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American Orthoptic Journal Back Content
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Volume 49, 1999, p. 175–179
An Ophthalmologist's Approach to Children with Visual Perception and Learning Differences (Abstract)
Harold P. Koller, M.D.
INTRODUCTION
Traditionally when a child whose chief complaint is a reading or learning problem presents to the pediatric ophthalmologist, the primary focus of the examination is to rule out the presence of organic eye disease and recommend optical, pharmacological or surgical treatment. Previously there has generally been little interest on the part of most Eye M.D.'s to become involved in the science of learning and communication. On the contrary, organized optometry has professed an interest in this area and, over the past thirty years, has evolved the subspecialty of Developmental Optometry to address these patients' problems.' It is time that ophthalmologists develop an awareness and understanding of the science of learning because the public perceives the Eye M.D. as the expert in the field of visual perception and processing and well as visual function and eye disease.
Medical science is now moving rapidly into the era of multidisciplinary approaches to disease detection and treatment. This is obvious with the introduction of gene therapy, alternative medicine and robotic surgical techniques. The merger of technology, biologic science and human behavior is fast approaching. The public is most concerned about educational and health care issues in the United States today. The science of learning, including auditory and visual perception, is truly a hybrid of these two disciplines. Although our pediatric, neurology, psychiatry and psychology colleagues have traditionally diagnosed and treated children with learning differences, the fact remains that ophthalmologists are often the physicians initially consulted and we should at least know the "language" of the science of learning. This will be presented in this article.
LEARNING DISORDERS
There are four major categories of learning disorders.2 Learning differences is the preferred general term, however, since some children exhibit diminished scholastic performance as a result of poor teachers, parental disinterest or neglect, actual systemic disease as well as simply poor motivation or low intelligence. These four categories or divisions include 1) speech and language disorders 2) nonverbal learning disorders 3) attention deficit/hyperactivity disorders and 4) pervasive developmental disorders. Other, not purely ophthalmic conditions that can at times affect learning include acephalgic migraine, Tourette Syndrome and certain psychiatric disorders.
SPEECH AND LANGUAGE DISORDERS
Developmental speech and language disorders are frequently the initial indicators of a true learning disability. These children have one or more of the following difficulties: trouble producing speech sounds; trouble using spoken or written language to communicate; as well as trouble understanding what people say or write. Articulation, expressive and receptive language disorders are all subdivisions of the main category. Hearing and vision are usually normal in these individuals. Reading requires the centers in the brain concerned with vision, language and memory to integrate and efficiently coordinate the complex series of tasks required to interpret the written symbols on a page and extract meaning from them.3 Auditory processing is mediated similarly to visual processing.4
The most common receptive language disorder is functional dyslexia. Shaywitz believes that dyslexia is "characterized by an unexpected difficulty in reading in children and adults who otherwise possess the intelligence, motivation, and schooling considered necessary for accurate and fluent reading." 5 It occurs in between 5% to 17.5% of children and with an equal sex distribution. Gene linkage studies reveal abnormalities on chromosomes 6 and 15 in these individuals. The processing defect is now felt to be in the area of phonologic awareness. An ophthalmologist can suspect the diagnosis of dyslexia by merely asking the parent if the child has difficulty reading or sounding out words as opposed to whole word recognition. Letter reversals, which often represent mere symbol confusion, are most often outgrown and do not imply the presence of dyslexia.
NONVERBAL LEARNING DISORDERS
Nonverbal learning disorders (LD) are characterized by verbal ability being usually better than spatial conceptualization. Foss states, "Reading skills in word identification, phonetic analysis and oral reading of passages usually surpass comprehension of implicit semantic relationships among words and of literal and inferential meanings of passages. Spelling skills are strong, handwriting is poor and other skills for organizing and producing written work are problematic."6 Visual imagery and visual memory are poor in these individuals. This disorder is most often under diagnosed and least understood although an ophthalmologist can suspect it with the simple visual memory test shown in the Figure.7 Children with this disorder are those who can read a paragraph but 15 minutes later do not recall the significance of what they read nor its implications in relation to past experiences or future possibilities. Studies indicate that higher brain centers are involved in nonverbal LD more than in pure dyslexia.
ATTENTION DEFICIT/HYPERACTIVITY DISORDERS
Attention deficit/hyperactivity disorder is a type of behavior in children and adults characterized by three main features, singly or in combination. They are inattention, impulsivity and hyperactivity. It is implicated in learning difficulties and is said to affect 5% to 10% of school aged children. It occurs more frequently in males than females by approximately 10:1. The right sided frontal striate system of the brain has been postulated as the site of pathology in AD/HD.8 Shifting thoughts and easy distractibility are manifestations of this disorder. An ophthalmologist or orthoptist can easily suspect this when observing a pediatric patient in the exam chair pushing all the buttons and foot pedals plus getting out of the chair even when instructed not to. We have all experienced this type of patient. The Diagnostic and Statistical Manual of Mental Disorders IV applies the term ADHD to children and adults who display certain characteristic behaviors over a period of time.9 This type of LD is frequently misdiagnosed and/or over diagnosed today.10 It has been the subject of numerous weekly national magazine articles, television news stories and other media attention the past several years.11, 12
PERVASIVE DEVELOPMENTAL DISORDERS
Pervasive developmental disorder (PPD) is now often referred to as Autism Spectrum Disorder (ASD). It is a group of neurologically based disorders of development, most often of unknown etiology, in which there are three main developmental deviations from normal. These include 1) social relatedness and social skills 2) communicative use of language and 3) a limited but intense range of interests. These three characteristics can range from mild to severe and define the entire PDD or ASD spectrum.13 Asperger syndrome14 is an example of a rather high functioning class of PDD patients while severe classic autism is an example of the lowest functioning class. The most frequent ophthalmic complaint which should suggest a diagnosis of Asperger syndrome to the Eye M.D. is a lack of sustained eye contact in a young child, aged 2 to 5, with a normal eye exam.
