferated. Hundreds of studies ha...
Visual discomfort is related to the statistical regularity of visual images. The contribution of luminance contrast to visual discomfort is well understood and can be framed in terms of a theory of efficient coding of natural stimuli, and linked to metabolic demand. While color is important in our interaction with nature, the effect of color on vis...
Migraine is a common neurological disorder characterized by recurrent episodes of headache, frequently accompanied by various reversible neurological disturbances. Some migraine patients experience visually triggered migraine headache, and most attacks of migraine with aura are associated with the disturbance of vision and photophobia, suggesting a...
Background
The Wilkins Rate of Reading Test (WRRT) enables rapid measurement of reading speed using text passages that have no semantic content and demand minimal word recognition skills. It is suited to applications where the primary interest is in the influence of visual and ocular motor factors on reading rate.
Methods
We obtained estimates of...
Visual discomfort is related to the statistical regularity of visual images. The contribution
of luminance contrast to visual discomfort is well understood and can be framed in terms
of a theory of efficient coding of natural stimuli, and linked to metabolic demand. While
color is important in our interaction with nature, the effect of color on vis...
Effect of lighting on pattern related visual stress in individuals with specific learning disability
Authors: Krithica Srinivasan1, Peter M. Allen2, Gopee Krishnan3, Arnold Wilkins4
1. Department of Optometry, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, India
2. Vision and Hearing Sciences Research Centre...
Sensory stimuli can induce seizures in patients with epilepsy and predisposed subjects. Visual stimuli are the most common triggers, provoking seizures through an abnormal response to light or pattern. Sensitive patients may intentionally provoke their seizures through visual stimuli. Self-induction methods are widely described in photo-sensitive p...
Photophobia (fear of light) occurs in a wide range of ophthalmic, neurological and behavioural conditions, the most common of which is migraine. The visual discomfort associated with migraine can occur not only in response to bright light but also flicker, spatial pattern and colour. The principles that underlie the discomfort are explored and meth...
Photophobia is one of the most common symptoms in migraine, and the underlying mechanism is uncertain. The discovery of the intrinsically-photosensitive retinal ganglion cells which signal the intensity of light on the retina has led to discussion of their role in the pathogenesis of photophobia. In the current review, we discuss the relationship b...
The human visual system evolved to process images from nature. Natural images include images of jungles, deserts and woodlands, but despite the very obvious differences in the image content, all such images have in common three important properties. First, there is little flicker; second, there is a characteristic luminance structure, which can be...
Uncomfortable images generally have a particular spatial structure, which deviates from a reciprocal relationship between amplitude and spatial frequency (f) in the Fourier domain (1/f). Although flickering patterns with similar temporal structure also appear uncomfortable, the discomfort is affected by not only the amplitude spectrum but also the...
Background
Trypophobia is a common condition in which sufferers are averse to images of small holes arranged in clusters.
Methods
We used photo-plethysmography to examine cardiovascular correlates and near infrared spectroscopy to examine cortical correlates of the phenomenon in order to validate the Trypophobia Questionnaire and explore the sever...
A masked randomised control design compared the effectiveness of precision ophthalmic tints in improving the recognition of emotion in Autism Spectrum Disorders (ASD). Fourteen children aged 10–14 with ASD and 14 control children matched on verbal and non-verbal IQ, wore spectacles with coloured lenses to complete two tasks that involved the observ...
New building materials and design technologies such as design parameterisation allow for the creation of unusual architectural elements composed of spatially repetitive patterns. Images with specific spatial properties, as from repetitive patterns, may cause psychological and physiological reactions, in some cases leading to severe discomfort, head...
Objective
We studied the color of lighting chosen as comfortable for reading by individuals with migraine and controls. We explored the effects of the chosen color on visual performance.
Background
It has been reported that individuals who experience migraine with aura choose, as comfortable for reading, light that is more strongly saturated in...
1. The speed with which text can be read is determined in part by the spatial regularity and similarity of vertical letter strokes as assessed by the height of the first peak in the horizontal autocorrelation of the text. The height of this peak was determined for two passages in 20 fonts. The peak was unaffected by the size of the text or its cont...
