Saturday, August 8, 2009

Binocular motor coordination during saccades and fixations while reading: A magnitude and time analysis

Reading involves saccades and fixations. Misalignment of the eyes should be small enough to allow sensory fusion. Recent studies reported disparity of the eyes during fixations. This study examines disconjugacy, i.e. change in disparity over time, both during saccades and fixations. Text reading saccades and saccades to single targets of similar sizes (2.5-) are compared. Young subjects were screened to avoid problems of binocular vision and oculomotor vergence. The results show high quality of motor binocular coordination in both tasks: the amplitude difference between the saccade of the eyes was approximately 0.16-; during the fixation period, the drift difference was only 0.13-. The disconjugate drift occurred mainly during the first 48 ms of fixation, was equally distributed to the eyes and was often reducing the saccade disconjugacy. Quality of coordination regardless of the task is indicative of robust physiological mechanisms. We suggest the existence of active binocular control mechanisms in which vergence signals may have a central role. Even computation of saccades may be based on continuous interaction between saccade and vergence.

Friday, August 7, 2009

All children should have eye exam by age 3

...Next to Christmas, the summer holidays are a very exciting time in a child's life. The end of the school year marks the beginning of two months of no school books! Parents are usually busy planning summer camps and family vacations.It's also a perfect time to have your children's eyes examined by an optometrist in preparation for the beginning of the school year in September.By the age of three, all children should have a thorough eye examination. Most optometrists prefer to see children by 12 months of age for their first eye exam....

Children and Vision Video

Thursday, August 6, 2009

Eye strain comments...

A reader left this comment:

... has left a new comment on your post "Eye strain and convergence insufficiency":

This article raises a very good point. If anyone is suffering from symptoms of Computer Eye Strain or general eye strain, they should get evaluated by a Behavioral Optometrist who can test for such muscle imbalances as "convergence insufficiency", and give eye exercises to help with this problem. To locate a practitioner near you, go to

Question about CI and ADHD

A question from a reader:

Anonymous has left a new comment on your post "What is ADHD (Attention

Deficit Hyperactivity Diso...":

My 9 year old son has many vision issues caused from severe prematurity; ROP, Convergence Insufficiency, misalignment, strabismus, etc. His vision issues can be helped with VT, but not completely resolved because of the severity. Our developmental pediatrician reccomends that we try “strattera” for possible ADHD. Mainly attention and mild impulse issues—NOT hyperactivity. Are you saying that vision issues, such as my sons, often look like ADHD symptoms--- but the symptoms are completely caused by the vision issues, not ADHD?

Comments: What the research shows is that a good number of children who have convergence problems have attentional problems and that many children with attentional problems have convergence problems. The ADHD symptoms can be caused by many factors....what I'm saying is don't over look the role vision may play... DM

Vision, learning screening could save young eyes

Children's vision could affect their work in the classroom.Local vision clinic, Stars in Your Eyes Vision Training Center, is offering free vision and learning screenings to help parents detect possible hindrances to their child's learning.The special screening is about five extra minutes tacked on to a traditional eye exam that can make a world of difference for children. ...It's almost back-to-school and time for routine health checkups. ... News8Video

Topiramate Induced Acute Angle Closure Glaucoma

...Topiramate is an oral sulphamate medication primarily used for seizure, migraine and neuropathic pain. It has been associated with secondary angle closure, which can mimic acute angle closure glaucoma. Suspicion for medication induced angle closure glaucoma should be higher whenever angle closure presents bilaterally. We present two cases of bilateral angle closure glaucoma secondary to topiramate....

Comments: It seems as if 80% of my special needs patients are on Topirmate. Watch for increased IOP. DM

Ophthalmic findings in dyslexic schoolchildren

...The most conspicuous common denominator in those with dyslexia was revealed to be the convergence insufficiency type of exodeviation, occurring in 38% of the general deficiency dyslexic subgroup and in 36% ofthe visuomotor dyslexic subgroup. This finding suggests a low accommodative convergence/accommodation ratio in these children....

Comments: Children with dyslexia have a high incidence of convergence insufficiency according to this British Journal of Ophthalmology article. DM


By C. E. Davies, M.D.

THE interesting part of the practice of ophthalmology is not confined to the operating
room, where the surgeon extracts a lens or secures a transplant, but is also very often
found in the refraction room, where judgment and experience are so important to the comfort
of the patient. This is particularly applicable in the case of convergence insufficiency....

