Among the diverse causes of academic failure, specific retardation in reading, spelling, and writing is the salient characteristic of one group of underachievers. Although in possession of at least average intellectual potential, free of severe deficit in vision, hearing, or motor performance, and at least initially unencumbered by social or emotional impediments, these children labor with receptive or expressive written-language tasks. To them the term "specific developmental or constitutional dyslexia" has been applied.
THE PROBLEM OF NOMENCLATURE
These children have been recognized since the turn of the century, and initially the term "congenital word blindness" was suggested as a name.1,2 By the first quarter of the 20th century, Orton's observations regarding frequent laterospatial errors in written expression, including mirror writing, led him to suggest the designation "strephosymbolia" (twisted symbols).3 Orton subsequently elaborated on the syndrome, including various manifestations of reading, spelling, written expression, and oral-language problems that may be encountered in the dyslexic population.4 Critchley developed further the theme of the specific, "pure" syndrome comprising receptive and expressive written language.5,6
However, in the 1940s a theme divergent from the pure constitutional syndrome proposed by Critchley emerged, in which various deviant behaviors were included in addition to those based on language performance.7,8 This trend has complicated the description and classification of underachievers. The result has been the reference to a broader, more heterogeneous group of underachievers for whom initially the term "minimal brain damage" was employed; this has evolved to the current label of "minimal brain dysfunction."9
This classification is also heterogeneous, both in regard to behavioral characteristics (of which 99 have been described) and in regard to implied causes of the condition, since the putative mechanisms have been variously attributed to central nervous system insult, maturational lag, and constitutional differences.
As a consequence of parental and educational concern over academic underachievement of children, federal legislation was enacted in the late 1960s that was designed to help children who were, in the language of the enactment, "specific learning disabled."
Thus, the public response to these imperfectly related concepts of children who had a specific constitutional written-Ianguage disability and the broader group of children who had other learning and behavior disorders was - for the purpose of delivery of remedial services - to merge them under one label that, it was hoped, had educational pertinence.
But the definition written in the law, while it did provide the basis for funding educational remediation programs, confounded rather than clarified the dialogue between those in the medical disciplines and those in education. It also confounded communication among those in the various medical disciplines concerned. However, if one inspects the Congressional definition, it is clear that the legislators placed the emphasis on language underperformance in describing the disability as "a disorder in one or more of the basic psychological processes involved in understanding or using spoken or written language . . . manifested in imperfect ability to listen, think, speak, read, write, spell, or do mathematical calculations."10
Having spoken of "disorder" in the singular, the legislation then proceeded to pluralize the definition to "include such conditions as perceptual handicaps, brain injury, minimal brain dysfunction, dyslexia, and developmental aphasia."
Specifically excluded from the learning disabilities covered in the legislation are learning problems due primarily to visual, hearing, or motor handicaps or to mental retardation, emotional disturbance, or environmental disadvantage.
The pediatrician should be aware that more recent federal legislation has specified the characteristics under which special services to education may be provided. These include deficits in:
1. Oral expression.
2. Listening comprehension.
3. Written expression.
4. Basic reading skills.
5. Reading comprehension.
6. Mathematical calculation.
7. Mathematical reasoning.11
This legislation requires that a diagnostic team ascertain whether a child has a specific selective discrepancy in one or more of these areas. Although the legislation does not specify that a physician be a member of the team, enough latitude is given so that a physician's comment may be solicited by the student or his family and included in the data submitted to show that the child qualifies for special services.
Obviously there are many difficulties when such a broad, inclusionary approach is used, and among them are the wide differences in the various subgroups listed. For example, the term "perceptually handicapped" used in the legislation emphasizes receptive deficits; although these may be present, the equally important retentive and expressive aspects of language function are not mentioned. Additionally, an emphasis on visual perception is implied by the term, whereas the cause of the child's difficulty may well be primarily of a central auditory nature. Further, those who use the term imply that associated motor dysfunctions are involved causally. This has led to the formulation of a therapeutic approach that addresses itself to the perceptual-motor behaviors assumed to be antecedent to and hierarchically necessary for the development of normal language ability.
