Patterns of Language Impairment in Early Amyotrophic Lateral Sclerosis

Abstract

Objective.To investigate the incidence and nature of language change and its relationship to executive dysfunction in a population-based incident ALS sample, with the hypothesis that patterns of frontotemporal involvement in early ALS extend beyond areas of executive control to regions associated with language processing.Methods.One hundred and seventeen population-based incident ALS cases without dementia and 100 controls matched by age, sex and education were included in the study. A detailed assessment of language processing including lexical processing, word spelling, word reading, word naming, semantic processing and syntactic/grammatical processing was undertaken. Executive domains of phonemic verbal fluency, working memory, problem-solving, cognitive flexibility and social cognition were also evaluated.Results.Language processing was impaired in this incident cohort of individuals with ALS, with deficits in the domains of word naming, orthographic processing and syntactic/grammatical processing. Conversely, phonological lexical processing and semantic processing were spared. While executive dysfunction accounted in part for impairments in grammatical and orthographic lexical processing, word spelling, reading and naming, primary language deficits were also present.Conclusions.Language impairment is characteristic of ALS at early stages of the disease, and can develop independently of executive dysfunction, reflecting selective patterns of frontotemporal involvement at disease onset. Language change is therefore an important component of the frontotemporal syndrome associated with ALS.

Prevalence and determinants of language impairment in non‐demented amyotrophic lateral sclerosis patients

“…Even in the face of the abovementioned considerations on the potential biases of the ECAS‐Language, and consistently with earlier reports [ 8 , 9 ], this work appears to confirm that attention and executive functioning are strong determinants of language in non‐demented ALS patients—also showing that dysexecutive features are associated with LI in this population. Nevertheless, a notable amount of variance (i.e., 46.6%) in ECAS‐Language scores could not be accounted for by either executive performances or other variables, this supporting the previously acknowledged notion of LI being primary, at least to an extent, in this population [ 8 , 9 ] and not merely secondary to executive dysfunction [ 2 , 3 , 4 ].…”

“…Relatedly, such findings might not be fully generalizable to languages other than Italian: for instance, a recent report comparing Italian to English patients with progressive non‐fluent aphasia—which is a condition pathophysiologically and genetically related to ALS [ 11 ]—has shown between‐language differences in speech praxis and morpho‐syntactic processing [ 43 ]. At the same time, it is worth stressing that, as previously mentioned, the prevalence estimate given here is similar overall to those recently reported in non‐demented ALS patients speaking other languages, that is, English [ 9 ] and German [ 25 ].…”

“…Findings reported here suggest that up to ≈23% of non‐demented ALS patients can present with impairments of language functioning, as assessed by the dedicated ECAS subscale. Despite being lower than the currently accepted estimate (≈35%–40%) [1,7,8], the present estimate aligns to those yielded by recent, and up‐to‐now largest‐sized, studies assessing language in non‐demented ALS patients via either a second‐level battery ( N = 117) [9] (i.e., up to 23%) or the ECAS‐Language itself ( N = 215) (i.e., 25%) [25].…”

“…Indeed, the currently accepted prevalence estimate of LI in non‐demented ALS patients (i.e., ≈35%–40%) [ 1 , 7 ] relies on the 2013 pioneering study by Taylor et al [ 8 ], which, however, (i) addressed a relatively small sample size ( N = 50) and (ii) did not include ALS‐specific language measures. Furthermore, motor and non‐motor determinants of LI in this population have been only partially explored to this day, outside of its association with dysexecutive features [ 8 , 9 ] and bulbar involvement [ 10 , 11 ].…”

Language impairment in sporadic and familial (type 8) amyotrophic lateral sclerosis: A comparative study

“…[2][3][4] Behavioral symptoms, such as apathy, are also observed. 4,5 Language is frequently affected in sporadic ALS (sALS), 6,7 with reduced performance in naming tests, as well as in tasks assessing semantics in the comprehension of isolated words or sentences, 8 in syntactic comprehension and expression with failures in the use and interpretation of essential syntactic elements for the construction and adequate understanding of sentences, 7,9,10 and orthographic processing by duplicating, omitting or substituting graphemes in regular words or making regularizations in irregular words. 7 The ability to organize narrative discourse is also impaired, 11 characterized by discourse inadequacy, connectedness failures, and difficulty in maintaining a narrative theme.…”