Comments: More than 50 years ago, OMDs thought treating convergence insufficiency non-surgically was a good idea. What happened? DM

Eye strain and convergence insufficiency

Eye strain and headache are common ocular symptoms,
and the main cause in persons aged 15 to 40 is convergence
insufficiency. It is more common in females than in males.
Many patients are supplied with glasses for eye strain
without the causative convergence insufficiency being
treated. The treatment in most cases is orthoptic exercises.

Comment: This article was written more than 30 years ago in the British Medical Journal.....why won't all of our OMD colleagues accept this? Even then it was known that orthoptics (aka optometric vision therapy) was the treatment of choice. DM

Make Eye Exams Part of the Back to School Routine

...Children across the country are gearing up for a new school year. Before heading back to the classroom, the American Optometric Association (AOA) recommends a visit to the optometrist. Healthy vision is an important part to the learning process and success in school. Reading, writing and computer work are among the visual skills that students are required to perform daily. However, studies show that 86 percent of children start school without ever having an eye examination.....

Comments: With all this talk about health care...we can't even seem to afford appropriate eye care for our country's children. Talk about having our priorities screwed up! DM

Neuroscientist discusses how optometric vision therapy helped her to develop stereovision.

From AOAs First Look:

Neuroscientist discusses how optometric vision therapy helped her to develop stereovision.

In Scientific American (8/4), Mind Matters editor Jonah Lehrer intervie wed neuroscientist Sue Barry, "the author of the newly released book, Fixing My Gaze, which tells the story of how Barry, at the age of 48, finally learned to see in 3-D." Barry, who had "been cross-eyed since early infancy," had undergone "three childhood surgeries" that "made [her] eyes look normal." Only in college did she realize that she was unable to "see in 3-D." In her late forties, Barry "consulted a developmental optometrist who prescribed...a program of optometric vision therapy designed to stabilize [her] gaze," while providing her "with the feedback" she "needed to know where in space each eye was looking. With this feedback," she "learned to aim the two eyes at the same location in space at the same time," thus being able "to see in 3D. Further therapy taught" her "how to integrate" the "new 3D views with" her "former ways of judging depth and distance." As a result of vision therapy, "these changes became automatic," and Barry no longer suffers from stereoblindness.

Signs of Vision Problems in Children Video

ABC News Presents: COVDer, Dr. Carol Hong in the news!

The five most common signs that your child may have a vision problem.

The five most common signs that a vision problem may be interfering with your child's ability to read and learn are:

  1. Skips lines, rereads lines

  2. Poor reading comprehension

  3. Takes much longer doing homework than it should take

  4. Reverses letters like B's into D's when reading

  5. Has a short attention span with reading and schoolwork

Dr. Carole Hong is Board certified in vision development and vision therapy who diagnosis and treats vision problem that interfere with reading, learning and 3D/stereo vision, and practices in san Carlos, California. She holds the office of Vice-President for the COVD, College of Optometrists in Vision Development.

The College of Optometrists in Vision Development (COVD) is an international, non-profit optometric membership organization that provides education, evaluation and board certification programs in behavioral and developmental vision care, vision therapy and visual rehabilitation.

3D Vision Workshopt with Susan Barry, PhD Video Part 1

3D Workshop with Susan Barry, PhD Video Part 2

Susan Barry, PhD:Fixing My Gaze Part 2

Susan Barry, PhD: Fixing My Gaze Vide part 3

Susan Barry, PhD: Fixing My Gaze VideoSusan Barry, PhD:Fixing My Gaze Video

Eccentric Circles Training Video

20/20 is not enough! VT news story

Vision Therapy for Special Needs Patient


...We report an apparent three-fold greater incidence of ADHD among patients with CI when compared with the incidence of ADHD in the general US population. We also note a seeming three-fold greater incidence of CI in the ADHD population. ...patients diagnosed with ADHD should be evaluated to identify the ...subset that may have CI -- a condition that responds [best] to treatment [in the office and at home].

Comments: Although I mentioned this study's worth mentioning again and goes well with the study I noted just prior to this post. Please note I added [comments] supported by current research above. DM

Nearpoint phorias after nearwork predict ADHD symptoms in college students.

