Visual Perception in Migraine: a Narrative Review
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12 Retina Gabriele K
299 12 Retina Gabriele K. Lang and Gerhard K. Lang 12.1 Basic Knowledge The retina is the innermost of three successive layers of the globe. It comprises two parts: ❖ A photoreceptive part (pars optica retinae), comprising the first nine of the 10 layers listed below. ❖ A nonreceptive part (pars caeca retinae) forming the epithelium of the cil- iary body and iris. The pars optica retinae merges with the pars ceca retinae at the ora serrata. Embryology: The retina develops from a diverticulum of the forebrain (proen- cephalon). Optic vesicles develop which then invaginate to form a double- walled bowl, the optic cup. The outer wall becomes the pigment epithelium, and the inner wall later differentiates into the nine layers of the retina. The retina remains linked to the forebrain throughout life through a structure known as the retinohypothalamic tract. Thickness of the retina (Fig. 12.1) Layers of the retina: Moving inward along the path of incident light, the individual layers of the retina are as follows (Fig. 12.2): 1. Inner limiting membrane (glial cell fibers separating the retina from the vitreous body). 2. Layer of optic nerve fibers (axons of the third neuron). 3. Layer of ganglion cells (cell nuclei of the multipolar ganglion cells of the third neuron; “data acquisition system”). 4. Inner plexiform layer (synapses between the axons of the second neuron and dendrites of the third neuron). 5. Inner nuclear layer (cell nuclei of the bipolar nerve cells of the second neuron, horizontal cells, and amacrine cells). 6. Outer plexiform layer (synapses between the axons of the first neuron and dendrites of the second neuron). -
Hereditary Nystagmus in Early Childhood
J Med Genet: first published as 10.1136/jmg.7.3.253 on 1 September 1970. Downloaded from Journal of Medical Genetics (1970). 7, 253. Hereditary Nystagmus in Early Childhood BRIAN HARCOURT* Nystagmus is defined as a rhythmic involuntary clinical characteristics of various types of hereditary movement of the eyes, and as an acquired pheno- nystagmus and the techniques which are available menon arising in later childhood or in adult life is to differentiate between 'idiopathic' nystagmus and usually a symptom of serious neurological or laby- nystagmus as a symptom of an occult disorder of the rinthine disease; in such cases the movements of the visual apparatus in early childhood, some descrip- eyes commonly produce subjective symptoms of tion of the modes of inheritance and of the long- objects moving in the visual panorama (oscillopsia). term visual prognosis are given in the various Nystagmus may also be 'congenital', or, more categories of infantile nystagmus which can be so accurately, may first be observed within a few weeks defined. of birth when the infant begins to attempt to fix and to follow visually stimulating targets by means of Character of Nystagmus conjugate movements of the eyes. In such cases, Though it is not usually possible to arrive at the nystagmus may persist throughout life, but even an exact diagnosis of the cause of nystagmus by ob- at a later stage there is always a complete absence of servation of the eye movements alone, a great deal of the symptom of oscillopsia. Nystagmus which useful information can be obtained by such a study. -
Treacher Collins Prize Essay the Significance of Nystagmus
Eye (1989) 3, 816--832 Treacher Collins Prize Essay The Significance of Nystagmus NICHOLAS EVANS Norwich Introduction combined. The range of forms it takes, and Ophthalmology found the term v!to"[<xy!too, the circumstances in which it occurs, must be like many others, in classical Greece, where it compared and contrasted in order to under described the head-nodding of the wined and stand the relationships between nystagmus of somnolent. It first acquired a neuro-ophthal different aetiologies. An approach which is mological sense in 1822, when it was used by synthetic as well as analytic identifies those Goodl to describe 'habitual squinting'. Since features which are common to different types then its meaning has been refined, and much and those that are distinctive, and helps has been learned about the circumstances in describe the