@article{ArantzetaBastiaanseBurchertetal.2017, author = {Arantzeta, Miren and Bastiaanse, Roelien and Burchert, Frank and Wieling, Martijn Benjamin and Martinez-Zabaleta, Maite and Laka, Itziar}, title = {Eye-tracking the effect of word order in sentence comprehension in aphasia}, series = {Language, cognition and neuroscience}, volume = {32}, journal = {Language, cognition and neuroscience}, number = {10}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {2327-3798}, doi = {10.1080/23273798.2017.1344715}, pages = {1320 -- 1343}, year = {2017}, 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.}, language = {en} } @article{AdeltStadieLassottaetal.2017, author = {Adelt, Anne and Stadie, Nicole and Lassotta, Romy and Adani, Flavia and Burchert, Frank}, title = {Feature dissimilarities in the processing of German relative clauses in aphasia}, series = {Journal of neurolinguistics : an international journal for the study of brain function in language behavior and experience}, volume = {44}, journal = {Journal of neurolinguistics : an international journal for the study of brain function in language behavior and experience}, publisher = {Elsevier}, address = {Oxford}, issn = {0911-6044}, doi = {10.1016/j.jneuroling.2017.01.002}, pages = {17 -- 37}, year = {2017}, abstract = {The cross-linguistic finding of greater demands in processing object relatives as compared to subject relatives in individuals with aphasia and non-brain-damaged speakers has been explained within the Relativized Minimality approach. Based on this account, the asymmetry is attributed to an element intervening between the moved element and its extraction site in object relatives, but not in subject relatives. Moreover, it has been proposed that processing of object relatives is facilitated if the intervening and the moved elements differ in their internal feature structure. The present study investigates these predictions in German-speaking individuals with aphasia and a group of control participants by combining the visual world eye-tracking methodology with an auditory referent identification task. Our results provide support for the Relativized Minimality approach. Particularly, the degree of featural distinctness was shown to modulate the occurrence of the effects in aphasia. We claim that, due to reduced processing capacities, individuals with aphasia need a higher degree of featural dissimilarity to distinguish the moved from the intervening element in object relatives to overcome their syntactic deficit. (C) 2017 Elsevier Ltd. All rights reserved.}, language = {en} } @article{MaetzigVasishthEngelmannetal.2018, author = {M{\"a}tzig, Paul and Vasishth, Shravan and Engelmann, Felix and Caplan, David and Burchert, Frank}, title = {A computational investigation of sources of variability in sentence comprehension difficulty in aphasia}, series = {Topics in cognitive science}, volume = {10}, journal = {Topics in cognitive science}, number = {1}, publisher = {Wiley}, address = {Hoboken}, issn = {1756-8757}, doi = {10.1111/tops.12323}, pages = {161 -- 174}, year = {2018}, abstract = {We present a computational evaluation of three hypotheses about sources of deficit in sentence comprehension in aphasia: slowed processing, intermittent deficiency, and resource reduction. The ACT-R based Lewis and Vasishth (2005) model is used to implement these three proposals. Slowed processing is implemented as slowed execution time of parse steps; intermittent deficiency as increased random noise in activation of elements in memory; and resource reduction as reduced spreading activation. As data, we considered subject vs. object relative sentences, presented in a self-paced listening modality to 56 individuals with aphasia (IWA) and 46 matched controls. The participants heard the sentences and carried out a picture verification task to decide on an interpretation of the sentence. These response accuracies are used to identify the best parameters (for each participant) that correspond to the three hypotheses mentioned above. We show that controls have more tightly clustered (less variable) parameter values than IWA; specifically, compared to controls, among IWA there are more individuals with slow parsing times, high noise, and low spreading activation. We find that (a) individual IWA show differential amounts of deficit along the three dimensions of slowed processing, intermittent deficiency, and resource reduction, (b) overall, there is evidence for all three sources of deficit playing a role, and (c) IWA have a more variable range of parameter values than controls. An important implication is that it may be meaningless to talk about sources of deficit with respect to an abstract verage IWA; the focus should be on the individual's differential degrees of deficit along different dimensions, and on understanding the causes of variability in deficit between participants.}, language = {en} } @article{HanneBurchertDeBleseretal.2015, author = {Hanne, Sandra and Burchert, Frank and De Bleser, Ria and Vasishth, Shravan}, title = {Sentence comprehension and morphological cues in aphasia: What eye-tracking reveals about integration and prediction}, series = {Journal of neurolinguistics : an international journal for the study of brain function in language behavior and experience}, volume = {34}, journal = {Journal of neurolinguistics : an international journal for the study of brain function in language behavior and experience}, publisher = {Elsevier}, address = {Oxford}, issn = {0911-6044}, doi = {10.1016/j.jneuroling.2014.12.003}, pages = {83 -- 111}, year = {2015}, abstract = {Comprehension of non-canonical sentences can be difficult for individuals with aphasia (IWA). It is still unclear to which extent morphological cues like case marking or verb inflection may influence IWA's performance or even help to override deficits in sentence comprehension. Until now, studies have mainly used offline methods to draw inferences about syntactic deficits and, so far, only a few studies have looked at online syntactic processing in aphasia. We investigated sentence processing in German-speaking IWA by combining an offline (sentence-picture matching) and an online (eye-tracking in the visual-world paradigm) method. Our goal was to determine whether IWA are capable of using inflectional morphology (number-agreement markers on verbs and case markers in noun