Aphasia has been defined by a number
of people for more than 100 years. I like Goodglass and
Kaplan's definition best. According to Goodglass and Kaplan
(2001, p. 5), "aphasia refers to the disturbance of any or
all of the skills, associations and habits of spoken and
written language produced by injury to certain brain areas
that are specialized for these functions. Disturbances in
communication that are due to paralysis or incoordination of
the musculature of speech or writing or to impaired vision
or hearing are not, of themselves, aphasic." Thus, aphasia
can affect auditory comprehension, oral expression, reading,
writing, and word finding, and can be accompanied by
impaired vision, hearing, muscle weakness and paralysis or
muscle incoordination.
Anomias, Paraphasias, and Executive
Function
Word
Finding Difficulty
According to Keenan (1975), all
aphasics experience some word finding problems.
Anomia seems to affect some
categories of words more than others. Nouns seem to be
especially difficult for aphasic patients to retrieve from
memory while the labels for numbers and letters are often
recalled with relative ease (Goodglass & Kaplan,
1983).
Paraphasia
"Paraphasia refers to the production
of unintended syllables, words, or phrases during the effort
to speak" (Goodglass & Kaplan, 1983, p. 8). Patients
with fluent forms of aphasia exhibit many more paraphasias
than do those with nonfluent types. There are three types of
paraphasias, literal/phonological, neologistic, and semantic/verbal.
Literal/phonological
paraphasia
- More than half of the intended word is produced correctly.
For example, a patient may say /pun/ instead of /spun/. In
addition, transpositions of sounds can occur, e.g "tevilision"
for television. (Brookshire, 1997).
Neologistic
paraphasias - Less than half of the intended
word is produced correctly. In some cases the entire word is
produced incorrectly. Neologisms are also common in the
speech of schizophrenics.
Verbal
paraphasias are those in which another word is
substituted for the target word. (The substitution must be a
real word. If it is not, the paraphasia is classified as
neologistic.)
There are two
types of verbal paraphasias: within category called semantic paraphasias and
remote paraphasias. Within category errors
involve the substitution of a word that is closely related
to the target word, as in cat/dog. Remote errors involve the
substitutions of a word that is only distantly related to
the target word, as in sink/dog. Remote paraphasias are, of
course, indicative of more severe language problems than are
within category substitutions.
Be careful not to
confuse literal interpretations on the part of the patients
with paraphasias. If the patient calls a pencil a "yellow
stick", this does not qualify as a paraphasia. It may mean
that the patient has anomia or even agnosia. Also, the
distorted speech of patients with articulation disorders
like dysarthria should not be mistaken for
neologistic paraphasias.
Paraphasias occur
in the speech of patients with Broca's
aphasia,,
Wernicke's aphasia, and apraxia. (Apraxics usually produce
literal paraphasias.) Wernicke's aphasics have more
paraphasias than Broca's or apraxics.
Executive
Function
The executive
function is a component of cognition. According to Denckla,
1996, it regulates and directs the cognitive process. Injury
to the pre-frontal cortex disrupts the regulation and
initiation of behavior, including language, vocational
behavior, learning/studying behavior, and social behavior,
According to Wehmeyer and Schwartz, 1997 (in Chapey, 2001)
executive functions are similar to the functions involved in
self-determination. Cognitive rehabilitation must include
aspects of executive function.
Emotional
Aspects
After
a stroke, many patients seem to lose some their inhibitions
and may express their emotions to a much greater extent than
they did before their illness. Sometimes, family members
complain that the patient's personality has changed as a
result of the stroke.
Inability to
cope with frustration. Aphasics may have "catastrophic"
reactions to frustration. This is especially true of
patients with Broca's aphasia who tend to be extremely aware
of their deficits.
Emotional
Lability.
Aphasic patients may cry or become angry and swear very
readily. It may be helpful to assure patients that these
displays of emotion are to be expected after a stroke. (Male
patients who are doing a lot of crying may find this
information especially reassuring.) While it is important to
be respectful and sympathetic, it is not necessary to spend
half of a session counseling a patient who cries or yells
every day. In such a case, the speech pathologist should do
his/her best to carry on with therapy or testing.
Rigidity and
Concreteness. Many aphasic patients tend to think
very rigidly and may only grasp the literal interpretations
of language.
Physical Aspects
Most
aphasic patients will have some paralysis and some
hyposthesia or lack or sensation on
the right side. If paralysis is complete, it is called
hemiplegia. Partial paralysis is
referred to as hemiparesis. Generally, the leg will
be less affected by these sensory and motor deficits than
the arm. The principal reason is that the innervation to the
legs is more gross motor than to the arms.
Right
hemianopsia (visual field deficit) is the
disorder of vision that most often accompanies
aphasia.