Change of Accent as an Atypical Onset of non Fluent Primary Progressive Aphasia

Abstract

Abstract. Language disorders can be the first symptom of many neurodegenerative diseases, including Alzheimer's disease (AD) and primary progressive aphasia (PPA). The main variants of PPA are: the non-fluent/agrammatic variant, the semantic variant and the logopenic variant. Several additional variants of PPA, however, have been described and are considered as atypical presentations. We describe the case of a woman presenting a progressive isolated language disturbance, characterized by an early dysprosodia, phonological and semantic paraphasias, agrammatism, impairment in repetition, writing of non-words and sentence comprehension. This clinical picture pointed to an atypical presentation of the non-fluent variety. The frequent symptom overlap between the different variants of PPA, most likely reflecting differences in the topography of the pathological changes, needs to be considered in the definition of diagnostic criteria.

Neural mechanisms of foreign accent syndrome: Lesion and network analysis

“…Foreign accent syndrome (FAS) is a rare speech disorder, usually caused by neurological disorders, that is characterized by the emergence of a foreign accent. The most common etiology of FAS is stroke, followed by head trauma ( Lippert-Gruener et al, 2005 , Monrad-Krohn, 1947 , Perkins et al, 2010 , Liu et al, 2015 ); metastatic brain tumor ( Abel et al, 2009 ); multiple sclerosis ( Bakker et al, 2004 , Chanson et al, 2009 ); progressive degenerative brain disease, including primary progressive aphasia ( Luzzi et al, 2008 , Paolini et al, 2013 ); learning disorders ( Mariën et al, 2009 , Keulen et al, 2016 ); and psychogenic disorders ( Reeves et al, 2007 , Reeves and Norton, 2001 ). Accent change is thought to result from a combination of segmental deficits, i.e., phonetic distortions and phonemic paraphasias ( Berthier et al, 1991 , Blumstein et al, 1987 , Graff-Radford et al, 1986 , Gurd et al, 1988 , Ingram et al, 1992 , Kurowski et al, 1996 ), and suprasegmental changes, i.e., stress, pitch, and rhythm variation known as dysprosody ( Monrad-Krohn, 1947 , Blumstein et al, 1987 , Ladefoged and Johnson, 2006 , Takayama et al, 1993 ).…”

Loss of regional accent after damage to the speech production network

“…The analysis of changes in production or reception of accents using lesion-symptom mapping is providing fruitful insight on the linguistic, behavioral, and neural mechanisms underpinning the production of foreign and regional accents. These include studies in neurological patients with focal lesions ( Kurowski et al, 1996 ; Blumstein and Kurowsky, 2006 ) or during the early stages of degenerative conditions (Alzheimer’s disease, primary progressive aphasia; Luzzi et al, 2008 ; Hailstone et al, 2012 ; Fletcher et al, 2013 ; Paolini et al, 2013 ).…”