phrases) as a cue to sentence interpretation. We report results of two visual-world experiments using German reversible SVO and OVS sentences. In each study, there were eight IWA and 20 age-matched controls. Experiment 1 targeted the role of unambiguous case morphology, while Experiment 2 looked at processing of number-agreement cues at the verb in caseambiguous sentences. IWA showed deficits in using both types of morphological markers as a cue to non-canonical sentence interpretation and the results indicate that in aphasia, processing of case-marking cues is more vulnerable as compared to verbagreement morphology. We ascribe this finding to the higher cue reliability of agreement cues, which renders them more resistant against impairments in aphasia. However, the online data revealed that IWA are in principle capable of successfully computing morphological cues, but the integration of morphological information is delayed as compared to age-matched controls. Furthermore, we found striking differences between controls and IWA regarding subject-before-object parsing predictions. While in case-unambiguous sentences IWA showed evidence for early subjectbefore-object parsing commitments, they exhibited no straightforward subject-first prediction in case-ambiguous sentences, although controls did so for ambiguous structures. IWA delayed their parsing decisions in case-ambiguous sentences until unambiguous morphological information, such as a subject-verbnumber-agreement cue, was available. We attribute the results for IWA to deficits in predictive processes based on morphosyntactic cues during sentence comprehension. The results indicate that IWA adopt a wait-and-see strategy and initiate prediction of upcoming syntactic structure only when unambiguous case or agreement cues are available. (C) 2015 Elsevier Ltd. All rights reserved.}, language = {en} } @article{PatilHanneBurchertetal.2016, author = {Patil, Umesh and Hanne, Sandra and Burchert, Frank and De Bleser, Ria and Vasishth, Shravan}, title = {A Computational Evaluation of Sentence Processing Deficits in Aphasia}, series = {Cognitive science : a multidisciplinary journal of anthropology, artificial intelligence, education, linguistics, neuroscience, philosophy, psychology ; journal of the Cognitive Science Society}, volume = {40}, journal = {Cognitive science : a multidisciplinary journal of anthropology, artificial intelligence, education, linguistics, neuroscience, philosophy, psychology ; journal of the Cognitive Science Society}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0364-0213}, doi = {10.1111/cogs.12250}, pages = {5 -- 50}, year = {2016}, abstract = {Individuals with agrammatic Broca's aphasia experience difficulty when processing reversible non-canonical sentences. Different accounts have been proposed to explain this phenomenon. The Trace Deletion account (Grodzinsky, 1995, 2000, 2006) attributes this deficit to an impairment in syntactic representations, whereas others (e.g., Caplan, Waters, Dede, Michaud, \& Reddy, 2007; Haarmann, Just, \& Carpenter, 1997) propose that the underlying structural representations are unimpaired, but sentence comprehension is affected by processing deficits, such as slow lexical activation, reduction in memory resources, slowed processing and/or intermittent deficiency, among others. We test the claims of two processing accounts, slowed processing and intermittent deficiency, and two versions of the Trace Deletion Hypothesis (TDH), in a computational framework for sentence processing (Lewis \& Vasishth, 2005) implemented in ACT-R (Anderson, Byrne, Douglass, Lebiere, \& Qin, 2004). The assumption of slowed processing is operationalized as slow procedural memory, so that each processing action is performed slower than normal, and intermittent deficiency as extra noise in the procedural memory, so that the parsing steps are more noisy than normal. We operationalize the TDH as an absence of trace information in the parse tree. To test the predictions of the models implementing these theories, we use the data from a German sentence—picture matching study reported in Hanne, Sekerina, Vasishth, Burchert, and De Bleser (2011). The data consist of offline (sentence-picture matching accuracies and response times) and online (eye fixation proportions) measures. From among the models considered, the model assuming that both slowed processing and intermittent deficiency are present emerges as the best model of sentence processing difficulty in aphasia. The modeling of individual differences suggests that, if we assume that patients have both slowed processing and intermittent deficiency, they have them in differing degrees.}, language = {en} } @article{PreglaLissonHernandezVasishthetal.2021, author = {Pregla, Dorothea and Liss{\´o}n Hern{\´a}ndez, Paula J. and Vasishth, Shravan and Burchert, Frank and Stadie, Nicole}, title = {Variability in sentence comprehension in aphasia in German}, series = {Brain \& language : a journal of the neurobiology of language}, volume = {222}, journal = {Brain \& language : a journal of the neurobiology of language}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0093-934X}, doi = {10.1016/j.bl.2021.105008}, pages = {20}, year = {2021}, abstract = {An important aspect of aphasia is the observation of behavioral variability between and within individual participants. Our study addresses variability in sentence comprehension in German, by testing 21 individuals with aphasia and a control group and involving (a) several constructions (declarative sentences, relative clauses and control structures with an overt pronoun or PRO), (b) three response tasks (object manipulation, sentence-picture matching with/without self-paced listening), and (c) two test phases (to investigate test-retest performance). With this systematic, large-scale study we gained insights into variability in sentence comprehension. We found that the size of syntactic effects varied both in aphasia and in control participants. Whereas variability in control participants led to systematic changes, variability in individuals with aphasia was unsystematic across test phases or response tasks. The persistent occurrence of canonicity and interference effects across response tasks and test phases, however, shows that the performance is systematically influenced by syntactic complexity.}, language = {en} }