...Phorias postnearwork, but not prenearwork, predicted self-reported ADHD-related symptoms in college students. These results link binocular imbalance immediately after sustained nearwork to symptoms theorized to result from nearwork-induced visual stress....

Comments: The evidence continues to mount that vision system function and behaviors related to ADHD are closely associated. DM

Medicines Top Cause of Poisoning in Kids

...Children are twice as likely to be poisoned by the medicine cabinet than by cleaning products or other household substances, researchers found....Emergency department visits for unintentional poisoning involved prescription or over-the-counter medication in 68.9% of pediatric cases...

Difference in binocular rivalry rate between patients with bipolar I and bipolar II disorders

...The present results reveal a significant difference in the mean phase duration of binocular rivalry between subjects with BD-I and those with BD-II, suggesting the presence of some neurobiological difference between these two subtypes of bipolar disorder....

Prevalence and Causes of Visual Impairment in African-American and Hispanic Preschool Children: The Multi-Ethnic Pediatric Eye Disease Study

...More than 5% of African-American and Hispanic preschool children in Los Angeles County have either correctable visual impairment from uncorrected refractive error or visual impairment from amblyopia related to refractive error....

Comments:This means that there are thousands....maybe tens of thousands of children who need optometric vision care. This also means that if all had participated in the AOA's InfantSee program, most would not be amblyopic now. Dear ophthalmology colleagues, are you now convinced that full pediatric eye examinations should be required for each and every child? It seems like the vision screenings most of these children participated in at school...missed the problems! How sad and unfortunate for these children and their families. DM

Neurobiological Approaches on Brains of Children with Dyslexia: Review

...Learning difficulties commonly comprise a heterogeneous group of disorders manifested by unexpected problems in some children's experiences in the academic performance arena. ...The aim of this review is to explain the postmortem, structural or functional neuroimaging, and electrophysiological studies of human brains in children. The findings about these neuropathological and neurofunctional characteristics of developmental dyslexia, prospective studies beginning early in the life span and studies targeting remedial intervention will help to set the research agendas for future studies to follow....

Rhythm Reproduction in Kindergarten, Reading Performance at Second Grade, and Developmental Dyslexia Theories

...Temporal processing deficit could be associated with a specific difficulty in learning to read. In 1951, Stambak provided preliminary evidence that children with dyslexia performed less well than good readers in reproduction of 21 rhythmic patterns. Stambak's task was administered to 1,028 French children aged 5-6 years. The score distribution (from 0 to 21) was quasi-normal, with some children failing completely and other performing perfectly. In second grade, reading was assessed in 695 of these children. Kindergarten variables explained 26% of the variance of the reading score at second grade. The Stambak score was strongly and linearly related to reading performance in second grade, after partialling out performance on other tasks (oral repetition, attention, and visuo-spatial tasks) and socio-cultural level. Findings are discussed in relation to perceptual, cerebellar, intermodal, and attention-related theories of developmental dyslexia. It is concluded that simple rhythm reproduction tasks in kindergarten are predictive of later reading performance....

Medically unexplained visual symptoms in children and adolescents: an indicator of abuse or adversity?

...Two young adults and one child (all female) are described with medically unexplained impaired vision and diplopia, which on further investigation were found to be associated with abuse or adversity, and in one case was followed by the development of further unexplained symptoms....

Wednesday, August 5, 2009

SOVOTO the Vision Therapy Connection

If you are a doctor, therapist, parent, or patient .... you may find this site useful in understanding more about vision therapy. DM

School Relagted Vision Problems Video

What Is Concussion? What Is Mild Traumatic Brain Injury (MTBI)?

Concussion is also known as mild brain injury, mild traumatic brain injury (MTBI), mild head injury and minor head trauma. Some experts define concussion as a head injury with temporary loss of brain function, which can cause cognitive, physical and emotional symptoms. Concussion may also be defined as an injury to the brain generally caused by a jolt or blow to the head - in the majority of cases the individual does not lose consciousness. ...

