Neuropsycho‐linguistic study of agraphia and aphasia in Moroccan Arabic in patients with Alzheimer’s disease

Abstract

AbstractBackgroundAgraphia and aphasia are common symptoms of neurodegenerative diseases such as Alzheimer’s disease (AD). While most studies were carried out in English, to our knowledge no study has been conducted in Arabic, to characterize these neuro‐psycholinguistic impairments in AD.MethodOur sample included 14 patients (4 with mild and 10 with moderate AD). They met the clinical criteria for AD (McKhann, 2011). The average age is 68.2 years (SD 6; 57‐77). The average number of years of education is 13 years (SD 2.9; 6‐16). The average duration of the disease is 4.2 years (SD 1.97; 1‐8) . The neurolinguistic assessment was used with Mini‐Linguistic State Examination test (MLSE, Patel et al., 2020; Taiebine et al, 2021) for the screening of language disorders. Furthermore, an exhaustive neuropsychological assessment has been carried out (global cognitive functions, memory, attention, verbal fluency, executive, praxis, and visuo‐constructional functions). The writing samples were analyzed using the MMSE sentence writing and MLSE writing subtests.ResultStatistical analysis showed that MLSE scores were influenced by disease severity and duration, whereas education level and age had no effect. As AD progresses, additional impairments become apparent in other cognitive domains. However, the marked syntactic deterioration in MLSE, compared to other linguistic domains, is an atypical pattern, whereas syntax is generally preserved in AD. (Taiebine et al, 2021). Neurolinguistic assessment showed impairment at the macro‐ and micro‐linguistic levels in terms of functional words, verbs, cohesion, and coherence. The analysis of paragraphias showed that the most frequent errors were literal omissions with missing diacritics (36%), followed by graphomotor errors (30%) and allographic errors (10%). The allographic errors are mainly graphemic simplifications that share visuospatial similarities with target letters.ConclusionThis study offers a new perspective on the linguistic characterization of AD. Moreover, it confirms the hierarchical decline in language. The pattern of post‐graphemic disorders found in our patients was consistent with the impairment of peripheral writing buffers in Arabic: graphemic, graphomotor, and allographic.