Unit 3: Definition, types, characteristics and educational needs of children with disabilities

3.1. Mental Illness: Definition and types

3.2. Specific Learning Disabilities / Difficulties: Definition and types

3.3. Deafblindness: Definition and types

3.4. Locomotor Disabilities: Definition and types

3.5. Multiple Disabilities: Definition and types














3.1. Mental Illness: Definition and types

The WHO stress that mental health is “more than just the absence of mental disorders or disabilities.” Peak mental health is about not only avoiding active conditions but also looking after ongoing wellness and happiness.

They also emphasize that preserving and restoring mental health is crucial on an individual basis, as well as throughout different communities and societies the world over.

According to WHO-

Mental disorders comprise a broad range of problems, with different symptoms. However, they are generally characterized by some combination of abnormal thoughts, emotions, behaviour and relationships with others. Examples are schizophrenia, depression, intellectual disabilities and disorders due to drug abuse. Most of these disorders can be successfully treated.

There are many different conditions that are recognized as mental illnesses. The more common types include:


3.2. Specific Learning Disabilities / Difficulties: Definition and types

Learning disabilities (LEARNING DISABILITYs) are real. They affect the brain's ability to receive, process, store, respond to and communicate information. LEARNING DISABILITYs are actually a group of disorders, not a single disorder.

Learning disabilities are not the same as intellectual disabilities (formerly known as mental retardation), sensory impairments (vision or hearing) or autism spectrum disorders. People with LEARNING DISABILITY are of average or above-average intelligence but still struggle to acquire skills that impact their performance in school, at home, in the community and in the workplace. Learning disabilities are lifelong, and the sooner they are recognized and identified, the sooner steps can be taken to circumvent or overcome the challenges they present.


‘Learning disability includes the presence of:

• a significantly reduced ability to understand new or complex information, to learn new skills (impaired intelligence), with;

• a reduced ability to cope independently (impaired social functioning);

• which started before adulthood, with a lasting effect on development.


 A condition of arrested or incomplete development of the mind, which is especially characterised by impairment of skills manifested during the developmental period, which contribute to the overall level of intelligence, i.e. cognitive, language, motor and social abilities.


Specific learning disability refers to heterogeneous clusters of disorders that significantly impede the normal progress of academic achievement in 2%-3% of the school population. The lack of progress is exhibited in school performance that remains below expectation for chronological and mental ages, even when provided with high-quality instruction. The primary manifestation of the failure to progress is significant underachievement in a basic skill area (i.e., reading, math, writing) that is not associated with insufficient educational, interpersonal, cultural/familial, and/or sociolinguistic experiences. The primary severe ability-achievement discrepancy is coincident with deficits in linguistic competence (receptive and/or expressive), cognitive functioning (e.g., problem solving, thinking abilities, maturation), neuropsychological processes (e.g., perception, attention, memory), or any combination of such contributing deficits that are presumed to originate from central nervous system dysfunction. The specific learning disability is a discrete condition differentiated from generalized learning failure by average or above (> 90) cognitive ability and a learning skill profile exhibiting significant scatter indicating areas of strength and weakness. The major specific learning disability may be accompanied by secondary learning difficulties that also may be considered when planning the more intensive, individualized special education instruction directed at the primary problem.

Specific types of learning disabilities and related disorders


Area of difficulty

Symptoms include trouble with



Processing language

·         Reading

·         Writing

·         Spelling

Confusing letter names and sounds, difficulties blending sounds into words, slow rate of reading, trouble remembering after reading text


Math skills

·         Computation

·         Remembering math facts

·         Concepts of time and money

Difficulty learning to count by 2s, 3s, 4s, poor mental math skills, problems with spatial directions


Written expression

·         Handwriting

·         Spelling

·         Composition

Illegible handwriting, difficulty organizing ideas for writing


Fine motor skills

·         Coordination

·         Manual dexterity

Trouble with scissors, buttons, drawing

Information Processing Disorders

Auditory Processing Disorder

Interpreting auditory information

·         Language development

·         Reading

Difficulty anticipating how a speaker will end a sentence

Visual Processing Disorder

Interpreting visual information

·         Reading

·         Writing

·         Math

Difficulty distinguishing letters like “h” and “n”