Professor Arnold Wilkins looks into the impact of strip lighting on vision and how the use of colours may mitigate its negative effects.
The speed with which text can be read is determined in part by the spatial regularity and similarity of vertical letter strokes as assessed by the height of the first peak in the horizontal autocorrelation of the text. The height of this peak was determined for two passages in 20 fonts. The peak was unaffected by the size of the text or its content...
: We investigated contrast processing in relation to visual comfort from coloured light in individuals with migraine. In Experiment 1, 24 individuals who experienced migraine with aura (MA), 15 migraine without aura (MO), and 23 healthy controls, identified which of four patterns, one in each quadrant, had the greatest contrast. Although there were...
Light-emitting diode-based lighting systems are now applied in both general lighting and automotive lighting. Time-modulated control methods such as pulse width modulation are frequently applied as a dimming method. This paper presents the characteristics of the visibility of the phantom array effect according to luminance, chromaticity and angular...
The rate of reading test in which randomly ordered common words are read aloud has found use in optometric and educational practice as a means of assessing visual aspects of reading largely independently of comprehension. English and Kannada versions of the rate of reading test were administered to 761 children aged between 9 and 15 years. These ch...
Spatial images with unnatural amplitude spectra tend to appear uncomfortable. Analogous effects are found in the temporal domain, yet discomfort in flickering patterns is also strongly dependent on the phase spectrum. Here we examined how discomfort in temporal flicker is affected by adaptation to different amplitude and phase spectra. Adapting and...
A flickering light can be seen during a saccadic eye movement as a pattern of contours known as a phantom array. On repeated pairs of trials, observers made saccades across a narrow (1 arc minutes), bright (10−4 cd/m²) source of flickering light and were required to detect the phantom array. On one of each pair of trials, chosen at random, the ligh...
This volume presents authoritative and up-to-date research in colour studies by specialists across a wide range of academic disciplines, including vision science, psychology, psycholinguistics, linguistics, anthropology, onomastics, philosophy, archaeology and design. The chapters have been developed from papers and posters presented at the Progres...
Like the rest of the world, the landscape of architecture has changed in many of the Arabian Gulf cities with the introduction of new design technologies and parameterisation methods. Some of the contemporary designs of building facades comprise of perforated walls generated by computer software. Such perforations are similar in their shapes and na...
Like the rest of the world, the landscape of architecture has changed in many of the Arabian Gulf cities with the introduction of new design technologies and parameterisation methods. Some of the contemporary designs of building facades comprise of perforated walls generated by computer software. Such perforations are similar in their shapes and na...
Visual patterns are all around us. Despite overwhelming evidence from the visual sciences that some visual patterns, in particular highly-geometric and repetitive patterns, can be aversive, patterns in our visual environment are rarely considered with regard to their impact on brain, behaviour and well-being. Yet, attempts toward developing healthi...
Purpose:
Kannada, one of the Dravidian languages, is the official language of Karnataka state of India. There is a need for a test using Kannada words that can assess visual aspects of reading independently of syntactic and semantic knowledge.
Methods: :
A test of reading rate in Kannada was developed following the design principles of the Wilki...
The purpose of the study was to assess the repeatability of clinical assessments with the Intuitive Colorimeter, a repeatability classified as "poor" in a previous study. Patients underwent assessments with the Intuitive Colorimeter in two studies. In each study, one published by Suttle et al 1 and the other described herein, assessments were under...
Purpose: Kannada, one of the Dravidian languages, is the official language of Karnataka state of India. There is a need for a test using Kannada words that can assess visual aspects of reading independently of syntactic and semantic knowledge. Methods: A test of reading rate in Kannada was developed following the design principles of the Wilkins Ra...
Visual discomfort refers to discomfort or pain in or around the eyes, often associated with headache and/or nausea, and sometimes accompanied by signs such as red, itchy or watering eyes. The lighting conditions likely to cause visual discomfort are insufficient light for the task at hand, dramatic differences in illuminance around the task, shadow...
