The New England Journal of Medicine

Fixing My Gaze: A Scientist’s Journey into Seeing in Three Dimensions

By Susan R. Barry. 249 pp., illustrated. New York, Basic Books,2009. $26. ISBN 978-0-465-00913-8.

Seeing the three-dimensional world with two-dimensional retinas presents the brain with two problems. To locate an object in space requires depth perception, which can be acquired from one eye alone through size, perspective, and motion parallax. Stereopsis is an entirely different quality that gives the world dimensionality; it requires binocular vision. Strabismus is the main reason for disrupted stereopsis, although binocular vision fails to develop in a few ostensibly normal persons. This book is about what people with disrupted stereopsis are missing and how the condition can be remedied even late in life.

Susan Barry crafts a story from her personal experience with strabismus, and she uses the advantage of her background as a neuroscientist to weave well-referenced explanations of binocular vision, amblyopia, optical illusions, visual styles, the history of stereoscopic vision and the Victorian stereoscope craze, and David Hubel and Torsten Wiesel’s discovery of the specificity of occipital neurons.

Until special exercises allowed her to fuse images and see stereoscopically, Barry was a denizen of a world like that created by Edwin Abbott in his 1884 satirical novella, Flatland: A Romance of Many Dimensions — she could not even conceptualize binocular vision. One axis of her book is a graceful and grateful appreciation of=2 0a newly acquired “ability to see the volume of space between objects and to see each object as occupying its own space” — revelations that allowed her to live “among” and “in” the things of this world and gave her first moments of snow falling, trees branching, and a faucet arcing out of the sink. Even her adult sentiment did not prevent her response from being natural and childlike, perhaps similar to our response to a first peek at the leaping vitality of figures in a View-Master (a successor to the handheld stereograph viewer popularized in the 19th century by Oliver Wendell Holmes).

Capitalizing probably more on latent neuronal connections than on the creation of new ones, Barry benefited from orthoptics — a hidden corner of restorative medicine. With contrived ocular exercises, specially trained and imaginative optometrists treat patients whose eyes are cosmetically aligned but imperfectly foveated. The simplicity of the exercises and of the apparatus (such as beads on a string, papers taped to walls, and strips of film) is bracing for a profession enamored with technology.
The book’s main contribution, however, is exposing the wrong-headed dogma that acuity and binocular vision can be restored only during a critical developmental period. Surgical correction of strabismus is dominated by this notion, first posited by Claud Worth in his landmark 1903 book, Squint: Its Causes, Pathology, and Treatment,and set at a hard stop at 2 years of age by his student Francis Chavasse. The experiments of Hubel and Wiesel are often cited as confirming the lost malleability of the adult brain, but Barry points out that they did no such thing because there was no attempt at restoration of fusion. Her experiences and those she recounts from others belie the “nothing else can be done” message that ophthalmologists gave to her and to her mother throughout her childhood. Several visual scientists have now demonstrated the reversibility of infantile loss of vision and stereopsis, but blindness to these findings and underappreciation of the solutions offered by orthoptics still persist.

We do not understand the biologic changes that correspond to neurological improvement, any more than we can put ourselves in Barry’s position simply by covering one eye. The annoyingly overused term “plasticity” gets in the way of this and similar expositions of the brain. In the meantime, we might heed Barry by rediscovering the visual pleasures of sculpture, architecture, and the Grand Canyon.

Allan H. Ropper, M.D.Brigham and Women’s Hospital Boston, MA 02115N Engl J Med 361;1 July 2, 2009

Larry Fitzgerald – The NFL’s most exciting receiver

Read how Arizona Cardinal’s Larry Fitzgerald benefitted from eye exercises as a boy

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National Eye Institute releases press release:

More Effective Treatment Identified for Common Childhood Vision Disorder

Read more click here

Clinical Trial shows positive results

Randomized Clinical Trial of Treatments for Symptomatic Convergence Insufficiency in Children

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Blog talks about Vision Therapy and related information

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Patient Newsletter

Professional Newsletter

Dear Abby Column published on April 17, 2007


DEAR ABBY: Please help me get the word out about a common condition that severely affects children’s ability to succeed in school because it inhibits reading, spelling and concentration.
My daughter, who was obviously bright, tested at first-grade reading level in fifth grade. She had undergone all the school testing for learning disabilities, plus two days of testing at a respected university hospital. None of these tests or specialists revealed what could be wrong with her.

