The Facts about Learning Disabilities

Learning disabilities (LD) are disorders that affect the ability to understand or use spoken or written language, do mathematical calculations, coordinate movements or direct attention. Although learning disabilities occur in very young children, the disorders are usually not recognized until the child reaches school age.

LDs affect people's ability to either interpret what they see and hear, or to link information from different parts of the brain. These limitations can show up in many ways - as specific difficulties with spoken and written language, coordination, self-control or attention. Such difficulties extend to schoolwork and can interfere with learning to read, write, or do math.

"Learning disability" is not a diagnosis in the same sense as "chickenpox" or "mumps." Chickenpox and mumps imply a single, known cause with a predictable set of symptoms. Rather, LD is a broad term that covers many possible causes, symptoms, treatments and outcomes. Some people may have a single, isolated learning problem that has little impact on their lives, while others may show several overlapping learning disabilities. Partly because learning disabilities can show up in so many forms, it is difficult to diagnose or to pinpoint the causes.

The most common treatment for learning disabilities is special education. Specially trained educators may perform a diagnostic educational evaluation assessing the child's academic and intellectual potential and level of academic performance. Once the evaluation is complete, the basic approach is to teach learning skills by building on the child's abilities and strengths while correcting and compensating for disabilities and weaknesses. Other professionals such as speech and language therapists also may be involved. Some medications may be effective in helping the child learn by enhancing attention and concentration. Psychological therapies may also be used.

Learning disabilities can be lifelong conditions. LDs can make it difficult or impossible for people to communicate important needs and ideas or to focus their attention. Some people with LDs may feel overwhelmed by sights and sounds, or be unable to make sense of letters or numbers.

Although different from person to person, these difficulties make up the common daily experiences of many learning disabled children, adolescents, and adults. A person with a learning disability may experience a cycle of academic failure and lowered self-esteem. Having these handicaps, or living with someone who has them, can cause enormous frustration.

Not all learning problems are necessarily learning disabilities. Many children are simply slower in developing certain skills. Because children show natural differences in their rate of development, sometimes what seems to be a learning disability may simply be a delay in maturing. To be diagnosed as a learning disability, specific criteria must be met.

The "Hidden Handicap"
Unlike other disabilities such as paralysis or blindness, a learning disability is a hidden handicap. A learning disability doesn't disfigure or leave visible signs that would invite others to be understanding or offer support.

The criteria and characteristics for diagnosing learning disabilities appear in a reference book called the Diagnostic and Statistical Manual of Mental Disorders (DSM). The DSM diagnosis is commonly used when applying for health insurance coverage of diagnostic and treatment services.

The Three Faces of Learning Disabilities
Learning disabilities can be divided into three broad categories: developmental speech and language disorders; academic skills disorders; and "Other," a catch-all that includes certain coordination disorders and learning handicaps not covered by the other terms. Each of these categories includes a number of more specific disorders.

Developmental Speech and Language Disorders
Speech and language problems are often the earliest indicators of a learning disability. People with developmental speech and language disorders have difficulty producing speech sounds, using spoken language to communicate, or understanding what other people say. Depending on the problem, the specific diagnosis might be one of the following:

Developmental articulation disorder. Children with this disorder might have trouble controlling their rate of speech, or lag behind playmates in learning to make speech sounds. For example, at age 6 a child with this disorder might still say "wabbit" instead of "rabbit" or "thwim" for "swim." Developmental articulation disorders are common. They appear in at least 10% of children younger than age 8. Fortunately, articulation disorders can often be outgrown or successfully treated with speech therapy.

Developmental expressive language disorder.Children with this type of language impairment have problems expressing themselves in speech. For instance, a child with this disorder might call objects by the wrong names. Expressive language disorders can also take other forms. A 4-year-old who speaks only in two-word phrases and a 6-year-old who can't answer simple questions are also likely to have an expressive language disability.

Developmental receptive language disorder. People with this category of disorder have trouble understanding certain aspects of speech. There's the toddler who doesn't respond to his name, the preschooler who hands you a bell when you asked for a ball, or the worker who consistently can't follow simple directions. Their hearing is fine, but they can't make sense of certain sounds, words, or sentences they hear. It might seem like they're not paying attention. These people have a receptive language disorder. Because using and understanding speech are strongly related, many people with receptive language disorders also have an expressive language disability. Of course, in preschoolers some misuse of sounds, words, or grammar is a normal part of learning to speak. It's only when these problems persist that there is any cause for concern.

Academic Skills Disorders
Students with academic skills disorders are often years behind their classmates in developing reading, writing, or arithmetic skills. The diagnoses in this category include:

Developmental reading disorder. This type of disorder, also known as dyslexia, is quite widespread. In fact, reading disabilities affect 2% to 8% of elementary school children.

