LEARNING DISORDERS
Learning disorders or disabilities (LD) include a large and heterogeneous group of low severity-high incidence disorders, all characterized by “persistent difficulties in coping with academic skills (learning) due to problems with efficient reading (Dyslexia), writing (Dysgraphia), calculations (Dyscalculia) or in other processing functions, which contribute to learning and are not caused by low intelligence quotient (IQ), visual/hearing handicaps or extraneous factors like parental education and family environment".
These children are not intellectually disabled and have normal or even above average IQ.Prevalence: Although frequently underdiagnosed, LDs are estimated to be present in ~5-15% of Indian school children, almost six times more common in boys than in girls.
Pathogenesis: Achievement of academic skills requires normal development of many domains including: (a) attention span, (b) cognitive function, (c) memory, (d) speech and language, (e) neuromotor coordination, (f) visual-spatial capability, (g) temporal-sequential order, and (h) personal-social relationship.
Children with LDs have abnormalities in either all (generalized learning disorders) or some of these fields (specific learning disabilities or SLDs).
Etiology: Exact etiology of LDs is difficult to ascertain in majority of cases, though some inherent or environmental factors have been associated with higher risk, as follows:
a. Prenatal factors, e.g. maternal malnutrition, smoking, alcoholism, intrauterine infections and placental insufficiency, e.g. toxemia, etc.
b. Perinatal complications, e.g. birth asphyxia, hypoglycemia, hyperbilirubinemia, etc.
c. Postnatal problems, e.g. malnutrition, anemia, head injury, lead poisoning, drugs, e.g. anticonvulsants, chronic infections and illnesses, e.g. epilepsy.
d. Genetic defects, e.g. Down syndrome, Turner syndrome, Klinefelter syndrome, Fragile X syndrome, Duchenne muscular dystrophy, phenylketonuria, etc.
About 25-65% dyslexic children have a parent or sibling with dyslexia. Some of them have been identified to have under-activation of posterior brain regions and overactivation of anteroinferior frontal regions during the reading process.
Clinical presentation: LDs in children mainly include three different types of presentations-dyslexia (70-80%), dysgraphia (30-40%) and dyscalculia (15-20%), with frequent overlapping or co-existence.
Dyslexia (Reading disability) is the commonest SLD, characterized by persistent, unexpected difficulty in reading in children or adults, who otherwise possess normal intelligence, motivation and opportunities to learn. Proper comprehension of written and oral words requires phonetic processing, i.e. segmentation of each word into smaller units, before central decoding. Dyslexic children lack this ability of segmentation, leading to slow and incorrect reading, skipping words and lines or substituting common phonetic words. These children like to listen to stories but find it difficult to read them. Dyslexia usually manifests when the formal reading starts, i.e. in first standard of the school, when the focus is on reading to learn than on learning to read.
Dysgraphia (Writing disability) presents with problems in hand-writing, e.g. frequent errors in spellings, grammar and sentence formation and shape and size of written alphabets. Children have difficulties in copying from the board and often produce a disorganized text that is difficult to follow. Dysgraphia is almost always associated with dyslexia and is usually not recognized till II/III standard of the school, when written work increases.
Dyscalculia (Mathematical disability) is usually picked up last in V/VI grade or even later, when complex calculations are introduced in schools. Dyscalculia presents with problems in identifying numbers, retrieving arithmetic combinations and understanding language of mathematics, e.g. numbers and symbols. Students may reverse numbers or make errors while reading them aloud.
These problems are usually seen in conjunction with dyslexia or dysgraphia, Mathematical calculations require ability to understand words associated with arithmetic operations and word problems, which can aggravate difficulties in acquiring mathematical skills.
Other types of SLDs, e.g. dysorthographia denote spelling difficulties and dysnomia refers to difficulty in finding correct word/s for expression. Uncommon LDs includes auditory processing disorders (difficulty to comprehend sounds), language processing disorders (difficulty to understand spoken words), non-verbal learning disabilities (difficulty to understand non-verbal clues) and visual perceptual deficits (difficulty to understand visual clues).
