Time reference and tense marking in Greek agrammatism: evidence from narratives and a sentence production priming task.

Cross-linguistic studies on time reference in highly inflected languages have shown that tense inflection is particularly vulnerable in agrammatic speakers. According to the PAstDIscourseLInking Hypothesis (PADILIH), an asymmetry is predicted between past and non-past forms, due to the extra discourse linkage the former type imposes. The present paper investigates whether Greek agrammatic speakers are able to correctly use tense markers with respect to the relevant reference point, analyzing data from three different production tasks to understand how performance is modulated by different methodologies. seven agrammatic speakers and a control group participated in three experimental tasks (a) an elicited picture description, (b) a semi-standardized interview and (c) a sentence production priming task. Different outcomes were elicited across different tasks. Agrammatic speakers tended to accurately use past tense forms when they could freely select the content of their narration, as in the case of the two narrative tasks (the elicited picture description, and the semi-standardized interview). However, the same participants experienced significant difficulties referring to past and future events when using a sentence production priming task. Consequently, the predictions of PADILIH are not fully supported by the Greek data, given that, in addition to past tense deficits, the future tense was also severely compromised. Our data clearly suggest that language performance is affected by the processing demands placed on the patient's linguistic system by the experimental task used. Moreover, future tense deficits in Greek are interpreted as difficulties in the processing of conversational implicatures. [ABSTRACT FROM AUTHOR]