Eye Movements Do Not Affect Perceived Size
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Optical Illusions “What You See Is Not What You Get”
Optical Illusions “What you see is not what you get” The purpose of this lesson is to introduce students to basic principles of visual processing. Much of the lesson revolves around the use of visual illusions and interactive demonstrations with the students. The overarching theme of this lesson is that perception and sensation are not necessarily the same, and that optical illusions are a way for us to study the way that our visual system works. Furthermore, there are cells in the visual system that specifically respond to particular aspects of visual stimuli, and these cells can become fatigued. Grade Level: 3-12 Presentation time: 15-30 minutes, depending on which activities are chosen Lesson plan organization: Each lesson plan is divided into three sections: Introducing the lesson, Conducting the lesson, and Concluding the lesson. Each lesson has specific principles with associated figures, class discussion (D), and learning activities (A). This lesson plan is provided by the Neurobiology and Behavior Community Outreach Team at the University of Washington: http://students.washington.edu/watari/neuroscience/k12/LessonPlans.html 1 Materials: Computer to display some optical illusions (optional) Checkerboard illusion: Provided on page 8 or available online with explanation at http://web.mit.edu/persci/people/adelson/checkershadow_illusion.html Lilac chaser movie: http://www.scientificpsychic.com/graphics/ as an animated gif or http://www.michaelbach.de/ot/col_lilacChaser/index.html as Adobe Flash and including scientific explanation -
Pupil Responses Associated with Coloured Afterimages Are Mediated by the Magno-Cellular Pathway
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Aston Publications Explorer Vision Research 43 (2003) 1423–1432 www.elsevier.com/locate/visres Pupil responses associated with coloured afterimages are mediated by the magno-cellular pathway S. Tsujimura *, J.S. Wolffsohn, B. Gilmartin Neurosciences Research Institute, Aston University, Aston Triangle, Birmingham B4 7ET, UK Received 14 August 2002; received in revised form 27 January 2003 Abstract Sustained fixation of a bright coloured stimulus will, on extinction of the stimulus and continued steady fixation, induce an afterimage whose colour is complementary to that of the initial stimulus; an effect thought to be caused by fatigue of cones and/or of cone-opponent processes to different colours. However, to date, very little is known about the specific pathway that causes the coloured afterimage. Using isoluminant coloured stimuli recent studies have shown that pupil constriction is induced by onset and offset of the stimulus, the latter being attributed specifically to the subsequent emergence of the coloured afterimage. The aim of the study was to investigate how the offset pupillary constriction is generated in terms of input signals from discrete functional elements of the magno- and/or parvo-cellular pathways, which are known principally to convey, respectively, luminance and colour signals. Changes in pupil size were monitored continuously by digital analysis of an infra-red image of the pupil while observers viewed isoluminant green pulsed, ramped or luminance masked stimuli presented on a computer monitor. It was found that the amplitude of the offset pupillary constriction decreases when a pulsed stimulus is replaced by a temporally ramped stimulus and is eliminated by a luminance mask. -
Real Time Measurement and Processing of Pupillary Light Reflex for Early Detection of Disease
Journal of Computers Real Time Measurement and Processing of Pupillary Light Reflex for Early Detection of Disease Ippei Torii*, Takahito Niwa Aichi Institute of Technology, Dept. of Information Science, 1247 Yachigusa, Yakusa-cho, Toyota, Aichi, Japan. * Corresponding author. Tel.: 81-565-48-8121; email: mac[aitech.ac.jp Manuscript submitted January 10, 2019; accepted March 8, 2019. doi: 10.17706/jcp.14.3.161-169 Abstract: Recently, pupillary measurements have begun to be considered effective in the diagnosis of various physical conditions. Apart from optic neuropathy and retinal disorders, which are ocular diseases, diversions can be expected in the diagnosis of autonomic disturbance due to sympathetic and parasympathetic nerve disorders, cranial nerve disorders, cerebral infarction, depression, and diabetes. In this study, we have developed a real-time pupil diameter measuring system that is inexpensive and does not require a complicated device. When strong light is projected onto the eyeball, this system can measure the reaction time until the start of miosis, the time to achieve maximal miosis, and the difference in reaction speed of the left and right eyes. With this system, the status of a disease can be judged based on the distance from the threshold value. Key words: Real time measurement, eye movement, early detection of disease, image processing. 1. Introduction There are approximately one hundred million photoreceptor cells in the retina of human eyes. Light that shines on those cells is converted to nerve signals, which transmit the information to the brain, resulting in the visual recognition of objects. When light is radiated onto the eye, the pupillary light reflex is triggered, causing the pupillary diameter to decrease with a time delay of less than 1 sec. -