Other Related Disorders

Attention-Deficit/ Hyperactivity Disorder (ADHD)

Concentration and focus

·         Over-activity

·         Distractibility

·         Impulsivity

Can't sit still, loses interest quickly, daydreams


3.3. Deafblindness: Definition and types

Deafblindness is the combination of significant auditory and visual impairments in a person. These dual sensory losses vary in severity from person to person and do not necessarily lead to total deafness and/or total blindness. It is entirely possible that the person will retain some useful vision and hearing. However, in combination, these impairments of the distant senses causes serious developmental delays in the child, affecting cognitive development, social development, acquisition of communication and language skills, orientation and mobility. A combination of visual and hearing impairment causes such severe developmental, communication and learning needs that the person cannot be educated in special education programs meant for the hearing impaired, for the visually impaired or for severe disabilities. Supplementary assistance would be required to address their unique educational needs consequential to the concurrent impairments of vision and hearing. Deafblindness leads to a severe disabling condition caused by combined losses in hearing and vision. A deafblind child cannot be thought of as blind and also deaf, nor as deaf and also blind. Various terms have been used in the past to refer to this heterogeneous group of population. Earlier, the term ‘deaf blind’ or ‘deaf-blind’ was used. However, keeping with the belief that impairments in both hearing and vision have, not an additive, but a multiplicative effect on the affected individual, the term ‘deafblind’ is now used. Deafblindness is a unique disability; it has its own concepts and terminology, its own methods of assessment and means of education, and its own modes of communication, which distinguishes “deafblindness” from deafness and blindness. Deafblindness is not a medical concept, surprisingly; medical literature makes few references to deafblindness. It is a developmental concept which helps us to understand the nature and the extent of a disability consequent to deafblindness. Because 95 percent of what we learn comes through our eyes and ears, deafblindness leads to difficulties in communication, mobility, and in accessing information.

Deafblind people fall into four groups:

1. Those who are born deaf and blind, which can happen if the mother, inter alia, contacted Rubella (German Measles) during pregnancy.

2. Those who were born deaf and then lost their sight. This is often caused by the Usher Syndrome – deafness followed by a decrease in sight because of retinitis pigmentosa (tunnel vision).

3. Those who were born blind and then lost their hearing.

4. The adventitious deafblind, as a result of old age, or through an illness or accident later in life.

Definition of Deafblindness

“Deafblindness is the condition of having little or no useful sight and hearing. As with the word ‘deaf ’, it can be capitalized to indicate that it is a culture; some prefer the spelling ‘Deafblind’. The most well known deafblind person is the author, activist and lecturer Helen Keller.”

Deaf-blind people have an experience quite distinct from people who are only deaf or blind and not both.

Federal Definition of Deafblindness – USA

“Concomitant hearing and visual impairments, the combination that creates such severe communication and other developmental and educational needs that they cannot be accommodated in special education in programs solely for children with deafness or children with blindness.” FR Dept. of Education

“Deafblindness” is a condition presenting other difficulties than those caused by deafness and blindness. It is an “umbrella” term, which can include both children and adults who are:

Blind and profoundly deaf.

Blind and severely or partially hearing impaired.

Partially sighted and profoundly deaf.

Partially sighted and severely or partially hearing impaired.

“The term, ‘children with deafblindness’, means children and youth having auditory and visual impairments, the combination of which creates such severe communication and other developmental and learning needs that they cannot be appropriately educated without special education and related services, beyond those that would be provided solely for children with hearing impairments, visual impairments, or severe disabilities to address their educational needs due to these concurrent disabilities.”


3.4. Locomotor Disabilities: Definition and types

Strictly speaking Locomotor Disability means problem in moving from one place to another — i.e. disability in legs. But, in general, it is taken as a disability related with bones, joints and muscles. It causes problems in person’s movements (like walking, picking or holding things in hand etc.)