relationship between eye move which the eye oscillates, the components of ment and vision in nystagmus. nystagmus, and its neurophysiological, Nystagmus is not properly a disorder of eye neuroanatomic and neuropathological corre movement, but one of steady fixation, in lates. It occurs physiologically and pathologi which the relationship between eye and field cally, alone or in conjunction with visual or is unstable. The essential significance of all central nervous system pathology. It takes a types of nystagmus is the disturbance in this variety of different forms, the eyes moving relationship between the sensory and motor about one or more axis, and may be conjugate ends of the visual-oculomotor axis. Optimal or dysjugate. It can be modified to a variable visual performance requires stability of the degree by external (visual, gravitational and image on the retina, and vision is inevitably rotational) and internal (level of awareness affected by nystagmus. -
Macular Dystrophies Mimicking Age-Related Macular Degeneration
Progress in Retinal and Eye Research 39 (2014) 23e57 Contents lists available at ScienceDirect Progress in Retinal and Eye Research journal homepage: www.elsevier.com/locate/prer Macular dystrophies mimicking age-related macular degeneration Nicole T.M. Saksens a,1,2,7, Monika Fleckenstein b,1,3,7, Steffen Schmitz-Valckenberg b,4,7, Frank G. Holz b,3,7, Anneke I. den Hollander a,5,7, Jan E.E. Keunen a,5,7, Camiel J.F. Boon a,c,d,5,6,7, Carel B. Hoyng a,*,7 a Department of Ophthalmology, Radboud University Medical Centre, Philips van Leydenlaan 15, 6525 EX Nijmegen, The Netherlands b Department of Ophthalmology, University of Bonn, Ernst-Abbe-Str. 2, Bonn, Germany c Oxford Eye Hospital and Nuffield Laboratory of Ophthalmology, John Radcliffe Hospital, University of Oxford, West Wing, Headley Way, Oxford OX3 9DU, United Kingdom d Department of Ophthalmology, Leiden University Medical Centre, Albinusdreef 2, 2333 ZA Leiden, The Netherlands article info abstract Article history: Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in the elderly Available online 28 November 2013 population in the Western world. AMD is a clinically heterogeneous disease presenting with drusen, pigmentary changes, geographic atrophy and/or choroidal neovascularization. Due to its heterogeneous Keywords: presentation, it can be challenging to distinguish AMD from several macular diseases that can mimic the Age-related macular degeneration features of AMD. This clinical overlap may potentially lead to misdiagnosis. In this review, we discuss the AMD characteristics of AMD and the macular dystrophies that can mimic AMD. The appropriate use of clinical Macular dystrophy and genetic analysis can aid the clinician to establish the correct diagnosis, and to provide the patient Differential diagnosis Retina with the appropriate prognostic information. -
Localisation of Visual Hallucinations
BRITISH MEDICAL JOURNAL 16 JULY 1977 147 of hypothermia; the duration of cardiac arrest; and the disturbances of sleep or consciousness.4 Hallucinations may be promptness and correctness of treatment. Peterson's pessi- evoked by sensory deprivation, but other factors are usually mistic report from California,8 in which all 15 near-drowned present; thus the "black-patch" delirium that may follow children who had fits, fixed dilated pupils, flaccidity, and loss cataract extraction in the elderly probably results from sensory Br Med J: first published as 10.1136/bmj.2.6080.147 on 16 July 1977. Downloaded from of pain sensation suffered severe anoxic encephalopathy, deprivation and mild senile brain changes and is more frequent may be explained by the high water temperatures there. In when hearing is also impaired.5 warm water the protective effect of hypothermia against brain Hallucinations may be due to focal lesions. Past experiences, damage would be missing. In contrast was the case described the quality of eidetic imagery, and psychodynamic "actors in Trondheim, Norway,9 in which a 5-year-old fell through influence the content of organic hallucinosis,6 and it would be ice in fresh water with an outside temperature of 10° below unwise to lean too heavily on the occurrence and nature of zero centigrade. He was in the water for 22 minutes and was hallucinosis in localising intracranial lesions. Visual hallucina- brought out apparently dead, with widely dilated pupils and tions are a relatively infrequent accompaniment oflesions ofthe bluish white skin. He was warmed up (the method was not calcarine cortex (Brodmann's area 17), which has few thalamo- described) and-despite the risks noted above-was given cortical connections; yet they may occur as a false-localising external cardiac massage without suffering ventricular symptom of frontal or subtentorial lesions. -
