Characterising agrammatism in Standard Indonesian

Background: The spontaneous speech of speakers of Standard Indonesian (SI) with agrammatic Broca's aphasia has not yet been characterised, although there are features of SI that are relevant for the discussion of agrammatic speech.

Aims: The purpose of this study was to find the characteristic features of agrammatism in SI. SI is spoken by about 200 million people and it is important for clinical and rehabilitation purposes to characterise agrammatism in SI.

Methods & Procedures: A total of 21 adults (6 with Broca's aphasia and 15 without history of neurological problems) participated in the study; 300 words of a spontaneous speech sample from each participant underwent syntactic and morphological analyses. The study focused on the defining characteristics of SI agrammatic speech, analysing syntactic and morphological variables.

Outcomes & Results: The study showed that some characteristics of agrammatic speech in Indo-European languages are also found in SI (slower speech rate, shorter MLU, simpler sentence structure, fewer syntactic particles). However, there are also results that are typical for SI agrammatic speech (normal/above normal verb production, overuse of inflectional affixes compared to derivational ones, normal production of sentences with non-canonical word order, such as passives).

Conclusions: For the first time, features of SI agrammatic speech are described. Agrammatic SI can be characterised by a low speech rate and the production of short sentences, just as in other languages. However, several characteristics that have been reported for other languages (e.g., reduced use of verbs) have not been found for SI agrammatic speech, whereas there are agrammatic characteristics in SI that have not been mentioned before for other languages (e.g., reduced number of derivational morphemes, combined with normal number of inflectional morphemes and good access to passive structures). It is argued that this is inherent to the structure of SI. The value of the variables for clinical purposes is discussed.