The term Locomotor is derived from the Latin words loco – “from a place” and motivus – “causing motion”. So locomotion means movement from one place to another. And thus locomotor disability hampers movement from one place to another.

A person's inability to execute distinctive activities associated with moving, both personally and objects, from place to place, and such inability resulting from afflictions of musculo-skelatol and, or nervous system, has been defined as the Locomotor Disability Locomotor disability can be classified as: congenital and acquired. The common causes of these two forms of affliction can be classified as: congenital and developmental. Common examples being : cerebral palsy, CTEV, meningocele, meningo myelocele, phocomelias, congenital dislocation of hip. Causes of the acquired disability can be put within the following jackets : Infective and Traumatic. The infective ones are: tuberculosis of spine or other joints, chronic osteomyelitis, septic arthritis, acute poliomyelitis, G.B. syndrome, leprosy, encephalitis, AIDS etc. Traumatic ones are: traffic accidents (air, water, road), domestic accidents, industrial accidents, agricultural accidents, fall from height, bullet injuries, explosions, violence, sports injuries, natural catastrophies like earthquakes, floods etc. Then there can be other causes as well, such as vascular. Common examples are: cerebro vascular disease, peripheral vascular disease, perthe's disease. Neoplastic conditions are yet another cause of locomotor disability. For example, brain tumors like astrocytoma, meningioma, spinal tumors like meningioma, astrocytoma, and osteo sarcoma etc.


Humans are the sole natural reservoir for poliovirus. Infection is transmitted by the oropharyngeal faecal circuit. Poliovims enters the human body through the mouth and alimentary tract. The virus multiplies in the intestines. It then travels to the regional lymph nodes and reticulo endothelial structures. Viremia may occur for a short period. As a result of this, type specific antibodies are produced in the blood and gut. If the immune response is adequate and fast, the virus is neutralized and illness does not occur. If conditions for spread of the virus are present, the virus involves the nervous system. Poliovirus selectively damages some special areas in the nervous system, the most commonly affected area being the anterior horn of the spinal cord. There is no sensory involvement.

Post polio syndrome: Decades after recovering much of their muscle strength, survivors of paralytic polio experience unexpected fatigue, pain and weakness. The cause appear to be degeneration of motor neurons

Cerebral Palsy

Cerebral palsy is a "persistent disorder of movement and posture appearing early in life and due to a developmental non-progressive disorder of the brain." Cerebral palsy is not a disease, nor is it hereditary. Although the abnormality of movement and posture cannot be completely corrected, they may improve as the child's nervous system grows and matures.

There are different types of cerebral palsy. Spastic type is most common and comprises 70% of all patients. Dyskinetic type is present in 10% of all patients, while mixed type (a combination of spastic and dyskinetic types) is present in 20% of all patients. Based on the topographic distribution of neuromotor involvement, classification is also made as (a) quadriplegia (b) diplegia (c) paraplegia (d) hemiplegia (e) triplegia and (f) monoplegia.

Muscular Dystrophies

The muscular dystrophies are a heterogeneous group of inherited disorders with gradual degeneration of the muscle fibres. There are three main types of muscular dystrophies. These are : pseudohypertrophic or duchenne type, fascio scapulo humeral type and limb girdle type.


 The word 'arthritis' literally means joint inflammation. It is characterized by pain, swelling and limitation of joint movement. There are many types of arthritis, such as:

Osteo arthritis (OA): This is the most common type of arthritis. Osteo-arthritis is a degenerative joint disease. It is characterized by loss of joint cartilage and the formation of bony out growths at the edges of the affected joints. Usually one or two of the larger joints are affected. The joints most frequently involved are those of spine, hips and knees. The exact mechanism for loss of cartilage is not known but obesity and stress to the joint contributes to the damage. The likelihood of OA increases with advancing age.

