Identification and treatment of the visual processing asymmetry in MS patients with optic neuritis: The Pulfrich phenomenon

Millad J Sobhanian; Rohit Agarwal; Ethan Meltzer; Eric Kildebeck; Benjamin S Frohman; Ashley N Frohman; Steven L Galetta; Shiv Saidha; Owen White; Pablo Villoslada; Friedemann Paul; Axel Petzold; Robert L Rennaker; Elena H Martinez-Lapiscina; Laura J Balcer; Randy Kardon; Elliot M Frohman; Teresa C Frohman

doi:10.1016/j.jns.2018.01.029

Identification and treatment of the visual processing asymmetry in MS patients with optic neuritis: The Pulfrich phenomenon

J Neurol Sci. 2018 Apr 15:387:60-69. doi: 10.1016/j.jns.2018.01.029. Epub 2018 Feb 3.

Authors

Millad J Sobhanian¹, Rohit Agarwal¹, Ethan Meltzer², Eric Kildebeck³, Benjamin S Frohman¹, Ashley N Frohman¹, Steven L Galetta⁴, Shiv Saidha⁵, Owen White⁶, Pablo Villoslada⁷, Friedemann Paul⁸, Axel Petzold⁹, Robert L Rennaker¹⁰, Elena H Martinez-Lapiscina¹¹, Laura J Balcer⁴, Randy Kardon¹², Elliot M Frohman¹³, Teresa C Frohman¹⁴

Affiliations

¹ Department of Neurology, Dell Medical School, University of Texas at Austin, TX, USA.
² Partner's Neurology Residency Training Program, Massachusettes General & Brigham & Women's Hospitals, Harvard Medical School, Cambridge, MA, USA.
³ Department of Neurology, Dell Medical School, University of Texas at Austin, TX, USA; The Center for Engineering Innovation, University of Texas at Dallas, Richardson, TX, USA.
⁴ The Department of Neurology, Population Health, New York University School of Medicine, New York, NY, USA; The Department of Ophthalmology, New York University School of Medicine, New York, NY, USA.
⁵ The Department of Neurology, Johns Hopkins Hospital, Baltimore, MD, USA.
⁶ Department of Neurology, Royal Melbourne Hospital, Parkville, Australia; Department of Medicine, University of Melbourne, Parkville, Australia.
⁷ Institut d'Investigacions Biomediques August Pi Sunyer (IDIBAPS), Barcelona, Spain; University of California at San Francisco, USA.
⁸ NeuroCure Clinical Research Center and Clinical and Experimental, Multiple Sclerosis Research Center, Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany; Experimental and Clinical Research Center, Max Delbrueck Center for Molecular Medicine, Charité Universitätsmedizin Berlin, Berlin, Germany.
⁹ Moorfields Eye Hospital, City Road, London, UK; The National Hospital for Neurology and Neurosurgery, UCL Institute of Neurology, Queen Square, London, UK; Neuro-ophthalmology Expertise Centre VUmc, Amsterdam, Netherlands.
¹⁰ School of Biomedical Engineering, University of Texas at Dallas, Richardson, TX, USA; Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, USA.
¹¹ Institut d'Investigacions Biomediques August Pi Sunyer (IDIBAPS), Barcelona, Spain.
¹² Department of Ophthalmology, University of Iowa, USA; Center for Prevention and Treatment of Visual Loss, Iowa City, IA, USA.
¹³ Department of Neurology, Dell Medical School, University of Texas at Austin, TX, USA; School of Biomedical Engineering, University of Texas at Dallas, Richardson, TX, USA; Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, USA.
¹⁴ Department of Neurology, Dell Medical School, University of Texas at Austin, TX, USA; School of Biomedical Engineering, University of Texas at Dallas, Richardson, TX, USA; Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, USA. Electronic address: teresa.frohman@austin.utexas.edu.

PMID: 29571874
DOI: 10.1016/j.jns.2018.01.029

Abstract

Background: The Pulfrich phenomenon (PF) is the illusory perception that an object moving linearly along a 2-D plane appears to instead follow an elliptical 3-D trajectory, a consequence of inter-eye asymmetry in the timing of visual object identification in the visual cortex; with optic neuritis as a common etiology.

Objective: We have designed an objective method to identify the presence and magnitude of the PF, in conjunction with a cooresponding strategy by which to abolish the effect; with monocular application of neutral density filters to the less affected fellow eye, in patients with MS and a history of optic neuropathy (e.g. related to acute optic neuritis or subclinical optic neuropathy).

Methods: Twenty-three MS patients with a history of acute unilateral or bilateral optic neuritis, and ten healthy control subjects (HC) were recruited to participate in a pilot study to assess our strategy. Subjects were asked to indicate whether a linearly moving pendulum ball followed a linear 2-D path versus an illusory 3-D elliptical object-motion trajectory, by reporting the ball's approximation to one of nine horizontally-oriented colored wires that were positioned parallel to one another and horizontal to the linear pendulum path. Perceived motion of the bob that moved along wires behind or in front (along the 'Z' plane) of the middle reference wire indicated an illusory elliptical trajectory of ball motion consistent with the PF.

Results: When the neutral density filter titration was applied to the fellow eye the severity of the PF decreased, eventually being fully abolished in all but one patient. The magnitude of neutral density filtering required correlated to the severity of the patient's initial PF magnitude (p < 0.001).

Conclusions: We ascertained the magnitude of the visual illusion associated with the PF, and the corresponding magnitude of neutral density filtering necessary to abolish it.

Keywords: Asymmetric visual transmission; Neutral density filter; Pulfrich phenomenon; Visual illusion.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Female
Flicker Fusion / physiology
Humans
Illusions / physiology*
Male
Middle Aged
Motion Perception / physiology*
Multiple Sclerosis / complications*
Optic Neuritis* / complications
Optic Neuritis* / diagnosis
Optic Neuritis* / therapy
Photic Stimulation
Tomography, Optical Coherence
Visual Acuity / physiology
Young Adult