My child’s self-esteem suffered. Her confidence faltered; she began acting out in school. At home she was a great kid, until it came time for schoolwork. Then the battles began. She thought she was dumb. When studying, she could read for only a very short time. She often begged me to read things to her. When working on spelling and assigned to rewrite the words she missed five times, she often recopied them wrong. We thought she just wasn’t trying.

After much research on the Internet, I came across a disorder called “convergence insufficiency disorder.” This visual condition is the leading cause of eyestrain. Fortunately, we had the opportunity to have her tested at the Mayo Clinic, where her condition was confirmed, and she was successfully treated with vision therapy.

It was as though a miracle had occurred. After six months of treatment, my daughter is almost at her age-appropriate reading level. Her comprehension and retention have markedly increased, and her self-esteem and attitude about reading are much better.

Children with this condition will not benefit from tutoring, special education or extra help from teachers until the condition is diagnosed and treated. My child had 20/20 vision and still had this disorder. It’s not routinely checked with eye exams, and schools don’t test for it.

I suspect that many children out there are undiagnosed or misdiagnosed and going untreated. The treatment for convergence insufficiency disorder is noninvasive, effective, and much of it can be done at home. Please help me get the word out so other families won’t have to go through what we experienced. — ANGIE W. IN MINNESOTA

DEAR ANGIE: I am pleased to help you get the word out to other families whose children are struggling to learn. After reading your letter, I contacted my experts at the Mayo Clinic in Rochester, Minn., and was informed that this problem, where the eyes drift too much inward (or outward) in attempting to focus, can also be present in adults.

The symptoms can include eyestrain, headaches, blurred vision, sleepiness and trouble retaining information when reading. Other symptoms associated with convergence insufficiency include a “pulling” sensation around the eyes, the rubbing or closing of one eye when reading, words seeming to “jump” or “float” across the page, needing to reread the same line of words, frequent loss of place, general inability to concentrate and short attention span.

The good news is: Vision exercises can fix the problem in most cases, some done at home and some performed in-office with a vision therapist. Prism glasses are another option; however, they are more often prescribed for adults with this disorder than for children.

Dear Abby is written by Abigail Van Buren, also known as Jeanne Phillips, and was founded by her mother, Pauline Phillips. Write Dear Abby at or P.O. Box 69440, Los Angeles, CA 90069.

Children’s Vision Bill Introduced in House

The Vision Care for Kids Act of 2007 was introduced January 17 in the U.S. House of Representatives. This legislation is intended to make the fight against undiagnosed and untreated vision problems in school-age children a national priority. Read more.

The website has an excellent article titled “20/20 is Not Enough” which urges parents to have their children’s vision evaluated by a developmental optometrist, particularly if they are having learning difficulties.

The articles author, Fran Santoro Hamilton, relates how her son’s vision problem was identified by his teacher and helped with vision therapy. You will want to share this story with parents and teachers. To view and print a copy, go to

The Mankato (MN) Free Press ran an extensive article on Vision Therapy services provided through the offices of Dr. Lori Mowbray, COVD Fellow. Cited in the article was Ms. Gerri Struss, COVT, who along with Nancy Beran, Teresa Krohn and Kim Thompson, coordinates vision therapy services for the Mankato Vision Therapy Center.

The article discusses how vision therapy improved the reading ability for one of the centers patients as well as background information on what vision therapy is and how it works. To read the entire article go to:

Listen to the very interesting interview of Sue Barry,
Oliver Sacks, and David Hubel (Nobel Prize Laureate, Physiology and
Medicine) on the Morning Edition of National Public Radio, Monday, June 26.
See on

The program told the inspiring story of Sue Barry who gained two-eyed
vision and 3D stereo vision as a result of vision therapy.