Comments: Even mild brain injury can have lasting eye and vision problems long after the obvious problems have been attended to....go to to find a doctor who can help. Also go to for a whole Optometry & Vision Development theme issue on traumatic brain injury. DM

ADHD in School Video for Parents

Comments: good video over all....but once again they fail to talk about the role vision plays in ADHD. DM

Neurological Differences Support Dyslexia Subtypes

...Parts of the right hemisphere of the brains of people with dyslexia have been shown to differ from those of normal readers. Researchers writing in the open access journal BMC Neuroscience used magnetic resonance imaging (MRI) to compare the two groups, and were able to associate the neurological differences found with different language difficulties within the dyslexic group....

What is ADHD (Attention Deficit Hyperactivity Disorder)?

Health experts say that ADHD (attention deficit hyperactivity disorder) is the most common behavioral disorder that starts during childhood. However, it does not only affect children - people of all ages can suffer from ADHD. Psychiatrists say ADHD is a neurobehavioral developmental disorder....

Comments: This is a nice review of ADHD and for the most part has correct information. It does not mention the current studies that show up 3 X's more children with ADHD have vision problems and 3 X's more children with vision problems have ADHD characteristics. Have your child's eyes evaluated today. Go to for doctors who evaulate the vision problems affecting children with ADHD. DM

What is Autism Video

What is Autism? What Causes Autism?

Autism is known as a complex developmental disability. Experts believe that Autism presents itself during the first three years of a person's life. The condition is the result of a neurological disorder that has an effect on normal brain function, affecting development of the person's communication and social interaction skills....People with autism have issues with non-verbal communication, a wide range of social interactions, and activities that include an element of play and/or banter....'s mission is to be the most reliable, timely and complete resource on the internet for brain injury and spinal cord injury survivors. Our hope is that this site will become relied upon as a trustworthy resource for the community and for those who are searching for information.

Real Time Snapshot Of The Learning Process

...To learn from experience, it is essential to know whether a past action was associated with a desired outcome. Now, scientists have demonstrated how this information can be coded by a single cell. The research, published in the July 30th issue of the journal Neuron, provides strong support for a neural mechanism that allows reward signals to be combined over time to drive successful learning....

Biological and Medicinal Properties of Grapes and Their Bioactive Constituents: An Update

The grape is one of the most valued conventional fruits, worldwide. Although most of the parts of the grapevine are useful, primarily, the grape is considered as a source of unique natural products not only for the development of valuable medicines against a number of diseases, but also for manufacturing various industrial products. Over the last few decades, apart from the chemistry of grape compounds, considerable progress has been made towards exploring the biological activities of various grape-derived constituents. Today, it is well established that in addition to serving as food, the grape is a major source of several phytochemicals. The main biologically active and well-characterized constituent from the grape is resveratrol, which is known for various medicinal properties in human diseases. This review discusses the roles of various grape-derived phytochemicals in relation to various diseases.

Comment: I like red wine. The fact it has good stuff in it is good too! Cheers! DM

Genetic risk, not anesthesia exposure, impacts cognitive performance

..A recent study of more than 2,000 identical twins found that medical problems early in life, rather than the neurotoxic effects of anesthesia, are likely linked to an individual's risk for developing learning disabilities....

Tuesday, August 4, 2009

Dr. Julie Ryan Video on Optometric Vision Therapy

Effectiveness of screening preschool children for amblyopia: a systematic review

...Population based preschool vision screening programmes cannot be sufficiently assessed by the literature currently available. However, it is most likely that the present systematic review contains the most detailed description of the main limitations in current available literature evaluating these programmes. Therefore, future research work should be guided by the findings of this publication....

Comments: If the literature on this is so bad that they can't come to a good can vision screening be for amblyopia? Children should have full, comprehensive vision examinations. No ifs. No buts. No maybes. We could eliminate most of the amblyopia in the USA if all infants would participate in the AOAs InfantSee program. Go to today to learn more. DM

Brain Exercise Might Delay Dementia-Related Memory Decline

...Older people who participate in activities that keep their brains sharp may delay the rapid memory decline of preclinical dementia, researchers found.

For each additional activity day spent reading, writing, doing crossword puzzles, playing board or card games, having group discussions, or playing music, older individuals who eventually developed dementia delayed the onset of accelerated memory decline by more than two months (P=0.016), according to Charles Hall, PhD, of Albert Einstein College of Medicine in New York City, and colleagues....