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. -
Conjunctive and Disjunctive Eye Movements an Pupillary Response Performance for Objective Metrics in Acute Mtbi
Conjunctive and Disjunctive Eye Movements an Pupillary Response Performance for Objective Metrics in Acute mTBI Carey Balaban, PhD1 Michael Hoffer, MD2 Mikaylo Sczczupak MD2 Alex Kiderman, PhD3 1University of Pittsburgh, 2 University of Miami, 3Neuro Kinetics, Inc. Disclosures • Michael E. Hoffer and Carey D. Balaban have no conflicts of interest or financial interests to report • Alexander Kiderman is an employee and shareholder of Neuro Kinetics, Inc. • The views expressed in this talk are those of the author(s) and do not necessarily reflect the official policy or position of the University of Pittsburgh, University of Miami, Department of the Navy, Department of Defense, or the U.S. Government. 2 Why is mTBI a Topic for Otolaryngology? • Balance disorders often present • Co-morbidities similar to balance-migraine- anxiety • Vestibular, oculomotor and reaction time tests provide objective metrics for acute mTBI Precision Medicine • Current clinical nosology as a clinical descriptive template – Symptoms – Signs – “Biomarkers” • Establish etiologic nosology – Identify acute response processes – Identify longitudinal processes – Plan interventions appropriate to patients’ clinical trajectories ‘Plain Language’ mTBI Definition • Documented traumatic event • ‘Not Quite Right’ (‘NQR’ criterion) • How does one quantify ‘NQR’? 5 Conjunctive Eye Movements as Objective mTBI Metrics: Up to 2 Weeks Post-Injury Conjuctive (Conjugate) Eye Movements for mTBI Diagnosis • High Frequency Horizontal Vestibulo-ocular Reflex – Computer-controlled Head Impulse Test (crHIT) • Saccades – Antisaccade Task – Predictive Saccade Task • Optokinetic Response • Smooth Pursuit Key Measure Changes Across Sessions Key Measure Changes Across Sessions Background • Disconjugate eye movements (convergence and divergence) track objects that vary in depth over the binocular visual field. These eye movements can be measured objectively and are commonly affected following mTBI. -
Exploring 3D Stereo with Incremental Rehearsal and Partial Occlusion to Instigate and Modulate Smooth Pursuit and Saccade Responses in Baseball Batting
Old Dominion University ODU Digital Commons Computational Modeling & Simulation Computational Modeling & Simulation Engineering Theses & Dissertations Engineering Summer 2016 Toward Simulation-Based Training Validation Protocols: Exploring 3d Stereo with Incremental Rehearsal and Partial Occlusion to Instigate and Modulate Smooth Pursuit and Saccade Responses in Baseball Batting Ricardo A. Roca Old Dominion University, [email protected] Follow this and additional works at: https://digitalcommons.odu.edu/msve_etds Part of the Engineering Commons Recommended Citation Roca, Ricardo A.. "Toward Simulation-Based Training Validation Protocols: Exploring 3d Stereo with Incremental Rehearsal and Partial Occlusion to Instigate and Modulate Smooth Pursuit and Saccade Responses in Baseball Batting" (2016). Doctor of Philosophy (PhD), Dissertation, Computational Modeling & Simulation Engineering, Old Dominion University, DOI: 10.25777/hvse-ts08 https://digitalcommons.odu.edu/msve_etds/3 This Dissertation is brought to you for free and open access by the Computational Modeling & Simulation Engineering at ODU Digital Commons. It has been accepted for inclusion in Computational Modeling & Simulation Engineering Theses & Dissertations by an authorized administrator of ODU Digital Commons. For more information, please contact [email protected]. TOWARD SIMULATION-BASED TRAINING VALIDATION PROTOCOLS: EXPLORING 3D STEREO WITH INCREMENTAL REHEARSHAL AND PARTIAL OCCLUSION TO INSTIGATE AND MODULATE SMOOTH PURSUIT AND SACCADE RESPONSES IN BASEBALL BATTING by Ricardo A. Roca B.S.E. May 1986, Tulane University M.S. January 2002, George Mason University A Dissertation Submitted to the Faculty of Old Dominion University in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY MODELING & SIMULATION OLD DOMINION UNIVERSITY August 2016 Approved by: Stacie I. Ringleb (Director) Michel A. Audette (Member) Lance M. -
Bridget Riley Valentine Op Art Heart
