Progressive nonfluent aphasia (PNFA) is one of three clinical syndromes associated with

frontotemporal lobar degeneration Frontotemporal lobar degeneration (FTLD) is a pathological process that occurs in frontotemporal dementia. It is characterized by atrophy in the frontal lobe and temporal lobe of the brain, with sparing of the parietal and occipital lobes. Commo ...

. PNFA has an insidious onset of language deficits over time as opposed to other stroke-based aphasias, which occur acutely following trauma to the brain. The specific degeneration of the

frontal Front may refer to: Arts, entertainment, and media Films * ''The Front'' (1943 film), a 1943 Soviet drama film * ''The Front'', 1976 film Music *The Front (band), an American rock band signed to Columbia Records and active in the 1980s and ea ...

and

temporal lobe The temporal lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The temporal lobe is located beneath the lateral fissure on both cerebral hemispheres of the mammalian brain. The temporal lobe is involved in proc ...

s in PNFA creates hallmark language deficits differentiating this disorder from other

Alzheimer Alzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As t ...

-type disorders by the initial absence of other cognitive and memory deficits. This disorder commonly has a primary effect on the

left hemisphere The lateralization of brain function is the tendency for some neural functions or cognitive processes to be specialized to one side of the brain or the other. The median longitudinal fissure separates the human brain into two distinct cerebr ...

, causing the symptomatic display of expressive language deficits (production difficulties) and sometimes may disrupt receptive abilities in comprehending grammatically complex language.

Presentation

The main clinical features are signature language progressive difficulties with speech production. There can be problems in different parts of the speech production system, hence patients can present with articulatory breakdown, phonemic breakdown (difficulties with sounds) and other problems. However, it is rare for patients to have just one of these problems and most people will present with more than one problem. Features include: * Hesitant, effortful speech *

Apraxia of speech Apraxia of speech (AOS), also called verbal apraxia, is a speech sound disorder affecting an individual's ability to translate conscious speech plans into motor plans, which results in limited and difficult speech ability. By the definition of ...

Stutter Stuttering, also known as stammering, is a speech disorder in which the flow of speech is disrupted by involuntary repetitions and prolongations of sounds, syllables, words, or phrases as well as involuntary silent pauses or blocks in which the ...

(including return of a childhood stutter) * Anomia * Phonemic

paraphasia Paraphasia is a type of language output error commonly associated with aphasia, and characterized by the production of unintended syllables, words, or phrases during the effort to speak. Paraphasic errors are most common in patients with fluent for ...

(sound errors in speech e.g. 'gat' for 'cat') *

Agrammatism Agrammatism is a characteristic of non-fluent aphasia. Individuals with agrammatism present with speech that is characterized by containing mainly content words, with a lack of function words. For example, when asked to describe a picture of ch ...

(using the wrong tense or word order) As the disease develops, speech quantity decreases and many patients become mute. Cognitive domains other than language are rarely affected early on. However, as the disease progresses, other domains can be affected. Problems with writing, reading, and speech comprehension can occur, as can behavioural features similar to

frontotemporal dementia Frontotemporal dementia (FTD), or frontotemporal degeneration disease, or frontotemporal neurocognitive disorder, encompasses several types of dementia involving the progressive degeneration of frontal and temporal lobes. FTDs broadly present a ...

Diagnosis

Imaging studies have shown differing results which probably represents the heterogeneity of language problems than can occur in PNFA. However, classically atrophy of left perisylvian areas is seen. Comprehensive meta-analyses on MRI and FDG-PET studies identified alterations in the whole left frontotemporal network for phonological and syntactical processing as the most consistent finding. Based on these imaging methods, progressive nonfluent aphasia can be regionally dissociated from the other subtypes of

, frontotemporal dementia and semantic dementia.

Classification

Some confusion exists in the terminology used by different neurologists. Mesulam's original description in 1982 of progressive language problems caused by neurodegenerative disease (which he called primary progressive aphasia (PPA) included patients with progressive nonfluent (aphasia,

semantic dementia Semantic dementia (SD), also known as semantic variant primary progressive aphasia (svPPA), is a progressive neurodegenerative disorder characterized by loss of semantic memory in both the verbal and non-verbal domains. However, the most common p ...

, and

logopenic progressive aphasia Logopenic progressive aphasia (LPA) is a variant of primary progressive aphasia. It is defined clinically by impairments in naming and sentence repetition. It is similar to conduction aphasia and is associated with atrophy to the left posterior te ...

Management

No cure or treatment for this condition has been found. Supportive management is helpful.

Presentation

Diagnosis

Classification

Management

See also

References

Further reading