Aphasia
Is an impairment of language ability. This class oflanguage disorder ranges from having difficulty remembering words to being completely unable to speak, read, or write.
Aphasia disorders usually develop quickly as a result ofhead injury or stroke, but can develop slowly from a brain tumor,infection, ordementina, or can be a learning disability such asdysomia.
The area and extent of brain damage determine the type of aphasia and its symptoms. Aphasia types include ,non fluent aphasia,motor aphasia,expressive aphasia,receptive aphasia,global aphasia and many others.
Medical evaluations for the disorder range from clinical screenings by aneuologist to extensive tests by a speech-language Pathology.
Most aphasia patients can recover some or most skills by working with a Speech-Language Pathologist. This rehabilitation can take two or more years and is most effective when begun quickly. Only a small minority will recover without therapy, such as those suffering a mini-stroke. Patients with a learning-disorder aphasia such as dysnomia can learn coping skills, but cannot recover abilities that are congenitally limited.
Improvement varies widely, depending on the aphasia's cause, type, and severity. Recovery also depends on the patient's age, health, motivation,handedness, and educational level.
Damage to a region of the motor association cortex in the left frontal lobe (Broca's area) disrupts the ability to speak. It causes Broca's aphasia, a language disorder characterized by slow, laborious, non-fluent speech.


Dyslexia
 Is a very broad term defining alearning disability that impairs a person's fluency or comprehension accuracy in being able to read, and which can manifest itself as a difficulty withphonologycal awareness,phonologycal decoding,orthograhic coding,auditory short-term memory, orrapid naming. Dyslexia is separate and distinct from reading difficulties resulting from other causes, such as a non-neurological deficiency with vision or hearing, or from poor or inadequate reading instruction. It is believed that dyslexia can affect between 5 and 10 percent of a given population although there have been no studies to indicate an accurate percentage.