Effects of language-specific structure on agrammatism lessons from Greenlandic

Agrammatism is a type of non-fluent aphasia characterised by difficulties with grammatical elements. The syndrome has primarily been described in Indo European languages, whose structures are rather similar. Therefore, only little is known about the crosslinguistic variation in symptoms of agrammatism and how structural features of individual languages influence this variation. To investigate effects of language-specific structure on the symptoms of agrammatism, this thesis presents a description of agrammatism in Greenlandic, a language that, unlike Indo-European languages, is highly synthetic.

Two findings stand out: 1) the participants with agrammatism use many verbs and 2) their difficulties with suffixes are relatively limited. Both findings are surprising given that studies in other languages often link agrammatism to sparse use of verbs and pronounced difficulties with suffixes.

However, the Greenlandic findings can be explained with reference to the structure of the language: verbs are the only obligatory part of clauses, and most roots are bound, meaning that inflection is a precondition for using them. Regarding the use of optional suffixes, the thesis proposes that many of them have lexical rather than grammatical status in Greenlandic and are therefore not directly affected by the grammatical difficulties that characterise agrammatism. To test this proposal, the thesis provides a crosslinguistic definition of lexical affixes as potentially prominent and modifiable. Suffixes identified as lexical according to the definition cannot, however, immediately account for the use of optional suffixes by the participants with agrammatism. Nevertheless, the definition of lexical affixes constitutes a contribution to the description of Greenlandic and other synthetic languages.

By comparing the observations in Greenlandic to observations in other languages, the thesis argues that symptoms of agrammatism pertaining to structural linguistic categories, such as sparse use of verbs, cannot be assumed to be universal. This insight is crucial for attaining a crosslinguistically adequate understanding of agrammatism, and it is relevant for clinicians working with less-studied languages because it implies that they should not necessarily look for or treat the features that have proven relevant in more well-studied languages.