Learning Disabilities.

Aphasia and Dyslexia

Aphasia is the disturbance in formulation and comprehension of language. This class of language disorder ranges from having difficulty remembering words to being completely unable to speak, read, or write. Aphasia is usually linked to brain damage, most commonly by stroke. The brain damage which links aphasia can also cause further brain diseases such as cancer, epilepsy and Alzheimer's disease.

Classifying the different subtypes of aphasia is difficult and has led to disagreements among experts. The localizations model is the original model, but modern anatomical techniques and analyses have shown that precise connections between brain regions and symptom classification do not exist. The neural organization of language is complicated; language is a comprehensive and complex behavior and it makes sense that it is not the product of some small, circumscribed region of the brain.

No classification of patients in subtypes and groups of subtypes is adequate. Only about 60% of patients will fit in a classification scheme such as fluent pure aphasias. There is a huge variation among patients with the same diagnosis, and aphasias can be highly selective. For instance, patients with naming deficits (anomic aphasia) might show an inability only for naming buildings, or people, or colors.

Cognitive neuropsychological model

The cognitive neuropsychological model builds on cognitive neuropsychology. It assumes that language processing can be broken down into a number of modules, each of which has a specific function. Hence there is a module which recognizes phonemes as they are spoken and a module which stores formulated phonemes before they are spoken. Use of this model clinically involves conducting a battery of assessments (usually from the PALPA, the "psycholinguistic assessment of language processing in adult acquired aphasia ... that can be tailored to the investigation of an individual patient's impaired and intact abilities"), each of which tests one or a number of these modules. Once a diagnosis is reached as to where the impairment lies, therapy can proceed to treat the individual module.

Dyslexia is a learning disorder characterized by difficulty reading. Also called specific reading disability, dyslexia is a common learning disability in children. Dyslexia occurs in children with normal vision and intelligence. Sometimes, dyslexia goes undiagnosed for years and isn't recognized until adulthood.

There's no cure for dyslexia. It's a lifelong condition caused by inherited traits that affect how your brain works. However, most children with dyslexia can succeed in school with tutoring or a specialized education program. Emotional support also plays an important role.

Dyslexia symptoms can be difficult to recognize before your child enters school, but some early clues may indicate a problem. Once your child reaches school age, your child's teacher may be first to notice a problem. The condition often becomes apparent as a child begins learning to read.

Before school

Signs and symptoms that a young child may be at risk of dyslexia include:

Late talking

Learning new words slowly

Difficulty rhyming

School age

Once your child is in school, dyslexia signs and symptoms may become more apparent, including:

Reading at a level well below the expected level for the age of your child

Problems processing and understanding what he or she hears

Difficulty comprehending rapid instructions

Trouble following more than one command at a time

Problems remembering the sequence of things

Difficulty seeing (and occasionally hearing) similarities and differences in letters and words

An inability to sound out the pronunciation of an unfamiliar word

Seeing letters or words in reverse ("b" for "d" or "saw" for "was," for example) — this is common in young children, but may be more pronounced in children with dyslexia

Difficulty spelling

Trouble learning a foreign language

Teens and adults

Dyslexia symptoms in teens and adults are similar to those in children. Though early intervention is beneficial for dyslexia treatment, it's never too late to seek help for dyslexia. Some common dyslexia symptoms in teens and adults include:

Difficulty reading

Trouble understanding jokes or idioms

Reading aloud

Difficulty with time management

Difficulty summarizing a story

Difficulty learning a foreign language

Difficulty memorizing

Dyslexia is characterized by a delay in the age at which a child begins to read. Most children are ready to learn reading by kindergarten or first grade, but children with dyslexia often can't grasp the basics of reading by that time. Talk with your doctor if your child's reading level is below what's expected for his or her age or if you notice other signs or symptoms of dyslexia.

When dyslexia goes undiagnosed and untreated, childhood reading difficulties continue into adulthood.