Some children with LDs also have comorbidities, e.g. problems in attention span (attention-deficit hyperactivity disorder), neuromuscular coordination (Apraxia) and personal-social adjustments or social communication disorders (autism spectrum disorders). Many of them
TABLE 3.12: Early indicators of learning disabilities
• Pre-school
- Delayed language development
- Difficulties in learning colors, shapes, etc.
- Difficulties in learning alphabets, numbers, etc.
- Problems in pronunciation
• Early-school
- Slow development of vocabulary
- Repeated spelling mistakes in reading/writing
- Letter reversals (b/d), inversions (m/w), etc.
- Problems with left-right discrimination
- Illegible hand writing
• Late-school
- Difficulty in rhyming words
- Difficulty in written expression
- Difficulty in calculations
also develop secondary behavioral problems, e.g. frustration, low self-esteem, anxiety neurosis and ticks. Diagnosis: LD is a leading cause of poor school performance and the role of school-teachers is vital in early recognition and referral of these children as also the role of pediatrician to guide parents correctly. Some common indicators for suspecting LD in a child are listed in Table 3.12, though it can be diagnosed only after the formal education starts or later, provided there is evidence of onset during the years of formal schooling.
Assessment for LD should begin with assessment of-
(a) educational history and (b) class-room activities, (c) Intelligence Quotient, (d) visual and hearing functions, followed by, (e) formal psychometric (processing and learning ability) testing.
Formal evaluation of these children involves a battery of specific tests, e.g. Woodcock-Johnson test of achievement, Wechsler individual achievement test, etc. or locally developed tests, e.g. National Institute of Mental Health and Neurosciences (NIMHANS) index. NIMHANS index test differs for children aged 5-7 years (Level I) and 8-12 years (Level II) and has the advantage of availability in Hindi and some regional languages apart from in English.
However, before interpreting these tests, it is important to ensure that these children have:
a. Normal Intelligence Quotient (IQ) on standard IQ tests,
b. Normal visual and hearing functions on relevant assessments,
c. Tests are administered in the language that they understand
Management of LDs requires cooperation from child, parents, peers and school teachers and should involve school counsellors, pediatricians, psychologists, psychiatrists, social workers and education consultants. Important principles of management of these cases
include (a) parental counselling, (b) remedial education, (c) curriculum modification, (d) bypass strategies with strengthening of un-affected skills, (e) accommodative provisions during teaching and examinations.
Schooling: While these children have problems in coping with routine pace of learning, it is preferable to continue regular schooling with suitable modifications,
e. g. small-group teaching by specially trained teachers (Special educators) rather than to shift them in special schools. Teachers should be sensitized about the limitations and needs of a child with LD. Under the Right to Education (RTE) Act, all SLD children should be taught in regular schools with provision of a special educator in each school.
Remedial education includes: (a) assessment of the child's strengths and weaknesses in academic skills, (b) altering the pace and mode of teaching, (c) development of an individualized education program with well-defined short-term and long-term goals, (d) and monitoring the child's progress. Interventional sessions, (i.e., twice-or thrice-weekly) could be offered in the school or outside regular school hours. The key is to monitor significant time-bound progress in the child's academic skills and social behavior and confidence.
Accommodation provisions help an older child with: (a) permission to use calculators, (b) extra time to complete the task or test, (c) no deduction of marks for grammar/spelling mistakes, (d) permission to use a writer during examinations, (e) provision for grace marks. Many educational boards provide these provisions to LD children which vary from one State of India to another.
Teaching strategies: Teachers as well as parents need to be adopt the some strategies in class room and at home, as follows-(a) review the information about previous lesson, before beginning a new lesson; (b) clearly state what the student is expected to learn during each lesson; (c) describe how the student is expected to behave during the lesson, e.g. not to talk with peers if the assigned task is found to be difficult, but to raise his/her hands to get the teacher 's attention; (d) state all materials that the child will need during the lesson, e.g. crayons, scissors and colored paper for an art project rather than leaving the child to figure out the need of materials; (e) psycho- educational interventions, e.g. seating the child near the teacher to minimize classroom distractions, etc.
In recent Rights of Persons with Disability Act 2016, LD has been included and recognized as a disability.
Prognosis: Learning disabilities persist throughout life, though it is usually possible to achieve adequate academic skills and school performance with appropriate teaching and learning techniques. The child's social and emotional well-being should also be prioritized.
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