Reading requires simultaneous use of a complex set of skills, including:

• Focusing attention on printed marks and controlling eye movements across the page.
• Recognizing the sounds associated with letters.
• Understanding words and grammar.
• Building ideas and images.
• Comparing new ideas to what you already know.
• Storing ideas in memory.

The fact that most of us can perform all these tasks at the same time is remarkable. Such mental juggling requires a rich, intact network of nerve cells that connect the brain's centers of vision, language and memory.

A person can have problems in any of the tasks involved in reading. However, scientists found that a significant number of people with dyslexia share an inability to distinguish or separate the sounds in spoken words. For example, one child with dyslexia might be unable to identify the word "bat" by sounding out the individual letters, b-a-t. Another child with dyslexia might have trouble with rhyming games, such as rhyming the two words "cat" and "bat." Scientists have found these skills fundamental to learning to read. Fortunately, remedial reading specialists have developed techniques that can help many children with dyslexia acquire these skills.

But there is more to reading than recognizing words. If the brain is unable to form images or relate new ideas to those stored in memory, the reader can't understand or remember the new concepts. So other types of reading disabilities can appear in the upper grades when the focus of reading shifts from word identification to comprehension.

Developmental writing disorder. Writing, too, involves several brain areas and functions. The brain networks for vocabulary, grammar, hand movement, and memory must all be in good working order. So a developmental writing disorder may result from problems in any of these areas. For example, a child who is unable to distinguish the sequence of sounds in a word will likely have problems with spelling. A child with a writing disability might be unable to compose complete, grammatical sentences.

Developmental arithmetic disorder. Arithmetic is a complex process. It involves recognizing numbers and symbols, memorizing facts such as the multiplication table, aligning numbers, and understanding abstract concepts like place value and fractions. Any of these can be difficult for children with developmental arithmetic disorders. Problems with numbers or basic concepts are likely to show up early. Disabilities that appear in the later grades are more often tied to problems in reasoning.

Since many aspects of speaking, listening, reading, writing and arithmetic overlap and build on the same brain capabilities, it's not surprising that people can be diagnosed as having more than one area of learning disability. For example, the ability to understand language underlies learning to speak. Therefore, any disorder that interferes with the ability to understand language will also interfere with the development of speech, which in turn gets in the way of learning to read and write. A single gap in the brain's operation can disrupt many types of activity.

"Other" Learning Disabilities
The DSM also lists additional categories, such as "motor skills disorders" and "specific developmental disorders not otherwise specified." These diagnoses include delays in acquiring language, academic and motor skills that can affect the ability to learn, but do not meet the criteria for a specific learning disability. Also included are coordination disorders that can lead to poor penmanship, as well as certain spelling and memory disorders.

Attention Disorders
Attention disorders, with or without hyperactivity, are not considered learning disabilities in themselves. However, because attention problems can seriously interfere with school performance, they often accompany academic skills disorders.

In a large proportion of affected children - mostly boys - the attention deficit is accompanied by hyperactivity. Children with attention deficit hyperactivity disorder, or ADHD, act impulsively and can't sit still. They blurt out answers and interrupt. In games, they can't wait their turn. These children's problems are usually hard to miss. Because of their constant motion and explosive energy, hyperactive children often get into trouble with parents, teachers and peers. For example, they might run into traffic or topple desks, or jump up and down to exhaustion.

Of the nearly 4 million school-age children with learning disabilities, at least 20% also have syndromes that leave them unable to focus their attention. Some children and adults who have attention disorders appear to daydream excessively. Even when they are able to pay attention, they're easily distracted. Some may have a number of learning difficulties, but if they are quiet and don't cause trouble, their problems may go unnoticed. They may be passed along from grade to grade without getting the special assistance they need.

Learning disabilities can be lifelong conditions that, in some cases, affect many parts of a person's life: school or work, daily routines, family life, and sometimes even friendships and play. In some people, many overlapping learning disabilities are apparent. Others may have a single, isolated learning problem that has little impact on other areas of their lives. But the prospects are hopeful. It is important to remember that a person with a learning disability can learn. The disability usually only affects certain limited areas of development. In fact, learning disabilities are rarely severe enough to impair a person's potential to live a happy, normal life.

This article was adapted from Learning Disabilities, provided by the National Institutes of Health.

For more information on these topics, see the HealthLink articles Diagnosing Learning Disabilities, Understanding Brain Function in Dyslexia and One in Every Classroom: Kids With ADHD Struggle to Make the Grade.