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Scientist |
Division of Vision Science |
Toronto Western Research Institute,
TWH |
Scientist |
Hospital
For Sick Children Research Institute |
Staff Ophthalmologist |
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For Sick Children and Toronto Western Hospital
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The primary goal of my research is to understand neuroplasticity, the fundamental dynamic processes that allow the brain to adapt to inputs from, and changes in, the environment. I investigate neuroplasticity in the developing and mature visual system in normal and diseased states. I am particularly interested in understanding the brain mechanisms that cause abnormal eye movements, strabismus (eye misalignment), and amblyopia (lazy eye), as well as how to treat these diseases. My laboratories use a variety of techniques, including anatomic, behavioural, psychophysical, and neuroimaging methods, to investigate how the normal brain functions, and how these brain functions change in the diseased state. Current projects include:
- Crossed Eyes in Infancy (Infantile Esotropia) is a common health condition that affects one in 100-500 children. Contrary to the popular belief that crossed eyes is a purely cosmetic condition, children born with crossed eyes suffer from a number of visual and eye movement impairments. Our goal is to understand the brain mechanisms that cause crossed eyes and to find a cure for it. Specifically, our research aims to answer three major questions: (1) How do the brain circuits that control vision and eye movements differ between cross-eyed and visually-normal infants? (2) How can we alter the development of these brain circuits to prevent or cure crossed eyes in infancy? (3) Can early surgery prevent maldevelopment of these brain circuits?
- Lazy Eye (Amblyopia) is a visual impairment of one eye caused by inadequate use during early childhood. It is the most common cause of visual loss in one eye, and affects about 4% of the general population. Although tremendous resources are spent on preventing and treating lazy eye, many children with lazy eye continue to have abnormal vision throughout their adult lives. Our goal is to understand the brain mechanisms that cause lazy eye and to find a cure for it. Specifically, our research aims to answer four major questions: (1) How do the brain circuits in people with lazy eye differ from those with normal vision? (2) How does lazy eye affect three-dimensional (3D) depth perception and eye movements? (3) How do the eye-hand coordination skills in people with lazy eye differ from those with normal vision? (4) How can we develop more effective treatments for lazy eye?
- Double Vision (Diplopia) from Brain Diseases is a common and disabling feature of many diseases that affect adults, including strokes, brain tumours, diabetes, and multiple sclerosis. Our goal is to understand the brain mechanisms that cause double vision and to find a cure for it. Specifically, our research aims to answer three major questions: (1) How are the three-dimensional characteristics of eye movements altered by diseases of the brain? (2) What are the mechanisms underlying these changes, and how do they adapt over time? (3) What are the effects of different kinds of surgery on vision and on brain recovery / adaptation?
Fesharaki M, Karagiannis P, Tweed D, Sharpe JA, Wong AM. Adaptive neural mechanism for Listing’s law revealed in patients with skew deviation caused by brainstem or cerebellar lesion. Investigative Ophthalmology and Visual Science 2008;49:204-214.Sin L, Tychsen L, Foeller P, Bradley D, Wong AM. Early versus delayed correction of infantile strabismus in macaque monkeys: Effects on long-term eye alignment. Neuro-Ophthalmology 2007;31:167-169.
Richards M, Tychsen L, Foeller P, Bradley D, Wong AM. Early versus delayed correction of infantile strabismus in macaque monkeys: Effects on horizontal binocular connections in the striate cortex. Neuro-Ophthalmology 2007;31:171-174.
Niechwiej-Szwedo E, Gonzalez EG, Bahl B, Verrier MC, Wong AM, Steinbach MJ. Manipulation of extraocular muscle afference has no effect on higher order perceptual judgments. Vision Research 2007;47:3315-3323.
Kessler P, Tomlinson D, Blakeman A, Rutka J, Ranalli P, Wong AM. The high-frequency/acceleration head-heave test in detecting otolith diseases. Otology & Neurotology 2007;28:896-904.
Wong AM. An update on opsoclonus. Current Opinion in Neurology 2007;20:25-31.
Niechwiej-Szwedoa E, Gonzáleza E, Begae S, Verrier MC, Wong AM, Steinbach MJ. Proprioceptive role for palisade endings in extraocular muscles: Evidence from the Jendrassik Maneuver. Vision Research 2006;46:2268-2279.
Wong AM, McReelis K, Sharpe JA. Saccade dynamics in peripheral versus central sixth nerve palsies. Neurology 2006;66:1390-1398
Eizenman M, Sapir-Pichhadze R, Westall CA, Wong AM, Lee H, Morad Y. Eye movement responses to disparity vergence stimuli with artificial monocular scotomas. Current Eye Research 2006; 31:471-480.
Wong AM, Sharpe JA. Cerebellar skew deviation and the torsional vestibulo-ocular reflex. Neurology 2005;65:412-419.
Sharpe JA, McReelis K, Wong AM. Recovery of peripheral versus central nerves identified by saccadic velocity after abducens neuropathy. Annals of the New York Academy of Sciences 2005;1039: 417-429.
Wong AM, Burkhalter A, Tychsen L. Suppression of metabolic activity caused by infantile esotropia and strabismic amblyopia in striate visual cortex of macaque monkeys. Journal of the American Association for Pediatric Ophthalmology and Strabismus 2005;9:37-47.
Tychsen L, Wong AM, Burkhalter A. Paucity of horizontal connections for binocular vision in V1 of naturally-strabismic macaques: Cytochrome-oxidase compartment specificity. Journal of Comparative Neurology. 2004;474:261-275.
Muni RH, Wennberg R, Mikulis DJ, Wong AM. Bilateral horizontal gaze palsy in presumed paraneoplastic brainstem encephalitis associated with a benign ovarian teratoma. Journal of Neuro-Ophthalmology. 2004:24:114-118.
Tychsen L, Wong AM, Foeller P, Bradley D. Early versus delayed repair of infantile strabismus in macaque monkeys: II. Effects on motion visually evoked potentials. Investigative Ophthalmology and Visual Science 2004;45:821-827.
Wong AM, Foeller P, Bradley D, Burkhalter A, Tychsen L. Early versus delayed correction of infantile strabismus in macaque monkeys: I. Ocular motor effects. Journal of the American Association for Pediatric Ophthalmology and Strabismus 2003; 7:200-209.
