Transcortical Motor Aphasia

Transcortical Motor Aphasia (TMA or TMoA) is a type of aphasia that is similar to Broca’s aphasia. TMA is due to stroke or brain injury that impacts, but does not directly affect, Broca’s area. Broca’s area is the area of the brain responsible for language production. TMA is the result of a stroke or brain injury that is near Broca’s area. Because of this, Broca’s area can be isolated from other areas of the brain even though it was not directly damaged.

TMA is less common than Broca’s aphasia. People with TMA typically have impairments with spoken language. However, they typically have an easier time with language comprehension.

Transcortical Motor Aphasia is a type of non-fluent aphasia. This means that speech is halting with a lot of starts and stops. People with TMA typically have good repetition skills, especially compared to spontaneous speech. For instance, a person with TMA might be able to repeat a long sentence. However, the same person might be unable to answer the question “Where did you go today?”

Severity can range from mild to severe. Someone with mild TMA might only have difficulties with word-finding and more complex sentence structure. Someone with severe TMA might have little to no verbal speech.

Characteristics of Transcortical Motor Aphasia

Word-finding difficulty (word is “on the tip of the tongue”)
Difficulty with sentence structure and “functor” words, like articles and prepositions
Speech might consist mostly of content words, like nouns and verbs
Speech is slow and halting, and lacks intonation and rhythm
Comprehension might be intact or only mildly impaired
Difficulty with initiating speech
Writing is likely impaired; writing often resembles spoken language