Rheumatoid Arthritis (RA): It is far less common than osteo arthritis but potentially more serious. Rheumatoid Arthritis is a systemic disease. The common symptoms are joint pain, stiffness, fatigue, anorexia, weight loss and fever. Small joints in the hands and feet, wrists, ankles and knees are commonly affected, usually in a fairly symmetric pattern. Subcutaneous nodules may appear over pressure joints (for example, just distal to the elbow). Range of motion of joint is restricted and correctable in early cases. In later stages of the disease, severe restriction with contractures and fixed deformities occur.


 Stroke is characterized by sudden loss of motor control usually hemiplegia i.e. involvement of face, arm and leg of one side. It may be accompanied by unconsciousness, speech disturbance, visual and hearing loss, numbness, burning pain, sensory deficit and psychiatric disturbances. In mild cases of stroke, the manifestation is trivial and does not interfere with the activities of daily living.

Spinal Cord Injury

It is a traumatic insult to the spinal cord that can result in alteration of normal motor, sensory or autonomic functions. It can result in paraplegia i.e. involvement of lower extremities, or quadriplegia i.e. involvement of all extremities. The involvement may be complete or incomplete. The injury is termed incomplete when there is sparing of some sensation, or motor function, or both, distal to the injury. Common causes of spinal injuries are fall from height (root, tree, stairs), motor vehicle accidents, gun shot injury, stab wounds, sports injuries and iatrogenic injuries of cord following surgical procedures.


 Amputation implies the absence of all or part of the limb. Amputations are musculo skeletal problems of a special nature because the disability results not from a pathologic condition, but from treatment that has eliminated the pathologic condition. It can also occur due to congenital skeletal deficiency and trauma. The causes of amputation may be broadly classified as congenital or acquired. Congenital skeletal deficiencies can be transverse or longitudinal. Transverse is defined as absence of all skeletal elements distal to the deficiency. It can further be described as total, upper one third, middle one third, distal one third.

Longitudinal deficiency is an absence extending parallel to the long arm of the limb. The deficiency may be partial or total. Probable causes of congenital skeletal deficiencies are hereditary abnormalities, teratogenic agents, excessive radiation etc.

The causes of acquired limb loss are : accidents, malignant tumors, death of tissue from peripheral vascular insufficiency of atherosclerosis and diabetes, death of tissue due to peripheral vasospastic diseases such as Buergers disease and Raynauds disease, thermal injuries both from heat and cold, long standing infections of bone and other tissues that leave no chance of restoration of function, uselessness of a deformed limb that is objectionable to the patient, neurogenic resorption.


Cancer survivors suffer significant physical and psycho-social problems. They suffer from a range of disabilities related to cancer and the treatment received. Neuromyopathies, pathological fracture, pain, gait problems are not uncommon resulting in significant problems in activities of daily living.


HIV infection primarily attacks the immune system, eventually rendering cell mediated immunity ineffective. This can lead to dysfunction in a number of organ systems. The types of disability that result from HIV disease is virtually identical to that resulting from cancer. The common problems causing disability relate to immobility, central and peripheral nervous system involvement, myopathies, bony involvement, lyrnphoedema, pain and psycho-social illness.

Hansen's Disease

Hansen's disease, which is commonly known as leprosy is a chronic infectious disorder caused by Myco-bacterium eprae. It primarily affects slun, peripheral nerves and other organs e.g. eyes. The cardinal features of Hansen's disease are insensitive skin and paralysis due to involvement of peripheral nerves such as median, ulnar or lateral popliteal nerve. The above defects usually result in unsightly deformities and ulcers in the affected extremities. The common deformities seen are wrist drop, foot drop, claw hand etc. depending on the peripheral nerve involved. The number of cases of Hansen's disease with deformities is quite large in India, although there is a considerable drop in the number of active cases of Hansen's with the advent of multidrug therapy [MDT] .

Tuberculosis [TB] of Bones and Joints

Tuberculous infection of bone occlirs in vertebral bodies or in association with tuberculous infection of joints. It can also occur as an isolated lesion of a long bone or of a bone of the hand or foot. Tubercle bacilli reach the bone either through the blood strem or by direct extension from an adjacent focus in joint or soft tissue.

