Behavioral and language variants of frontotemporal dementia: a review of key symptoms

While recent advances in the development of neuroimaging and molecular biomarkers for studying neurodegenerative conditions have revolutionized the field, dementia remains a clinical diagnosis. No component of the diagnostic process is more crucial than obtaining a good history. Getting to know the first manifestations of the disease, tracking their evolution and functional impact, combined with a targeted neurological examination, further guides differential diagnosis. This paper summarizes the key symptoms of the behavioral and language variants of frontotemporal dementia. The behavioral variant of frontotemporal dementia (bvFTD) is characterized by severe changes in behavior and personality such as disinhibition, apathy, loss of empathy, or stereotypic behavior, leading to a loss of social competence. Executive functions are impaired, while memory and visuospatial skills are relatively better preserved. By contrast, the language variants or primary progressive aphasias (PPAs) are marked by prominent language disturbances that can be subclassified into a non-fluent/agrammatic variant (naPPA), a semantic variant (svPPA), and a logopenic variant (lvPPA). Although combined characterization of clinical, imaging, biological and genetic biomarkers is essential to establish a detailed diagnosis of such heterogeneous conditions, the author emphasizes the importance of accurate recognition of key symptoms that can lead to better identification of underlying neuropathology and appropriate treatment approaches.