Op Art: Lesson Bridget Riley 6 Valentine Op Art Heart • How do 2D geometric shapes invoke movement? • How can the manipulation of geometric shapes and patterns create dimension in 2D art? LESSON OVERVIEW/OBJECTIVES Students will learn about the artist Bridget Riley and her work in Optical Art (Op Art). Riley (1931-present) is a British artist known for bringing about the Op Art movement. Op Art is a style of visual art that uses precise patterns and color to create optical illusions. Op art works are abstract, with many better known pieces created in black and white. Typically, they give the viewer the impression of movement, hidden images, flashing and vibrating patterns, or of swelling or warping. After learning about Bridget Rily and the Op Art movement, students will create an Op Art heart and background for Valentine’s Day. KEY IDEAS THAT CONNECT TO VISUAL ARTS CORE CURRICULUM: Based on Utah State Visual Arts Core Curriculum Requirements (3rd Grade) Strand: CREATE (3.V.CR.) Students will generate artistic work by conceptualizing, organizing, and completing their artistic ideas. They will refine original work through persistence, reflection, and evaluation. Standard 3.V.CR.1: Elaborate on an imaginative idea and apply knowledge of available resources, tools, and technologies to investigate personal ideas through the art-making process. Standard 3.V.CR.2: Create a personally satisfying artwork using a variety of artistic processes and materials. Standard 3.V.CR.3: Demonstrate an understanding of the safe and proficient use of materials, tools and equipment for a variety of artistic processes. -
Care of the Patient with Accommodative and Vergence Dysfunction
OPTOMETRIC CLINICAL PRACTICE GUIDELINE Care of the Patient with Accommodative and Vergence Dysfunction OPTOMETRY: THE PRIMARY EYE CARE PROFESSION Doctors of optometry are independent primary health care providers who examine, diagnose, treat, and manage diseases and disorders of the visual system, the eye, and associated structures as well as diagnose related systemic conditions. Optometrists provide more than two-thirds of the primary eye care services in the United States. They are more widely distributed geographically than other eye care providers and are readily accessible for the delivery of eye and vision care services. There are approximately 36,000 full-time-equivalent doctors of optometry currently in practice in the United States. Optometrists practice in more than 6,500 communities across the United States, serving as the sole primary eye care providers in more than 3,500 communities. The mission of the profession of optometry is to fulfill the vision and eye care needs of the public through clinical care, research, and education, all of which enhance the quality of life. OPTOMETRIC CLINICAL PRACTICE GUIDELINE CARE OF THE PATIENT WITH ACCOMMODATIVE AND VERGENCE DYSFUNCTION Reference Guide for Clinicians Prepared by the American Optometric Association Consensus Panel on Care of the Patient with Accommodative and Vergence Dysfunction: Jeffrey S. Cooper, M.S., O.D., Principal Author Carole R. Burns, O.D. Susan A. Cotter, O.D. Kent M. Daum, O.D., Ph.D. John R. Griffin, M.S., O.D. Mitchell M. Scheiman, O.D. Revised by: Jeffrey S. Cooper, M.S., O.D. December 2010 Reviewed by the AOA Clinical Guidelines Coordinating Committee: David A. -
A Single Coordinate Framework for Optic Flow and Binocular Disparity
A coordinate framework for optic flow and disparity Glennerster and Read A single coordinate framework for optic flow and binocular disparity 1¶* 2¶ Andrew Glennerster and Jenny C.A. Read 1 School of Psychology and Clinical Language Sciences, University of Reading, Reading RG6 6AL 2 Institute of Neuroscience, Newcastle University, NE2 4HH ¶ These authors contributed equally to this work. * Corresponding author. Email [email protected] (AG) A coordinate framework for optic flow and disparity Glennerster and Read Abstract Optic flow is two dimensional, but no special qualities are attached to one or other of these dimensions. For binocular disparity, on the other hand, the terms 'horizontal' and 'vertical' disparities are commonly used. This is odd, since binocular disparity and optic flow describe essentially the same thing. The difference is that, generally, people tend to fixate relatively close to the direction of heading as they move, meaning that fixation is close to the optic flow epipole, whereas, for binocular vision, fixation is close to the head-centric midline, i.e. approximately 90 degrees from the binocular epipole. For fixating animals, some separations of flow may lead to simple algorithms for the judgement of surface structure and the control of action. We consider the following canonical flow patterns that sum to produce overall flow: (i) ‘towards’ flow, the component of translational flow produced by approaching (or retreating from) the fixated object, which produces pure radial flow on the retina; (ii) ‘sideways’ flow, the remaining component of translational flow, which is produced by translation of the optic centre orthogonal to the cyclopean line of sight and (iii) ‘vergence’ flow, rotational flow produced by a counter-rotation of the eye in order to maintain fixation. -
Handbook of EEG INTERPRETATION This Page Intentionally Left Blank Handbook of EEG INTERPRETATION
