TY - JOUR A1 - Patil, Umesh A1 - Hanne, Sandra A1 - Burchert, Frank A1 - De Bleser, Ria A1 - Vasishth, Shravan T1 - A Computational Evaluation of Sentence Processing Deficits in Aphasia JF - Cognitive science : a multidisciplinary journal of anthropology, artificial intelligence, education, linguistics, neuroscience, philosophy, psychology ; journal of the Cognitive Science Society N2 - 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. KW - Aphasia KW - Non-canonical sentences KW - Sentence-picture matching KW - Eye movements KW - Computational modeling KW - Cognitive architecture KW - Individual differences Y1 - 2016 U6 - https://doi.org/10.1111/cogs.12250 SN - 0364-0213 SN - 1551-6709 VL - 40 SP - 5 EP - 50 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Mätzig, Paul A1 - Vasishth, Shravan A1 - Engelmann, Felix A1 - Caplan, David A1 - Burchert, Frank T1 - A computational investigation of sources of variability in sentence comprehension difficulty in aphasia JF - Topics in cognitive science N2 - 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. KW - Sentence comprehension KW - Aphasia KW - Computational modeling KW - Cue-based retrieval Y1 - 2018 U6 - https://doi.org/10.1111/tops.12323 SN - 1756-8757 SN - 1756-8765 VL - 10 IS - 1 SP - 161 EP - 174 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Hanne, Sandra A1 - Sekerina, Irina A. A1 - Vasishth, Shravan A1 - Burchert, Frank A1 - De Bleser, Ria T1 - Chance in agrammatic sentence comprehension what does it really mean? Evidence from eye movements of German agrammatic aphasic patients JF - Aphasiology : an international, interdisciplinary journal N2 - Background: In addition to the canonical subject-verb-object (SVO) word order, German also allows for non-canonical order (OVS), and the case-marking system supports thematic role interpretation. Previous eye-tracking studies (Kamide et al., 2003; Knoeferle, 2007) have shown that unambiguous case information in non-canonical sentences is processed incrementally. For individuals with agrammatic aphasia, comprehension of non-canonical sentences is at chance level (Burchert et al., 2003). The trace deletion hypothesis (Grodzinsky 1995, 2000) claims that this is due to structural impairments in syntactic representations, which force the individual with aphasia (IWA) to apply a guessing strategy. However, recent studies investigating online sentence processing in aphasia (Caplan et al., 2007; Dickey et al., 2007) found that divergences exist in IWAs' sentence-processing routines depending on whether they comprehended non-canonical sentences correctly or not, pointing rather to a processing deficit explanation. Aims: The aim of the current study was to investigate agrammatic IWAs' online and offline sentence comprehension simultaneously in order to reveal what online sentence-processing strategies they rely on and how these differ from controls' processing routines. We further asked whether IWAs' offline chance performance for non-canonical sentences does indeed result from guessing. Methods Procedures: We used the visual-world paradigm and measured eye movements (as an index of online sentence processing) of controls (N = 8) and individuals with aphasia (N = 7) during a sentence-picture matching task. Additional offline measures were accuracy and reaction times. Outcomes Results: While the offline accuracy results corresponded to the pattern predicted by the TDH, IWAs' eye movements revealed systematic differences depending on the response accuracy. Conclusions: These findings constitute evidence against attributing IWAs' chance performance for non-canonical structures to mere guessing. Instead, our results support processing deficit explanations and characterise the agrammatic parser as deterministic and inefficient: it is slowed down, affected by intermittent deficiencies in performing syntactic operations, and fails to compute reanalysis even when one is detected. KW - Eye movements KW - Non-canonical sentences KW - Agrammatic aphasia KW - Broca's aphasia KW - Chance performance KW - Online and offline processing KW - Sentence comprehension disorders KW - German syntax Y1 - 2011 U6 - https://doi.org/10.1080/02687038.2010.489256 SN - 0268-7038 VL - 25 IS - 2 SP - 221 EP - 244 PB - Wiley CY - Hove ER - TY - JOUR A1 - Lorenz, Antje A1 - Heide, Judith A1 - Burchert, Frank T1 - Compound naming in aphasia: effects of complexity, part of speech, and semantic transparency JF - Language, cognition and neuroscience KW - compound production KW - morphology KW - decomposition KW - lemma KW - part of speech KW - semantic transparency KW - aphasia KW - word-finding difficulties Y1 - 2014 U6 - https://doi.org/10.1080/01690965.2013.766357 SN - 2327-3798 SN - 2327-3801 VL - 29 IS - 1 SP - 88 EP - 106 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Vasishth, Shravan A1 - Nicenboim, Bruno A1 - Engelmann, Felix A1 - Burchert, Frank T1 - Computational Models of Retrieval Processes in Sentence Processing JF - Trends in Cognitive Sciences N2 - Sentence comprehension requires that the comprehender work out who did what to whom. This process has been characterized as retrieval from memory. This review summarizes the quantitative predictions and empirical coverage of the two existing computational models of retrieval and shows how the predictive performance of these two competing models can be tested against a benchmark data-set. We also show how computational modeling can help us better understand sources of variability in both unimpaired and impaired sentence comprehension. Y1 - 2019 U6 - https://doi.org/10.1016/j.tics.2019.09.003 SN - 1364-6613 SN - 1879-307X VL - 23 IS - 11 SP - 968 EP - 982 PB - Elsevier CY - London ER - TY - GEN A1 - Ciaccio, Laura Anna A1 - Burchert, Frank A1 - Semenza, Carlo T1 - Derivational morphology in agrammatic aphasia BT - a comparison between prefixed and suffixed words T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe N2 - Although a relatively large number of studies on acquired language impairments have tested the case of derivational morphology, none of these have specifically investigated whether there are differences in how prefixed and suffixed derived words are impaired. Based on linguistic and psycholinguistic considerations on prefixed and suffixed derived words, differences in how these two types of derivations are processed, and consequently impaired, are predicted. In the present study, we investigated the errors produced in reading aloud simple, prefixed, and suffixed words by three German individuals with agrammatic aphasia (NN, LG, SA). We found that, while NN and LG produced similar numbers of errors with prefixed and suffixed words, SA showed a selective impairment for prefixed words. Furthermore, NN and SA produced more errors specifically involving the affix with prefixed words than with suffixed words. We discuss our findings in terms of relative position of stem and affix in prefixed and suffixed words, as well as in terms of specific properties of prefixes and suffixes. KW - Broca’s aphasia KW - morphological decomposition KW - morphological errors KW - derivation KW - prefixes Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-473995 SN - 1866-8364 IS - 648 ER - TY - JOUR A1 - Ciaccio, Laura Anna A1 - Burchert, Frank A1 - Semenza, Carlo T1 - Derivational morphology in agrammatic aphasia BT - a comparison between prefixed and suffixed words JF - Frontiers in Psychology N2 - Although a relatively large number of studies on acquired language impairments have tested the case of derivational morphology, none of these have specifically investigated whether there are differences in how prefixed and suffixed derived words are impaired. Based on linguistic and psycholinguistic considerations on prefixed and suffixed derived words, differences in how these two types of derivations are processed, and consequently impaired, are predicted. In the present study, we investigated the errors produced in reading aloud simple, prefixed, and suffixed words by three German individuals with agrammatic aphasia (NN, LG, SA). We found that, while NN and LG produced similar numbers of errors with prefixed and suffixed words, SA showed a selective impairment for prefixed words. Furthermore, NN and SA produced more errors specifically involving the affix with prefixed words than with suffixed words. We discuss our findings in terms of relative position of stem and affix in prefixed and suffixed words, as well as in terms of specific properties of prefixes and suffixes. KW - Broca’s aphasia KW - morphological decomposition KW - morphological errors KW - derivation KW - prefixes Y1 - 2019 U6 - https://doi.org/10.3389/fpsyg.2020.01070 SN - 1664-1078 VL - 11 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Stahn, Corinna A1 - Hörning, Robin A1 - Burchert, Frank A1 - De Bleser, Ria T1 - Die aphasische Verarbeitung räumlicher Relationen Y1 - 2010 ER - TY - JOUR A1 - Stahn, Corinna A1 - Hörnig, Robin A1 - Burchert, Frank A1 - De Bleser, Ria T1 - Die aphasische Verarbeitung räumlicher Relationen JF - Spektrum Patholinguistik Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-47025 SN - 1866-9433 SN - 1866-9085 VL - 3 SP - 151 EP - 154 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Burchert, Frank A1 - De Bleser, Ria A1 - Sonntag, Katharina T1 - Does morphology make the difference? : Agrammatic sentence comprehension in German Y1 - 2003 ER -