"Minimal brain dysfunction" is a term that has been associated with 99 specific behavior disorders.9 They can be broken down into four main categories - coordination, attention, language, and perception. However, a child may have a disorder in any one of the four categories independently of the other three. For example, a disorder in coordination may constitute no impediment at all to language development or academic success.
Although disorders of attention of severe enough magnitude will interfere with school achievement, in many instances the term "hyperkinesis" has been applied within the domain of both motor and attention disorders. However, strict criteria are difficult to find that would permit inclusion in or exclusion from the category of hyperkinesis in each case. The clinician should bear in mind that the term is best conceived of as being descriptive rather than nosologic. When restlessness is described as behavior, the prudent examiner will probe for a description of the situations in which the behavior tends to occur. That is, does it occur throughout the day and each day of the week, only in the classroom, or only when the child is confronted with specific academic tasks? (The first condition is suggestive of a more severe persistent attentional problem; the last raises a question of a specific deficit in an academic skill.)
Those who use the "minimal brain dysfunction" concept often refer to so-called soft neurologic signs. These signs are of a motor nature and are taken to be indications that the person has a central nervous system dysfunction similar to those traditionally associated with acquired disorders of the nervous system. However, the use of the word "soft" should cause the clinician to beware, for it means that the symptoms may not be recognized by all the examiners of a given patient. The Isle of Wight studies attest to the lack of correlation between "soft neurologic signs" and cognitive functions related both to intellect and to language usage. In these studies, 16 per cent of a category of exceptionally gifted children had five to 10 soft neurologic signs, whereas a comparable 19 per cent of those with specific reading disabilities also had five to 10 such neurologic signs.12 Finally, it would appear that many of those who employ the term "minimal brain dysfunction" tend to attribute the various dysfunctions to an acquired insult to the central nervous system, although in most instances this cannot be confirmed as being causal.13
"Dyslexia." When this term is employed in adult neurology, it refers to an acquired disorder of reading in which there may or may not be an associated disorder of writing (dysgraphia). However, in the pediatric setting, those who use the term usually include disorders of spelling, although the salient feature is likely to be a disturbance in reading performance.
At times the concept of a specific syndrome is advanced. However, despite the clustering of associated cortical (parietal) symptoms and signs in many of these children, there is sufficient heterogeneity in the clinical expression to weaken the argument that it is a pure syndrome.14
Additionally, those who use the term "dyslexia" almost always imply a constitutional, genetically determined basis for the clinical behaviors. Despite a high frequency of occurrences of familial involvement,15 not every patient demonstrates a positive family history. This had led some to suggest that the term "specific reading disability" or "specific reading retardation" be used to describe persons whose discrepant behavior affects their reading, with the implication that spelling is also affected in most instances. One is more secure in using the term developmental dyslexia in the absence of a history of brain damage and with the presence of a positive family history.
"Constitutional aphasia" is also a term that implies the absence of a historical event that could have caused the language impairment. This term is used most often to describe children who have difficulties in oral expression, yet it should include the receptive-language component as well. Thus, constitutional aphasia connotes a more widespread language impairment than dyslexia, which involves the written-language process primarily.
In this issue of Pediatric Annals the term developmental dyslexia means a constitutional and often genetically determined disparate reduction in the rate and quality of written language skills, such as reading, writing, and spelling. These may or may not be associated with such other problems as
1. Difficulty with symbolic manipulation i.e., +, -, X, -).
2. Disordered development of concepts of time (i.e., dates, hours, sequences of days and months).
3. Disordered development of concepts of space, both personal and extrapersonal (i.e., relation of objects in space, manipulation of geometric forms, cut-out puzzles, up, down, right side, left side).
Others, however, have suggested strict behavioral descriptive terms for children with this disorder, such as "specific reading retardation"16 or "unexpected reading failure.'17
The nature of the clinical assessment will be influenced by the child's age, the referral source, and the type of practice setting in which the pediatrician sees the patient. In the case of the younger patient (preschool to eight or nine years), more time will be spent with the parents for the elucidation of historical details. It is essential that there be contact with the parents if the child is being assessed for potential specific academic underachievement. With the older child, sufficient time should be set aside for interviewing him, both alone and in the presence of his parents.
