Eye-tracking the effect of word order in sentence comprehension in aphasia: evidence from Basque, a free word order ergative language

Abstract

Agrammatic speakers of languages with overt grammatical case show impaired use of the morphological cues to establish theta-role relations in sentences presented in non-canonical word orders. We analysed the effect of word order on the sentence comprehension of aphasic speakers of Basque, an ergative, free word order and head-final (SOV) language. Ergative languages such as Basque establish a one-to-one mapping of the thematic role and the case marker. We collected behavioural and gaze-fixation data while agrammatic speakers performed a picture-matching task with auditorily presented sentences with different word orders. We found that people with aphasia (PWA) had difficulties in assigning theta-roles in Theme-Agent order. This result is in line with processing accounts. Contrary to previous findings, our data do not suggest a systematic delay in the integration of morphological information in the PWA group, but strong reliance on the ergative case morphology and difficulties assigning thematic roles into the determiner phrases.

What happens when they think they are right? Error awareness analysis of sentence comprehension deficits in aphasia

“…In contrast, in the incorrectly answered trials, PWA showed a completely different gaze-fixation pattern, characterised by a progressive proportion of fixations towards the foil picture. Similar results have been reported in subsequent studies combining VWP with a sentence-picture matching task in English (Dickey & Thompson, 2009), German (Hanne, Sekerina, Vasishth, Burchert, & De Bleser, 2011;Schumacher et al, 2015), and Basque (Arantzeta et al, 2017) PWA. Altogether, evidence from online data does not support the existence of a guessing pattern in sentence processing in PWA, but distinctive parsing routines that determine the interpretation of the sentence.…”

“…The materials used in this study were adapted to standard European Spanish from the experiment presented by Arantzeta et al (2017). They consisted of single sentences provided auditorily in combination with the presentation of two pictures on the screen.…”

“…The same 22 transitive verbs used in the original study (Arantzeta et al, 2017) as well as two animate singular DPs assigned to each verb were selected to create declarative sentences in the following structures: (a) active; (b) passive; (c) subject relative; (d) object relative; (e) subject cleft; (f) object cleft. Subsequently, sentence conditions were clustered as Agent-Theme (A-T) and Theme-Agent (T-A) for data analysis.…”

“…The 44 black-and-white line drawings used by Arantzeta et al (2017) were adapted for the current study. The drawings constituted 22 pairs, which were presented together divided by a black vertical line in the middle of the screen.…”

“…However, deficits in comprehending sentence in T-A argument order have been found in PWA speakers of languages with more rigid word order (i.e., in English, Meyer, Mack, & Thompson, 2012;Schwartz, Saffran, & Marin, 1980;in Dutch, Bastiaanse & Edwards, 2004), flexible word order (i.e., in Spanish, Juncós-Rabadán, Pereiro, & Souto, 2009; in German, Burchert, De Bleser, & Sonntag, 2003;in Italian, Garraffa & Grillo, 2008;in Turkish, Duman, Altinok, Özgirgin, & Bastiaanse, 2011;in Swahili, Abuom, Shah, & Bastiaanse, 2013;cf. in Indonesian, Jap, Martínez-Ferreiro, & Bastiaanse, 2016), and free word order (i.e., in Basque, Arantzeta et al, 2017).…”