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.