In my practice I routinely see the student first, alone, and obtain the student's sense of why he or she is being seen by the physician and what his or her perception is of any academic problems. After my clinical examination, the parents are invited in to voice their concerns in front of the student, for often the student does not have a clear idea of what the parents' concerns are, and this only complicates the validity of his own concerns.
Cognizance of the source of the referral and the nature of the referral source's chief complaint should be made. Most commonly the referral will be from the school or the parents (or both), but in the older student, self-referral or referral from social agencies may occur. Some physicians will be practicing within a multidisciplinary group in which audiology, ophthalmology, educational psychology, and speech pathology may be represented. With ready access to these other disciplines, the time commitment for the physician's examination may be reduced. For the private practitioner, however, expansion of personal skills in the conduct of the examination or reliance on outside sources of data will be necessary.
The response to the referral source must be appropriate to the referral question, but it is wise also to solicit the student's own concerns and perceived reasons for seeing the physician. Although providing a diagnostic label is of help, particularly with regard to receipt of remedial services, the physician should attempt to answer questions that the family and the student may have regarding the nature of the problem. The most common referring complaint in school-age children with average intelligence will be that of academic failure, with the physician assisting in the determination of whether or not this represents specific underachievement (e.g., underachievement in reading [and/or] in mathematics.)
Thus, the examination must rule out peripheral sensory deficits, organic and potentially progressive central nervous system disorders, any primary underlying psychiatric disorder, lack of motivation for academic success, limited educational experience (or inappropriate educational experience), and cultural deprivation of sufficient magnitude to explain the degree of academic underattainment. However, the experienced examiner will have encountered cases in which any of the above may coexist to some degree with the written-language underachievement. He must then make the judgment that these various deficits are not the primary causes of the written-language underachievement and render a statement as to his sense of the appropriateness of specific educational intervention. Family and patient history. Among the data that may have potential value and that should be recorded routinely at some point are (1) a family history of specific reading problems (problems that may have been partially remediated or compensated for by the time the family member has reached adulthood but still may be manifest in such things as residual spelling problems); (2) the patient's history - prenatal, perinatal, and postnatal (birth weight should be obtained: lowweight-for-date infants may be at risk for future neurologic defects); (3) childhood history of trauma, illness, or accidental ingestion of substances requiring medical attention.
In our experience with developmental dyslexies, the family history is the factor among those listed above that is most apt to be positive. However, a negative family history does not exclude the diagnosis of developmental dyslexia. Likewise, the presence or absence of apparently significant complications at birth may or may not clarify the cause of the patient's problem; we have seen a number of normal-achieving school-age children who have had histories of perinatal trauma seemingly as significant as those reported for some of the underachievers.
The developmental history is important not only with regard to motor milestones but also for the linguistic milestones of first words, first complete sentences, letter naming, articulation, oral fluency, color naming, age at apparent manual lateralization for pencil or crayon use, quality of drawings, attention as assessed by ability to persist at a given task, and responsiveness to oral speech.
Such information may be available from preschool records, if they exist, and from school entrance data, as well as from the parents. However, in the older child, passage of time obscures recollection of these specific items. Generally, the accuracy of parental observation increases when there is more than one offspring and particularly when there is an affected older sibling. If possible, school records should be made available for perusal. However, some examiners prefer to defer anamnestic* data until the initial evaluation has otherwise been completed, in order to make such an evaluation "unbiased."
In some instances, description of the sleeping pattern of the child and of apparent alertness, particularly as the day progresses, provides a clue that relative sleep deprivation may be a factor in underachievement or reduced attention.
When the history is one of apparently normal development with only recent reduction in academic performance (particularly in cases where all areas of academic performance are affected), the examiner should be alerted to a possible primary psychiatric disorder or the development of organic central nervous system disease. The latter may be supported by asymmetric findings on the neurologic examination or the results of the formal psychometric assessment, if performed, which then may warrant further diagnostic evaluation pertinent to organic nervous system disease.
The examiner should be encouraged to carry out a relaxed and supportive interview in which information pertinent to the student's interests and perceived successes and failures in and out of school is described - that is, is there apparent talent or interest in music, art, mechanical skills, or athletic activities? Since most academic experiences depend on reading performance, most school subjects may have been perceived by the patient as being of low interest whereas the above-listed activities merited his attention.