OTHER CONDITIONS ASSOCIATED WITH LEARNING DIFFERENCES
Tourett Syndrome is a tic disorder exhibiting involuntary muscular movements, uncontrolled vocal sounds and inappropriate words. These symptoms begin between the ages of 2 and 16 with males being 3 to 4 times more often affected than females. Frequent blinking over a long period of time is usually the presenting eye complaint. If no refractive error, allergic conjunctival or lid involvement or internal ocular pathology is present, suspect Tourette syndrome. Difficulty concentrating during the involuntary tic episodes can influence learning efficiency.15
Pediatric migraine can influence learning and studying at times, especially when ophthalmic migraine symptoms predominate. Often in children the acephalgic varient is present which can go undiagnosed if the right questions are not asked of the child or parents. Many children with migraine experience two or more of the following symptoms with or without an accompanying headache.16 They may have a history of infantile colic or frequent febrile seizures, lactose intolerance, motion sickness, sleep disturbances including night terrors, unexplained abdominal discomfort including pain and/or nausea, unusual sensitivity to light, noise or smell, a type "A" personality resistant to procedural change, and intermittent unexplained blurry vision in the presence of a normal eye exam. This latter symptom can be somewhat annoying in the classroom and likely represents a pediatric version of the classic adult scotoma. Micropsia, macropsia and metamorphopsia as in the "Alice in Wonderland" syndrome can all be part of a child's systemic vascular spasm/dilitation disorder we now know as migraine. Learning can be temporarily disrupted by migraine. It is a diagnosis of exclusion, so if symptoms persist, especially with a severe headache, brain imaging with enhancement should be ordered.
Psychiatric conditions such as mood disorder, depression and anxiety can at times affect learning.17 Social factors such as poor schools and instruction, dysfunctional or abusive family environment or low intelligence are also reasons for poor academic performance.
REFFERAL AND TREATMENT OPTIONS
A multidisciplinary team must be assembled and utilized to enable any child or adult with a learning difference to be helped and remediated.18 The initial step is to have a comprehensive professional neuropsychological evaluation by a licensed neuropsychologist/school psychologist. Once the diagnosis or diagnoses are determined the best team of experts can be utilized to help the child to achieve his full academic potential. Children with language based disorders including dyslexia require a homework tutor, a trained certified reading teacher and a speech and language pathologist. Children with a nonverbal learning disorder may also require a homework tutor but they need an occupational therapist above all to help them learn spatial relationships. An educational psychologist and family therapist are also helpful. High cognitive skill training is necessary to allow the normally functioning parts of the brain assume some of the functions the pathological sites had, much like the rehabilitation specialists and physical therapists do for stroke victims of closed head trauma patients after accidental brain injury ADHD is typically treated by the pediatrician or primary care practitioner as well as a pediatric neurologist or developmental specialist with pharmacological agents. Behavior management and parental training by a family therapist or psychologist is also helpful. PDD and Tourette Syndrome as well as migraine are usually treated by the pediatric neurologist. A pediatric psychiatrist may be helpful in any of the LD classifications if self esteem problems and abnormal behavior and peer or family conflict arises. If the school system does not respond positively and effectively to the neuropsychologist's report it is often effective to engage at attorney expert in the field of educational and disability law to persuade the district into effectively addressing the student's special scholastic needs. While the ophthalmologist obviously will not actively participate in the educational remediation of his patent after providing optimal professional eyecare, he or she should be able to direct the family to the appropriate professional best able to undertake the task of helping these children learn more efficiently. He should partner with the pediatrician, the neuropsychologist and the school to assist this progress. Diagnosis and remediation should be coordinated by the pediatrician or other primary care physician and the neuropsychologist with mandatory dialogue with the school. By having a "feel" for the subject, the Eye M.D. and/or orthoptist can provide the first step in directing the family where to get the best help available.
REFERENCES
1. Scheiman MM, Rouse, MW: Optometric Management of Learning Related Vision Problems, St. Louis, MO; Mosby, Inc.; 1994.
2. Koller HP, Goldberg KB: A Guide to Visual and Perceptual Learning Disabilities. Current Concepts in Ophthalmology, 1999;7:24-28.
3. Council for Exceptional Children (CEC Today: Reading Difficulties vs. Learning Disabilities 1997;4:1.
4. Welsh LW, Welsh JJ, Healy MP: Learning Disabilities and Central Auditory Dysfunction, Ann Otol Rhino Laryngol, 1996;
5. (2)
5. Shaywitz S: Dyslexia: current concepts, New Eng J Med; 1998; 338:307-3 11.
6. Foss JM: Nonverbal learning disabilities and remedial interventions. Ann Dyslexia 1991; 41: 129-131.
7. Koller HP: Recognize the signs of learning dis abilities, EYENET May 1999, Volume 3, No. 5.
8. Heilman KM, Voeller KKS, Nadeau SE: A possible pathophysiologic substrate of attention deficit hyperactivity disorder, Child Neurol, 6:76-81.
9. American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders (4th ed.). Washington: American Psychiatric Association, 1994.
10. Carey WB: Problems in diagnosing attention and activity: Pediatrics, 1999; 103:664-667.
11. Gibbs, Nancy. The Age of Ritalin, TIME, Nov. 1998, pp. 86-96.
12. Hancock, LynNell: Mother's Little Helper, NEWSWEEK, March 1996, pp. 50-56.
13. Greenspan S, Wieder S: The Child with Special Needs, Reading, MA, Perseus Books. 1998.
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