Handbook of EEG INTERPRETATION This page intentionally left blank Handbook of EEG INTERPRETATION William O. Tatum, IV, DO Section Chief, Department of Neurology, Tampa General Hospital Clinical Professor, Department of Neurology, University of South Florida Tampa, Florida Aatif M. Husain, MD Associate Professor, Department of Medicine (Neurology), Duke University Medical Center Director, Neurodiagnostic Center, Veterans Affairs Medical Center Durham, North Carolina Selim R. Benbadis, MD Director, Comprehensive Epilepsy Program, Tampa General Hospital Professor, Departments of Neurology and Neurosurgery, University of South Florida Tampa, Florida Peter W. Kaplan, MB, FRCP Director, Epilepsy and EEG, Johns Hopkins Bayview Medical Center Professor, Department of Neurology, Johns Hopkins University School of Medicine Baltimore, Maryland Acquisitions Editor: R. Craig Percy Developmental Editor: Richard Johnson Cover Designer: Steve Pisano Indexer: Joann Woy Compositor: Patricia Wallenburg Printer: Victor Graphics Visit our website at www.demosmedpub.com © 2008 Demos Medical Publishing, LLC. All rights reserved. This book is pro- tected by copyright. No part of it may be reproduced, stored in a retrieval sys- tem, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Library of Congress Cataloging-in-Publication Data Handbook of EEG interpretation / William O. Tatum IV ... [et al.]. p. ; cm. Includes bibliographical references and index. ISBN-13: 978-1-933864-11-2 (pbk. : alk. paper) ISBN-10: 1-933864-11-7 (pbk. : alk. paper) 1. Electroencephalography—Handbooks, manuals, etc. I. Tatum, William O. [DNLM: 1. Electroencephalography—methods—Handbooks. WL 39 H23657 2007] RC386.6.E43H36 2007 616.8'047547—dc22 2007022376 Medicine is an ever-changing science undergoing continual development. -
Do You Really Need Your Oblique Muscles? Adaptations and Exaptations
SPECIAL ARTICLE Do You Really Need Your Oblique Muscles? Adaptations and Exaptations Michael C. Brodsky, MD Background: Primitive adaptations in lateral-eyed ani- facilitate stereoscopic perception in the pitch plane. It also mals have programmed the oblique muscles to counter- recruits the oblique muscles to generate cycloversional rotate the eyes during pitch and roll. In humans, these saccades that preset torsional eye position immediately torsional movements are rudimentary. preceding volitional head tilt, permitting instantaneous nonstereoscopic tilt perception in the roll plane. Purpose: To determine whether the human oblique muscles are vestigial. Conclusions: The evolution of frontal binocular vision has exapted the human oblique muscles for stereo- Methods: Review of primitive oblique muscle adapta- scopic detection of slant in the pitch plane and nonste- tions and exaptations in human binocular vision. reoscopic detection of tilt in the roll plane. These exap- tations do not erase more primitive adaptations, which Results: Primitive adaptations in human oblique muscle can resurface when congenital strabismus and neuro- function produce rudimentary torsional eye move- logic disease produce evolutionary reversion from exap- ments that can be measured as cycloversion and cyclo- tation to adaptation. vergence under experimental conditions. The human tor- sional regulatory system suppresses these primitive adaptations and exaptively modulates cyclovergence to Arch Ophthalmol. 2002;120:820-828 HE HUMAN extraocular static counterroll led Jampel9 to con- muscles have evolved to clude that the primary role of the oblique meet the needs of a dy- muscles in humans is to prevent torsion. namic, 3-dimensional vi- So the question is whether the human ob- sual world. -
The Effect of Eye Movements and Blinks on Afterimage Appearance and Duration
Journal of Vision (2015) 15(3):20, 1–15 http://www.journalofvision.org/content/15/3/20 1 The effect of eye movements and blinks on afterimage appearance and duration School of Psychology, Cardiff University, # Georgina Powell Cardiff, Wales, UK $ School of Psychology, Cardiff University, # Petroc Sumner Cardiff, Wales, UK $ Lyon Neuroscience Research Center, # Aline Bompas Centre Hospitalier Vinatier, Bron, Cedex, France $ The question of whether eye movements influence argued that afterimage signals are inherently ambigu- afterimage perception has been asked since the 18th ous, and this could explain why their visibility is century, and yet there is surprisingly little consensus on influenced by cues, such as surrounding luminance how robust these effects are and why they occur. The edges, more than are real stimuli (Powell, Bompas, & number of historical theories aiming to explain the Sumner, 2012). Helmholtz (1962) identified another cue effects are more numerous than clear experimental that is important to take into account when conducting demonstrations of such effects. We provide a clearer afterimage experiments: characterization of when eye movements and blinks do or do not affect afterimages with the aim to distinguish For obtaining really beautiful positive after- between historical theories and integrate them with a images, the following additional rules should be modern understanding of perception. We found neither saccades nor pursuit reduced strong afterimage observed. Both before and after they are devel- duration, and blinks actually increased afterimage oped, any movement of the eye or any sudden duration when tested in the light. However, for weak movement of the body must be carefully avoided, afterimages, we found saccades reduced duration, and because under such circumstances they invariably blinks and pursuit eye movements did not.