39Th Annual Meeting
North American Neuro-Ophthalmology Society 39th Annual Meeting February 9–14, 2013 Snowbird Ski Resort • Snowbird, Utah POSTER PRESENTATIONS Tuesday, February 12, 2013 • 6:00 p.m. – 9:30 p.m. Authors will be standing by their posters during the following hours: Odd-Numbered Posters: 6:45 p.m. – 7:30 p.m. Even-Numbered Posters: 7:30 p.m. – 8:15 p.m. The Tour of Posters has been replaced with Distinguished Posters. The top-rated posters this year are marked with a “*” in the Syllabus and will have a ribbon on their poster board. Poster # Title Presenting Author 1* Redefining Wolfram Syndrome in the Molecular Era Patrick Yu-Wai-Man Management and Outcomes of Idiopathic Intracranial Hypertension with Moderate-Severe 2* Rudrani Banik Visual Field Loss: Pilot Data for the Surgical Idiopathic Intracranial Hypertension Treatment Trial Correlation Between Clinical Parameters And Diffusion-Weighted Magnetic Resonance 3* David M. Salvay Imaging In Idiopathic Intracranial Hypertension 4* Contrast Sensitivity Visual Acuity Defects in the Earliest Stages of Parkinsonism Juliana Matthews 5* Visual Function and Freedom from Disease Activity in a Phase 3 Trial for Relapsing Multiple Sclerosis Laura J. Balcer Dimensions of the Optic Nerve Head Neural Canal Using Enhanced Depth Imaging Optical 6* Kevin Rosenberg Coherence Tomography in Non-Arteritic Ischemic Optic Neuropathy Compared to Normal Subjects Eye Movement Perimetry: Evaluation of Saccadic Latency, Saccadic Amplitude, and Visual 7* Matthew J. Thurtell Threshold to Peripheral Visual Stimuli in Young Compared With Older Adults 9* Advanced MRI of Optic Nerve Drusen: Preliminary Findings Seth A. Smith 10* Clinical Features of OPA1-Related Optic Neuropathy: A Retrospective Case Series Philip M. -
The Pharmacological Treatment of Nystagmus: a Review
Review The pharmacological treatment of nystagmus: a review Rebecca Jane McLean & Irene Gottlob† Ophthalmology Group, University of Leicester, UK 1. Introduction 2. Acquired nystagmus Nystagmus is an involuntary, to-and-fro movement of the eyes that can result in a reduction in visual acuity and oscillopsia. Mechanisms that cause 3. Infantile nystagmus nystagmus are better understood in some forms, such as acquired periodic 4. Other treatments used in alternating nystagmus, than in others, for example acquired pendular nystagmus nystagmus, for which there is limited knowledge. Effective pharmacological 5. Conclusion treatment exists to reduce nystagmus, particularly in acquired nystagmus 6. Expert opinion and, more recently, infantile nystagmus. However, as there are very few randomized controlled trials in the area, most pharmacological treatment options in nystagmus remain empirical. Keywords: 3,4-diaminopyridine, acquired nystagmus, acquired pendular nystagmus, baclofen, downbeat nystagmus, gabapentin, infantile nystagmus, memantine, multiple sclerosis, periodic alternating nystagmus, upbeat nystagmus Expert Opin. Pharmacother. (2009) 10(11):1805-1816 1. Introduction The involuntary, to-and-fro oscillation of the eyes in pathological nystagmus can occur in the horizontal, vertical and/or torsional plane and be further classified into a jerk or pendular waveform [1]. Nystagmus leads to reduced visual acuity due to the excessive motion of images on the retina, and also the movement of images away from the fovea [2]. As the desired target falls further from the centre of the fovea, receptor density decreases and therefore the ability to perceive detail is reduced [3]. Visual acuity also declines the faster the target moves across the fovea [4]. Three main mechanisms stabilize the line of sight (to static targets) so that the image we see is fixed and clear. -
The Effects of Cognition on Pain Perception (Prepared for Anonymous Review.)
