Language Disorders: Aphasia

Aphasia is a condition that robs you of the ability to communicate. Aphasia is a language disorder caused by damage suffered to certain portions of the brain that are involved in language perception and production. Depending upon the area that is affected, a person suffering from Aphasia may be able to speak fluently but not coherently, and vice versa. It can affect your ability to speak, write and understand language, both verbal and written.

Aphasia typically occurs suddenly after a stroke or a head injury. But it can also come on gradually from a slow-growing brain tumor or a disease that causes progressive, permanent damage (degenerative). The severity of aphasia depends on a number of conditions, including the cause and the extent of the brain damage.

Once the cause has been addressed, the main treatment for aphasia is speech and language therapy. The person with aphasia relearns and practices language skills and learns to use other ways to communicate. Family members often participate in the process, helping the person communicate.

Types of Aphasia

1. Broca's Aphasia

Broca's aphasia, also referred to as 'expressive aphasia’, occurs as a result of damage to the frontal lobe of the brain. As a result of the deletion of function words (i.e. 'and', 'the'), speech by a Broca's aphasic appears telegraphically. As opposed to Wernicke's aphasia, speech is nonfluent, and highly labored depending upon the severity of the aphasia.

2. Global Aphasia

This type of aphasia is a result of extensive damage to the language areas of the brain with the impairments appearing globally across all areas of speech processing and production.

3. Transcortical Motor Aphasia (TMA)

Patients with TMA, also referred to as adynamic aphasia, display nonfluent speech as well as phonemic and global paraphasias and the omission of function words. This aphasia results from damage, typically caused by a stroke, of the anterior superior frontal lobe.

4. Wernicke's Aphasia

Wernicke’s Aphasia occurs as a result of damage to the temporal lobe of the brain. Patients exhibit fluent speech and paraphasias and in some types are unable to comprehend speech as well as produce comprehensible speech.

5. Conduction Aphasia

Conduction aphasia, also referred to as 'associative aphasia', is a fluent disorder caused by damage to the left hemisphere of the brain above and below the posterior sylvian fissure. Auditory comprehension remains fairly intact in these individuals, with speech production being mostly affected. Speech repetition is poor, and spontaneous speech production is labored, with frequent substitution of words or transposing of sounds. As opposed to Wernicke's aphasia, patients with conduction aphasia are often aware of their mistakes and make efforts at correcting their errors.

6. Anomic Aphasia

Anomic aphasia occurs as a result of damage to the language areas outside the perisylvian circle. Characteristic of this aphasia is difficulty in word retrieval, while fluent and well-articulated speech remains intact.

7. Transcortical Sensory Aphasia (TSA)

TSA patients display damage to the temporal occipital parietal junction located behind Wernicke's area. TSA differs from Wernicke's aphasia in that, although they are both fluent disorders, TSA sufferers have fluent and usually comprehensible speech, save for semantic paraphasia in which similar words are substituted for an item. Auditory comprehension is often severely impaired.