Chromatic gratings can be uncomfortable to view and can evoke a large haemodynamic response. Both the discomfort and the amplitude of the haemodynamic response are monotonic to the perceptual difference in the colour of the component bars of the grating, as registered by the separation in their chromaticity in the CIE 1976 UCS diagram. Individuals...
Relatively little is known about the contribution of colour to visual discomfort, or the impact of discomfort on cortical processing. Certain coloured gratings can be uncomfortable to view, and in extreme cases, can evoke migraines, or seizures in those susceptible. We previously found the discomfort to coloured gratings can be predicted simply fro...
Flickering lights can be uncomfortable to look at and can induce seizures in observers with photosensitive epilepsy. However, the temporal characteristics contributing to these effects are not fully known. In the spatial domain, one identified source of visual discomfort is when images have Fourier amplitude spectra that deviate from the natural (∼...
Scenes from nature share in common certain statistical properties. Images with these properties can be processed efficiently by the human brain. Patterns with unnatural statistical properties are uncomfortable to look at, and are processed inefficiently, according to computational models of the visual cortex. Consistent with such putative computati...
Purpose:
Visual stress (VS) is characterised by symptoms of visual perceptual distortions and eyestrain when viewing text, symptoms that are alleviated by individually prescribed coloured filters. A recent review supports the existence of VS and its treatment, but noted that controversy remains, in part due to inconsistencies in the diagnosis of t...
The article explains the concept of pattern glare, evidence for its impact and how practitioners may be influential in assisting when problems result
Certain visual disturbances make it difficult to read text and have been attributed to visual stress, also called “pattern-related visual stress”. 12 Children with ASD, 12 children with Tourette's syndrome and without ASD and 12 controls, all matched on age and non verbal ability, participated in an experiment exploring sensory behaviours and visua...
Stripes have been known to cause visual stress (Wilkins and Evans, 2007).
The occurrences of stripes in nature often signify the possibility of poison (e.g.,
venomous snake, centipede) (Cole and Wilkins, 2011). Most alphabets contain
vertical stripes. English and German sentences with words containing more
vertical stripes can increase the reading...
Can the visual system learn to adapt particularly rapidly to large, commonly occurring changes in input? Every time one takes off or puts on a pair of glasses, the statistics of visual input change dramatically. It would be advantageous if vision could adapt especially efficiently to such changes, but whether it does so remains unknown. We tested w...
The visual system continuously adapts to the environment, allowing it to perform optimally in a changing visual world. One large change occurs every time one takes off or puts on a pair of spectacles. It would be advantageous for the visual system to learn to adapt particularly rapidly to such large, commonly occurring events, but whether it can do...
Visual stress should not be confused with dyslexia. It refers to symptoms of discomfort and perceptual distortion that have a neurological origin. Pattern 2 of the Pattern Glare Test can be used to elicit symptoms of visual stress, but pattern 3 is of relatively little clinical use. The symptoms sometimes remit with tints, but studies consistently...
Background Paralympic sports provide opportunities for those who have an impairment that might otherwise be a barrier to participation in regular sporting competition. Rifle shooting represents an ideal sport for persons with vision impairment (VI) because the direction of the rifle can be guided by auditory information when vision is impaired. How...
Following traumatic brain injury symptoms such as photophobia, headache, and visual perceptual difficulties may persist. Sixty-one individuals whose symptoms had persisted for more than 3 months were asked to read with and without a coloured filter chosen as best improving comfort and clarity from among 12 different colours. Reading speed improved...
Questions
Question (1)
This study showed that drifting patterns are NOT epileptogenic whereas stationary, vibrating or phase-reversing patterns are. We proposed that this was because with drifting patterns the contours moved into and out of overlapping receptive fields, providing excitation, but with no synchronisation. We hypothesised that the other patterns result in synchronised activity because of directionally sensitive neurons; in the case of stationary patterns the micro saccades provide the movement.
As I understand it, your studies show that synchronisation is necessary at the inception of the epileptic discharge?
