Primary progressive aphasia (PPA) is a neurological condition that causes an individual's language capabilities to become progressively more impaired. Most forms of aphasia are caused by brain injury or stroke, but primary progressive aphasia is related to neurodegenerative illness. It's seen with diseases like frontotemporal lobar degeneration and Alzheimer's disease. The condition occurs when brain tissue related to language and speech deteriorates. The presentation varies between patients, but there are some characteristic signs of the condition.
Difficulty Comprehending Language
Individuals with primary progressive aphasia may have difficulty comprehending language. This symptom occurs when the semantic portion of the brain is affected. In the semantic variety of PPA, patients may have trouble comprehending written or spoken language. It's especially difficult to comprehend or remember the meanings of singular words. In addition to having trouble remembering the definition of a written or spoken word, individuals with this condition may have trouble remembering the names of objects or words to describe them.
It's important to note there are three kinds of primary progressive aphasia, with semantic being just one. If multiple language-processing areas of the brain are affected, patients might have symptoms of multiple types. But a difficulty with language comprehension doesn't present in every patient with this condition.
Difficulty Finding Words
Primary progressive aphasia patients may have difficulty finding words. This symptom is most common in those with the logopenic variant. It may be hard for affected individuals to retrieve words from the brain and communicate. Patients often have trouble finding word substitutions like synonyms and antonyms. When patients speak out loud, they tend to have frequent pauses as they try to find the right words. Individuals with PPA may also have trouble with repeating sentences or phrases spoken to them. Unlike the semantic variety, these symptoms aren't about word associations. Instead, they're about the ability to communicate with any words at all.
Apraxia Of Speech
Apraxia of speech may be an indicator of a problem with the language center of the brain. Progressive apraxia of speech is a neurodegenerative condition, similar to primary progressive aphasia, though apraxia of speech is a different condition. It is important to note, however, the two might occur together. With apraxia of speech, patients have trouble producing sounds properly.
The disorder affects the programming or motor planning of speech, which causes an individual to make improperly pronounced words and syllables. As the disease progresses, patients lose more of their ability to manufacture speech. Some patients become totally mute. The main difference between apraxia of speech and PPA is that the former is caused by a failure to form words properly, while the latter is related to the use of words.
Some memory loss symptoms are associated with primary progressive aphasia itself. When the language centers in the brain degenerate, patients may forget words or their associations. They might have trouble naming familiar objects or individuals. It's common for the underlying cause of PPA to be Alzheimer's disease. When the abnormal proteins manufactured by Alzheimer's disease attack the brain's language centers, the result is a form of primary progressive aphasia. Alzheimer's disease causes thirty to forty percent of cases.
In addition, Alzheimer's disease is responsible for frontotemporal lobar degeneration in around sixty to seventy percent of patients. PPA is also sometimes caused by an atypical presentation of Alzheimer's disease. When Alzheimer's disease is the underlying cause, patients will experience memory loss and other symptoms related to that disease. Memory loss also occurs when the underlying cause attacks the memory portion of the brain.
Loss Of Speech
Loss of speech may occur as primary progressive aphasia progresses. The condition continues to progress until the language centers in the brain are irreparably damaged. With semantic PPA, patients lose their understanding of words and their definitions over time. In progressive non-fluent aphasia, affected individuals may need to make more effort with speech. They may use an incorrect word or incorrect grammar because their understanding of language structure is impaired.
With logopenic aphasia, patients may have to pause when they speak to find the right word. The progression of logopenic aphasia can result in patients losing their ability to speak entirely. There are also cases where apraxia occurs alongside the aphasia. Apraxia damages an individual's ability to form and pronounce words, even if they can retrieve the word they want. Apraxia patients sometimes become completely mute. The combination of aphasia and apraxia may be more likely to lead to muteness than apraxia or aphasia alone.