The 3 Different Types of Primary Progressive Aphasia

Primary Progressive Aphasia, or PPA, is a progressive language disorder resulting from atrophy of the frontal, parietal and temporal regions of the brain, usually on the left side. It is a form of dementia that specifically affects language and speech. A person is said to have PPA if language problems are the most striking symptom this person has at the disease onset. Someone with PPA may experience trouble with language production, ​syntax, object naming, or word comprehension. Speech is the most impaired domain for a PPA patient throughout the course of their diagnosis, though other cognitive functions may become impaired as well with time. It is important to note that an individual does not have PPA if their language problems are the result of other, non-degenerative nervous system or medical disorders, or if their aphasia can improve with time. PPA is, as its name implies, a progressive disease that will worsen with time, and there are three different variants— nonfluent (also called agrammatic), logopedic, and semantic.

The core features of this variant are lack of grammar in speech production and halting or effortful speech. An individual may predominantly have only one of these symptoms and still be diagnosed nonfluent. “Lack of grammar,” in this case, may mean consistent use of short, simple phrases, incorrect sentence structure, or incorrect inflection use. Effortful speech is slow, labored, and lacks the rhythmic quality of normal speech. A person with nonfluent variant may be forced to talk at a very decreased rate due to their difficulty forming sentences or using the muscles necessary to speak what they are thinking. Some patients may describe a feeling of know what they want to say, but being unable to form the words properly with their lips and tongue.

Similar to nonfluent patients, logopenic patients may seem to speak in a halting, slow manner, but these pauses are caused by difficulties with word finding. A person with the logopenic variant will pause in their speech not because they have motor trouble with speaking, but because they simply can’t seem to find the specific word that they would like to say. In fact, the word “logopenia,” derived from Greek, means “lack of words.” Individuals with this type of PPA tend to experience greater general memory impairment than those with other PPA variants. While engaging in small talk, a speech disorder may be hard to detect, but when asked to provide specific words or express answers to more challenging questions, logopenic individuals may struggle. They may take long, unnecessary paths around a gap in their ability to find a word. Normal articulation, however, should be more maintained and speech will not include obvious agrammatic errors.

The notable features of semantic PPA are difficulty recalling the names of everyday objects and lack of word comprehension. For example, someone may be able to have a seemingly normal conversation, and suddenly be treat the word “watermelon” as if it was a foreign language. In addition, people lose the meaning of what the thing actually is—they might be unable, for example, to tell if a watermelon was more like a cantaloupe or an onion. Individuals with this variant may also experience surface dyslexia or dysgraphia (meaning they will write words just like they sound, and read words phonetically as written, e.g. reading “yacht” as “yached”). Despite this, many cognitive abilities can remain intact, such as remembering life events, engaging in complex hobbies, or finding their way around without difficulty.

A relatively rare disease, PPA may begin as a subtle speech disorder. However, as a progressive disease, it will advance with time, and the patient could lose complete ability to read, write, speak, and/or comprehend what they hear. As yet there is no specific drug approved to treat PPA, but management of the disease may include word retrieval practice with a speech therapist or practice using other means of communication, such as through drawing or gestures. Additionally, many people with PPA find it helpful to carry ID cards that can explain their condition to others. Some also find it helpful to connect with others with PPA, and websites that connect international PPA patients can be found online. As the different variants of the disease are caused by different problems within the brain, it is important to understand the differences in variants in order to improve potential treatment methods.