Aphasia is a disorder of speech an language caused by a strategic brain lesion.
Broca’s aphasia is a non-fluent type of aphasia with preserved comprehension caused by a lesion in the dominant (usually left) frontal lobe.
Broca’s affects both speech and writing. Because comprehension is spared, patients can monitor their own speech and become frustrated.
Aphemia is similar to Broca’s aphasia, but is caused by smaller lesions such that affected patients cannot speak but can still communicate with writing: