Aphasia is an impairment of language, affecting the production or comprehension of speech and the
ability to read or write. Aphasia is always due to injury to the brain-most commonly from a stroke,
particularly in older individuals. But brain injuries resulting in aphasia may also arise from head
trauma, from brain tumors, or from infections.
BROCA'S APHASIA
In this form of aphasia, speech output is severely reduced and is limited mainly to short
utterances of less than four words. Vocabulary access is limited and the formation of
sounds by persons with Broca's aphasia is often laborious and clumsy. The person may
understand speech relatively well and be able to read, but be limited in writing. Broca's
aphasia is often referred to as a 'non fluent aphasia' because of the halting and effortful
quality of speech
WERNICK'S APHASIA
In this form of aphasia the ability to grasp the meaning of spoken words
is chiefly impaired, while the ease of producing connected speech is not
much affected. Therefore Wernicke's aphasia is referred to as a 'fluent
aphasia.' However, speech is far from normal. Sentences do not hang
together and irrelevant words intrude-sometimes to the point of jargon,
in severe cases. Reading and writing are often severely impaired.
ANOMIC'S APHASIA
This term is applied to persons who are left with a
persistent inability to supply the words for the very
things they want to talk about-particularly the significant
nouns and verbs. As a result their speech, while fluent in
grammatical form and output is full of vague
circumlocutions and expressions of frustration. They
understand speech well, and in most cases, read
adequately. Difficulty finding words is as evident in
writing as in speech.
OTHER VARIETIES
In addition to the foregoing syndromes that are seen repeatedly
by speech clinicians, there are many other possible combinations
of deficits that do not exactly fit into these categories.Some of the
components of a complex aphasia syndrome may also occur in
isolation. This may be the case for disorders of reading (alexia) or
disorders affecting both reading and writing (alexia and
agraphia), following a stroke. Severe impairments of calculation
often accompany aphasia, yet in some instances patients retain
excellent calculation in spite of the loss of language.