More Vision Wars: Visual Training for Dyslexics

From: Edie Neurolearning Blog: The role of visual challenges in dyslexia has a long and contentious history. Although the authors of the recent consensus statement on Vision and Dyslexia were trying to clarify the most effective approach to diagnosing and treating visual processing issues in dyslexia, their statement is more likely to misinform than inform. [emphasis mine]

While not all children or adults with dyslexia have visual processing problems, many--at least two-thirds in some studies--do. This makes sense from a neurological standpoint, because several of the structural neurological features associated with dyslexia appear to predispose to visual difficulties. ... Consequently, it should not be surprising that their visual movement functions, which are controlled by many of the same neural pathways, are also poorly coordinated.....In one study of dyslexic children, just one type of visual problem, near-point convergence insufficiency, was present in 30-40% of the dyslexic children, compared to just 20% of controls. ... For children with convergence insufficiency, peer-reviewed NIH sponsored research has shown that home therapy can work as can home exercises with computer training, but that in-office therapy shows the best efficacy. ... for children who have both dyslexia and visual problems, interventions (whether visual exercises, vision therapy, or glasses) will often improve their ease and endurance for reading.

Comments: Vision therapy fixes vision problems....and prepares the individual to read more easily, comfortable and efficiently. The latest rounds of attacks by organized medicine do not change this fact. It is sad that some of our MD colleagues do not recognize this. DM

New Theory about Autism Roots

...An estimated one in every 150 children born in the U.S. develops autism, according to the Centers for Disease Control and Prevention (CDC); it is four times more prevalent in boys than in girls. The condition is characterized by cognitive deficiencies and symptoms ranging from antisocial (not responding to one's name and / or avoiding eye contact) to obsessive, repetitive behavior. The most popular theory about its genesis is that there are flaws in several genes passed down through generations of a family that culminate to predispose a child to the disorder, especially if exposed to certain environmental factors such as toxic chemicals or a lack of oxygen at birth....

Comment: Interested in Autism? Read this Scientific American article today.DM

From 2-D to 3-D Sight: How One Scientist Learned to See

Scientific American Interview with Susan Barry, PhD (Stereo-Sue):

Scientific American:...LEHRER: How did you regain 3-D vision at the age of 48?

BARRY: Even though I had three childhood surgeries to "correct" my crossed eyes, I still did not see in 3-D. After the operations, my eyes looked cosmetically straight but they were still slightly misaligned....In my late forties, I consulted a developmental optometrist who prescribed for me a program of optometric vision therapy designed to stabilize my gaze. Since I was cross-eyed, I looked at visual targets with one eye and turned in the other. The vision therapy procedures provided me with the feedback I needed to know where in space each eye was looking. With this feedback, I learned to aim the two eyes at the same location in space at the same time and, to my astonishment, began to see in 3D. Further therapy taught me how to integrate my new 3D views with my former ways of judging depth and distance....

Comment: Click on the title to read more of the interview. DM

Monday, August 3, 2009

Obsessive-compulsive disorder: Nearly a lifetime without treatment

Anthony Barone a long time employee and the first friendly face most folks see as they come to the Illinois College of Optometry is out to help people with obsessive complusive disorders... I've known Anthony for decades, and he represents the very best of ICO and the individual we employ. Click on the title for the story in the Chicago Tribune. DM

Arizona Cardinals wide-receiver, Larry Fitzgerald Supports OVT

Arizona Cardinals 2008 NFC West Champions' wide-receiver, Larry Fitzgerald, is helping eye doctors spread the word to parents that vision problems can interfere with a child's ability to pay attention, read and learn. Tells about his own story and how optometric vision therapy helped him.

Neurobiologist finds adult brain is quite flexible

...In the early 1960s, when Susan Barry was in the third grade, the assistant principal showed up one morning to demote her from the class for above-average students to the special-problems class....A boy was assigned to drag her desk behind her down the hall, and the scraping sound it made on the floor would haunt her for years....This was just one of many humiliations experienced by Barry, who since infancy had suffered with a vision problem that affects millions of children but is still profoundly misunderstood by science....She developed a condition called strabismus, a misalignment of the eyes that causes a variety of conditions; in Barry’s case, cross-eyes....

The Jewish Guild for the Blind’s National Tele-Support Network

...The only one of its kind in the country provides free, weekly telephone support groups facilitated by social workers and psychologists for families of blind, visually impaired or multi-disabled children and teens. The Guild is nonsectarian and one of the nation’s foremost not-for-profit vision healthagencies...