The social behavior of the child should be described. How does he relate to others within the family and in school? Is the child the object of scorn, perhaps resulting from the perception of him by his peers (or parents) as being "different"? Is there a compensatory bravado masking a core of personal insecurity based on poor academic performance? Has the child acted out in an aggressive manner, perhaps to the extent of delinquency? Or is the child withdrawn and passive, perhaps denoting a low-risk-taking adjustment? Throughout the history-taking portion of the examination, one should note the demeanor and affect of the child, his oral language as manifested by oral fluency, the words used (number and complexity), and the rules of syntax that appear to have been incorporated in the patient's oral language. Likewise, subtle pacing of the rate at which questions are asked and the complexity of the questions themselves may reveal evidence of receptive-language impairment.
Assessment of oral-language performance is commonly neglected. This should not be the case, for there is increasing evidence that children with oral-language problems are prone to difficulties with written language and that one may be treating a child who has a specific language disability in which the earliest manifestation is a problem in speech production or speech perception.18
The physical and neurologic examination. As part of the examination, eye, hand, and foot preference should be recorded. However, in individual cases, sinistral preference or cross-lateralization lacks diagnostic specificity. A screen of visual acuity and hearing acuity can be carried out by using an A. M. A. reading card for near vision, and inexpensive audiometrie devices or acuity to a ticking watch provides a gross screen of high-frequency hearing. When specific questions regarding vision and hearing have been raised, appropriate additional consultation is advisable.
There has been increasing concern regarding the necessity for early identification of children who have a propensity for academic underachievement.
The examination described below may be less pertinent for children of age four to six years. Some modification in the procedures can still be carried out, but specific attempts at assessment have been developed, with relatively high reliability, which include screening devices that can be incorporated into the office examination by the pediatrician or by a qualified assistant working under the supervision of the physician. These sample a spectrum of speech, writing, and motor behaviors, which may be as simple as letter naming.19,20
A complete neurologic examination should be carried out in which the examiner can record unequivocal abnormalities. One should be cautious about minor deviations in motor-system performance, with the possible exception of the observation of associated movements persisting in the child of nine years or older. Cortical sensory testing may on occasion reveal difficulty in right-left orientation and in finger localization. However, in the child below the age of eight years, variance in performance can be discounted, and beyond that age it carries little significance in isolation from other symptoms. More often, as the physician assesses mental status while taking the patient's history, unusual difficulties in spatial and temporal concepts will be observed.
Some estimate of intelligence may be inferred by taking into account the chronologic age, socioeconomic background, and educational experience of the child. However, underestimates of intelligence are prone to occur in the office examination of youngsters with oral expressive difficulties or with deficits in receptive-language performance. Assessing language performance. A qualitative and semiquantitative assessment of oral reading skill can be made with the Gray reading inventory, which is readily available and takes up little space. The patient reads aloud each graded paragraph. The rate of reading, the quality of reading performance, and the recall of what has been read should be noted. One should remember that the very bright child will be expected to read above age or grade level. Word substitution, reversal of letter sequence, and letter or word omission, as well as slow rate, are commonly observed in the dyslexic.
At times, despite these apparently weak wordattack skills, some reading-impaired students may make a fair approximation through substitution of a word or verbal content of the sentence. Variable recall or comprehension of what has been read is characteristic. Samples of written expression, spontaneously and to dictation, should be performed. The examiner should note the complexity of the words selected by the patient in the spontaneous written sentence as contrasted to the oral language noted earlier in the examination, along with the frequency of spelling errors, letter reversals, and manual execution of the letter forms themselves.
Letters most often reversed are b, d, p, and q. Patients with severe dyslexia, even at the age of 10 or 12, may create novel letters, such as Ò or f. Phonetic equivalents may be made in the spelling, or the written word may be totally incomprehensible. Boder21 has suggested that analysis of the types of errors in spelling may provide a classification of dyslexies as having visual processing difficulties or auditory-processing difficulties, or both. Recently, there have been a number of attempts to subcategorize the types of dyslexia.22"24 If cursive writing is used, a looping of the i with, at times, omission of the dot above may imply insecurity on the part of the writer as to whether e or i was the appropriate letter.