Tuberculosis of bones and joints usually results in locomotor disability because involvements of joints and causes loss of motion. In the spine, it may result in hunchback or paralysis of limbs, because of involvement of spinal cord.


Lathyrism is a crippling disease caused by consumption of the pulse lathyrus laturis [Kesari dal] is large quantities. Kesari dal is a cheap product and is used to adulterate other dals. The disease is characterised by gradually developing spastic paralysis of the lower limbs. In the early stages of the disease, the patient walks with a slight limp, but as the disease progresses, there is bending of knees with crossing of legs and tendency to walk on toes, and he requires assistance of stick for walking. In advanced cases, the patient is unable to walk and is reduced to crawling.

3.5. Multiple Disabilities: Definition and types

Children who have a combination of severe disabilities are called “Multiply Disabled”. Caring for multiply and severely disabled children is never easy and they need an enormous amount of time, patience and love.

Realising the need for promotion of services for children with multiple disabilities, an autonomous organization of the Ministry of Social Justice and Empowerment, Government of India, was set up under the “National Trust for the Welfare of Persons with Autism, Cerebral Palsy, Mental Retardation and Multiple Disabilities” Act (Act 44 of 1999).The National Trust was set up to find an answer to the worries of parents of such children.

Definition of Multiple Disabilities

Multiple disabilities - “concomitant impairments (such as mental retardation-blindness, mental retardation-orthopedic impairment, etc.) the combination which causes such severe educational needs that they cannot be accommodated in programs solely for one disability. (IDEA)

According to the act “Multiple Disabilities” means a combination of two or more disabilities as defined in clause (i) of section 2 of the Persons with Disabilities (Equal Opportunities, Protection of Rights and Full Participation) Act, 1995 (1 of 1996). Disabilities under the National Trust Act are in fact Developmental Disabilities caused due to insult to the brain and damage to the central nervous system. These disabilities are Autism, Cerebral Palsy, Mental Retardation and Multiple Disabilities. These are neither diseases nor contagious nor progressive. They cannot be cured by drugs or surgery. But early detection and training improve outcome. This is done using the services of Physio-Occupational and Speech Therapists, Community Based Rehabilitation Workers and Special Educators.

The combination of disabilities and degree of severity is different in each child. The time at which the disability occurs in the child, what is known as the ‘age of onset’, may also range from birth to a few days after birth, from early childhood till late teens. Sometimes children are born with one disability but acquire the second or third disabling conditions during childhood. The characteristics and the needs of the children depend on the nature of combination of the disabilities, the age of onset and the opportunities that have been available to a child in his environment.     

Multiple Disability refers to: a combination of two or more disabling conditions that have a combined effect on the child’s communication, mobility and performance of day-to-day tasks.

We can say that just as every child is different, similarly every child with MD is different. However there are some things that this group of children have in common.

·        It affects the all-round development of the child

·        Communication with the world around is most severely affected

·        Opportunities to interact with the environment becomes very limited

·        Ability to move around in the environment is restricted

·        Need regular help in simple day-to-day activities such as wearing a shirt, opening a door,

·        Finding a chair to sit down and so on.

·        A highly structured educational / rehabilitation programme helps in their training.


Some examples of multiple disabilities are:

·         Deafblind (Visual Impairment + Hearing Impairment)

·         Visual Impairment + Hearing Impairment + Mental Retardation

·         Visual Impairment + Mental Retardation

·         Cerebral Palsy + Mental Retardation/ Hearing/ Speech/ Visual problems

Given the numerous disability category combinations possible, the designation multiple disabilities encompasses a broad range of traits. However, the National Dissemination Center for Children with Disabilities (usually referred to as NICHCY) lists several common characteristics, including hampered speech and communication skills, challenges with mobility and a need for assistance in performing everyday activities. It’s also worth noting that medical conditions such as seizures and “water on the brain” (hydrocephalus) can accompany multiple disabilities.