I think it’s going to hurt: the effects of cognition on pain perception (Prepared for anonymous review.) Abstract. The aim of this paper is to investigate whether, or to what extent, cognitive states (such as beliefs or intentions) influence pain perception. We begin with an examination of the notion of cognitive penetration, followed by a detailed description of the neurophysiological underpinnings of pain perception. We then argue that some studies on placebo effects suggest that there are cases in which our beliefs can penetrate our experience of pain. Keywords: pain, music therapy, gate-control theory, cognitive penetration, top-down modularity, perceptual learning, placebo effect 1. Introduction Consider the experience of eating wasabi. When you put wasabi on your food because you believe that spicy foods are tasty, the stimulation of pain receptors in your mouth can result in a pleasant experience. In this case, your belief seems to influence your perceptual experience. However, when you put wasabi on your food because you incorrectly believe that the green paste is mint, the stimulation of pain receptors in your mouth can result in a painful experience rather than a pleasant one. In this case, your belief that the green paste is mint does not seem to influence your perceptual experience. The aim of this paper is to investigate whether, or to what extent, cognitive states (such as beliefs) influence pain perception. We begin with an examination of the notion of cognitive penetration and its theoretical implications using studies in visual perception. We then turn our attention to the perception of pain by considering its neurophysiological underpinnings. -
Subliminal Afterimages Via Ocular Delayed Luminescence: Transsaccade Stability of the Visual Perception and Color Illusion
ACTIVITAS NERVOSA SUPERIOR Activitas Nervosa Superior 2012, 54, No. 1-2 REVIEW ARTICLE SUBLIMINAL AFTERIMAGES VIA OCULAR DELAYED LUMINESCENCE: TRANSSACCADE STABILITY OF THE VISUAL PERCEPTION AND COLOR ILLUSION István Bókkon1,2 & Ram L.P. Vimal2 1Doctoral School of Pharmaceutical and Pharmacological Sciences, Semmelweis University, Budapest, Hungary 2Vision Research Institute, Lowell, MA, USA Abstract Here, we suggest the existence and possible roles of evanescent nonconscious afterimages in visual saccades and color illusions during normal vision. These suggested functions of subliminal afterimages are based on our previous papers (i) (Bókkon, Vimal et al. 2011, J. Photochem. Photobiol. B) related to visible light induced ocular delayed bioluminescence as a possible origin of negative afterimage and (ii) Wang, Bókkon et al. (Brain Res. 2011)’s experiments that proved the existence of spontaneous and visible light induced delayed ultraweak photon emission from in vitro freshly isolated rat’s whole eye, lens, vitreous humor and retina. We also argue about the existence of rich detailed, subliminal visual short-term memory across saccades in early retinotopic areas. We conclude that if we want to understand the complex visual processes, mere electrical processes are hardly enough for explanations; for that we have to consider the natural photobiophysical processes as elaborated in this article. Key words: Saccades Nonconscious afterimages Ocular delayed bioluminescence Color illusion 1. INTRODUCTION Previously, we presented a common photobiophysical basis for various visual related phenomena such as discrete retinal noise, retinal phosphenes, as well as negative afterimages. These new concepts have been supported by experiments (Wang, Bókkon et al., 2011). They performed the first experimental proof of spontaneous ultraweak biophoton emission and visible light induced delayed ultraweak photon emission from in vitro freshly isolated rat’s whole eye, lens, vitreous humor, and retina. -
Phosphene Perception Is Due to the Ultra-Weak Photon Emission Produced in Various Parts of the Visual System: Glutamate in the Focus
Zurich Open Repository and Archive University of Zurich Main Library Strickhofstrasse 39 CH-8057 Zurich www.zora.uzh.ch Year: 2016 Phosphene perception is due to the ultra-weak photon emission produced in various parts of the visual system: glutamate in the focus Császár, Noémi ; Scholkmann, Felix ; Salari, Vahid ; Szőke, Henrik ; Bókkon, István Abstract: Phosphenes are experienced sensations of light, when there is no light causing them. The physiological processes underlying this phenomenon are still not well understood. Previously, we proposed a novel biopsychophysical approach concerning the cause of phosphenes based on the assumption that cellular endogenous ultra-weak photon emission (UPE) is the biophysical cause leading to the sensation of phosphenes. Briefly summarized, the visual sensation of light (phosphenes) is likely to be duetothe inherent perception of UPE of cells in the visual system. If the intensity of spontaneous or induced photon emission of cells in the visual system exceeds a distinct threshold, it is hypothesized that it can become a conscious light sensation. Discussing several new and previous experiments, we point out that the UPE theory of phosphenes should be really considered as a scientifically appropriate and provable mechanism to explain the physiological basis of phosphenes. In the present paper, we also present our idea that some experiments may support that the cortical phosphene lights are due to the glutamate-related excess UPE in the occipital cortex. DOI: https://doi.org/10.1515/revneuro-2015-0039 Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-126012 Journal Article Published Version Originally published at: Császár, Noémi; Scholkmann, Felix; Salari, Vahid; Szőke, Henrik; Bókkon, István (2016). -
Visual Perceptual Skills
Super Duper® Handy Handouts!® Number 168 Guidelines for Identifying Visual Perceptual Problems in School-Age Children by Ann Stensaas, M.S., OTR/L We use our sense of sight to help us function in the world around us. It helps us figure out if something is near or far away, safe or threatening. Eyesight, also know as visual perception, refers to our ability to accurately identify and locate objects in our environment. Visual perception is an important component of vision that contributes to the way we see and interpret the world. What Is Visual Perception? Visual perception is our ability to process and organize visual information from the environment. This requires the integration of all of the body’s sensory experiences including sight, sound, touch, smell, balance, and movement. Most children are able to integrate these senses by the time they start school. This is important because approximately 75% of all classroom learning is visual. A child with even mild visual-perceptual difficulties will struggle with learning in the classroom and often in other areas of life. How Are Visual Perceptual Problems Diagnosed? A child with visual perceptual problems may be diagnosed with a visual processing disorder. He/she may be able to easily read an eye chart (acuity) but have difficulty organizing and making sense of visual information. In fact, many children with visual processing disorders have good acuity (i.e., 20/20 vision). A child with a visual-processing disorder may demonstrate difficulty discriminating between certain letters or numbers, putting together age-appropriate puzzles, or finding matching socks in a drawer. -
AN OT's Toolbox : Making the Most out of Visual Processing and Motor Processing Skills
AN OT’s Toolbox : Making the Most out of Visual Processing and Motor Processing Skills Presented by Beth Kelley, OTR/L, MIMC FOTA 2012 By Definition Visual Processing Motor Processing is is the sequence of steps synonymous with Motor that information takes as Skills Disorder which is it flows from visual any disorder characterized sensors to cognitive by inadequate development processing.1 of motor coordination severe enough to restrict locomotion or the ability to perform tasks, schoolwork, or other activities.2 1. http://en.wikipedia.org/wiki/Visual_ processing 2. http://medical-dictionary.thefreedictionary.com/Motor+skills+disorder Visual Processing What is Visual Processing? What are systems involved with Visual Processing? Is Visual Processing the same thing as vision? Review general anatomy of the eye. Review general functions of the eye. -Visual perception and the OT’s role. -Visual-Motor skills and why they are needed in OT treatment. What is Visual Processing “Visual processing is the sequence of steps that information takes as it flows from visual sensors to cognitive processing1” 1. http://en.wikipedia.org/wiki/Visual_Processing What are the systems involved with Visual Processing? 12 Basic Processes are as follows: 1. Vision 2. Visual Motor Processing 3. Visual Discrimination 4. Visual Memory 5. Visual Sequential Memory 6. Visual Spatial Processing 7. Visual Figure Ground 8. Visual Form Constancy 9. Visual Closure 10. Binocularity 11.Visual Accommodation 12.Visual Saccades 12 Basic Processes are: 1. Vision The faculty or state of being able to see. The act or power of sensing with the eyes; sight. The Anatomy of Vision 6 stages in Development of the Vision system Birth to 4 months 4-6 months 6-8 months 8-12 months 1-2 years 2-3 years At birth babies can see patterns of light and dark.