Figure 1. Comparison of spontaneous writing and writing to dictation in a 12-year-old right-handed boy with a WISC R full-scale IQ of 120. The child is orally fluent, and his teachers' chief complaints concerned his erratic grades and poor spelling, writing, and composition. Top: Spontaneous writing: "I want to go skiing at Terry Peak." Bottom: Writing to dictation: "Next year in science class we will dissect an embryo pig. I look forward to this experience with fascination and anticipation."
Similar qualitative performance errors may be noted - that is, n, m; u, w; a, o. Or the child may insert a capital B in midword if he cannot recall which direction the stem of a lower-case b takes - right or left, above the line or below. In dictating sentences for the child to copy, match them with what you perceive the interests of the student to be and with what the interview suggests are within his oral vocabulary. It is not unusual for both penmanship and spelling to deteriorate when a dyslexic child writes to dictation (Figure 1).
Psychometric testing. The approaches outlined above provide only qualitative data of writtenlanguage performance. But for the experienced examiner they provide useful information from which diagnostic inferences may be drawn. Formal psychometric testing, with standardized achievement tests, will be required for quantitative judgments.
Additionally, copying of designs (some of which may be taken from the Bender Visual Motor Gestalt Test) and samples of mathematical computation in writing should be obtained. These may be relatively intact, in contrast to the patient's disparate performance with written language.
If not already available to the examiner, individual formal psychometric testing should be carried out, from which more precise statements regarding the degree of underachievement may be made.
Other tests. Although the hallmark of specific developmental dyslexia is the discrepancy between apparent intellectual potential and actual achievement in reading and spelling, the central process(es) producing the behavior pattern provides the suggested educational remediation plan. A common criticism by educators of the reports provided by medical and psychologic facilities is that although a diagnosis is provided, few if any suggestions regarding practical alterations in the educational program accompany the diagnostic report. This is one advantage of the so-called team approach, in which those experienced in the field of remediation may be able to develop constructive educational alternatives based on the assessment.25
Routine electroencephalography does not improve diagnostic acumen. This tool fails the test of predicting reading failure. EEG should be employed only when an associated or underlying seizure disorder is suspected or some other organic, potentially progressive central nervous system disorder is under consideration. Additional neurologic diagnostic studies are warranted only when, in the judgment of the examining physician, an underlying active central nervous system disorder is a reasonable diagnostic possibility. On occasion, however, family concern or concern on the part of the referring party may be satisfied if an electroencephalogram or other noninvasive diagnostic procedure is carried out. This is not warranted as a routine measure, however.
Results of the evaluation, the diagnosis and its implications, and the need for specific educational remediation should be discussed frankly with the patient and his family. The physician should use terms meaningful to them and should obtain their permission to communicate his findings to the patient's school.
Both patient and family should be made aware that the child's impaired performance is selective rather than general and that it is part of the continuum of aptitudes rather than a disease.
Medications to increase alertness may assist the child who has a primary or additional attention disorder, but these agents hold no benefit for the developmental dyslexic with normal attention span.26
Understanding and acceptance of the diagnosis open the way for effective remediation. The patient and family may be assured that the prognosis, particularly for the bright dyslexic, need not be bleak, although the path to success will not be untroubled.27,28 My own experience suggests that the prognosis is improved when one or more of the following obtains: early and appropriate identification, only mild reduction in reading or spelling skill, early and appropriate remediation, high native intelligence, stable and supportive home and school environments, middle or upper socioeconomic class, high skill in another academic or nonacademic area with social merit (e.g., mathematics, music, art, or athletics).
When remediation programs are not available in existing educational facilities, the pediatrician may play an important role as an advocate for the development of programs appropriate to his patient's needs. The physician may be further stimulated to assert his role on behalf of these students when it is recognized that the frequency of specific reading retardation appears to equal or exceed the combined frequency of mental retardation, cerebral palsy, and epilepsy - which makes this condition an important public health problem.
1. Morgan, W. P. A case of congenital word blindness. Br. Med. ]. 2 (1896), 1378.
2. Hinshelwood, J. A case of dyslexia: A peculiar form of wordblindness. Lancet 2 (1896), 1451-1454.
3. Orton, S. T. Specific reading disability - strephosymbolia. J.A.M.A. 90 (1928), 1095-1099.
4. Orton, S. T. Reading, Writing, and Speech Problems in Children. New York: W. W. Norton & Company, 1937.
5. Critchley, M. Mirror- Writing. London: Paul Trench Trubner & Company, 1928.
6. Critchley, M. The Dyslexic Child, Second Edition. London: William Heinemann, 1970.
7. Strauss, A. A-, and Werner, H. Disorders of conceptual thinking in the brain-injured child. /. Nerv. Ment. Dis. 96 (1942), 153172.
8. Strauss, A. ?., and Lehtínen, L. E. Psychopathology and Education of the Brain-Injured Child, New York: G rune & Stiatton, 1947.
9. Clements, S. D. Minimal Brain Dysfunction in Children. NINDB, Monograph No. 3. Washington, D.C.: U.S. Department of Health, Education, and Welfare, 1966.
10. Public Law 91-230. The Elementary and Secondary Education Act Amendments of 1969. Title VI: The Education of the Handicapped Act, April 13, 1970.
11. U.S. Department of Health, Education, and Welfare. Office of Education. Assistance to states for education of handicapped children: Procedures for evaluation of specific learning disabilities. Federal Register (Part 3, December 29), 1977.
12. Rutter, M., Graham, P., and Birch, H. G. Interrelations between the choreiform syndrome, reading disability and psychiatric disorder in children of 8-11 years. Dec. Med. Child Neurol. 8 (1966), 149-159.
13. Schmitt, B. D. The minimal brain dysfunction myth. Am. /. Dis. Child. 129 (1975), 1313-1318.
14. Benton, A. L. Developmental dyslexia: Neurological aspects. Adv. Neurol. 7 (1975), 1-47.
15. Finucd, J. M., et al. The genetics of specific reading disability. Ann. Hum. Genet. 40 (1976), 1-23.
16. Rutter, M., and Yule, W. The concept of specific reading retardation. J. Child Psychol. Psychiatry 16 (1975), 181-197.
17. Symmes, J. S., and Rapoport, J. L. Unexpected reading failure. Am. i. Orthopsychiatry 42 (1972), 82-91.
18. Menyuk, P. Relations between acquisition of phonology and reading. In Guthrie, J. T. (ed.). Aspects of Reading Acquisition. Baltimore: Johns Hopkins University Press, 1976, pp. 89-110.
19. Jansky, J. J., and deHirsch, K. Preventing Reading Failure: Prediction, Diagnosis, Intervention. New York: Harper & Row, Publishers, 1972.
20. Colligan, R. C, and O'Connell, E. J. Should psychometric screening be made an adjunct to the pediatric preschool examination? Clin. Pediatr. (Phila.) 13 (1974), 29-34.
21. Boder, E. Developmental dyslexia. A diagnostic approach based on three atypical reading-spelling patterns. Dev. Med. Child. Neurol. 15 (1973), 663-687.
22. Johnson, D. )., and Myklebust, H. R. Learning Disabilities: Educational Principles and Practices. New York: Grane & Stratton, 1967.
23. Mattis, S., French, J. H., and Rapin, I. Dyslexia in children and young adults: Three independent neuropsychological syndromes. Deo. Med. Child Neurol. 17 (1975), 150-163.
24. Rourke, B. P. Reading, spelling, arithmetic disabilities: a neuropsychologic perspective. In Myklebust, H. R. (ed.). Progress in Learning Disabilities, Volume 4. New York Grane & Stratton, 1978, pp. 97-120.
25. Rawson, M. B. Developmental dyslexia: Educational treatment and results. In Duane, D. D., and Rawson, M. B. (eds). Reading, Perception and Language. Baltimore: York Press, 1975, pp. 231-258.
26. Gittelman-Klein, R. Short- and long-term effects of methylphenidate on cognitive performance in learning disability children. In Proceedings of the 20th International Congress of Psychology. Tokyo: University of Tokyo Press, 1974.
27. Rawson, M. B. Developmental Language Disability: Adult Accomplishments of Dyslexic Boys. Baltimore Johns Hopkins University Press, 1968.
28. Thompson, L. J. Language disabilities in men of eminence. Bull. Orton Soc. 19 (1969), 113-118.
29. Duane, D. D. A neurologic overview of specific language disability for the non- neurologist. Bull. Orton Soc. 24 (1974), 5-36.