@article{BostonHaleVasishthetal.2011, author = {Boston, Marisa Ferrara and Hale, John T. and Vasishth, Shravan and Kliegl, Reinhold}, title = {Parallel processing and sentence comprehension difficulty}, series = {Language and cognitive processes}, volume = {26}, journal = {Language and cognitive processes}, number = {3}, publisher = {Wiley}, address = {Hove}, issn = {0169-0965}, doi = {10.1080/01690965.2010.492228}, pages = {301 -- 349}, year = {2011}, abstract = {Eye fixation durations during normal reading correlate with processing difficulty, but the specific cognitive mechanisms reflected in these measures are not well understood. This study finds support in German readers' eye fixations for two distinct difficulty metrics: surprisal, which reflects the change in probabilities across syntactic analyses as new words are integrated; and retrieval, which quantifies comprehension difficulty in terms of working memory constraints. We examine the predictions of both metrics using a family of dependency parsers indexed by an upper limit on the number of candidate syntactic analyses they retain at successive words. Surprisal models all fixation measures and regression probability. By contrast, retrieval does not model any measure in serial processing. As more candidate analyses are considered in parallel at each word, retrieval can account for the same measures as surprisal. This pattern suggests an important role for ranked parallelism in theories of sentence comprehension.}, language = {en} } @article{HanneSekerinaVasishthetal.2011, author = {Hanne, Sandra and Sekerina, Irina A. and Vasishth, Shravan and Burchert, Frank and De Bleser, Ria}, title = {Chance in agrammatic sentence comprehension what does it really mean? Evidence from eye movements of German agrammatic aphasic patients}, series = {Aphasiology : an international, interdisciplinary journal}, volume = {25}, journal = {Aphasiology : an international, interdisciplinary journal}, number = {2}, publisher = {Wiley}, address = {Hove}, issn = {0268-7038}, doi = {10.1080/02687038.2010.489256}, pages = {221 -- 244}, year = {2011}, abstract = {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.}, language = {en} } @article{DrenhausZimmermannVasishth2011, author = {Drenhaus, Heiner and Zimmermann, Malte and Vasishth, Shravan}, title = {Exhaustiveness effects in clefts are not truth-functional}, series = {Journal of neurolinguistics : an international journal for the study of brain function in language behavior and experience}, volume = {24}, journal = {Journal of neurolinguistics : an international journal for the study of brain function in language behavior and experience}, number = {3}, publisher = {Elsevier}, address = {Oxford}, issn = {0911-6044}, doi = {10.1016/j.jneuroling.2010.10.004}, pages = {320 -- 337}, year = {2011}, abstract = {While it is widely acknowledged in the formal semantic literature that both the truth-functional focus particle only and it-clefts convey exhaustiveness, the nature and source of exhaustiveness effects with it-clefts remain contested. We describe a questionnaire study (n = 80) and an event-related brain potentials (ERP) study (n = 16) that investigated the violation of exhaustiveness in German only-foci versus it-clefts. The offline study showed that a violation of exhaustivity with only is less acceptable than the violation with it-clefts, suggesting a difference in the nature of exhaustivity interpretation in the two environments. The ERP-results confirm that this difference can be seen in online processing as well: a violation of exhaustiveness in only-foci elicited a centro-posterior positivity (600-800ms), whereas a violation in it-clefts induced a globally distributed N400 pattern (400-600ms). The positivity can be interpreted as a reanalysis process and more generally as a process of context updating. The N400 effect in it-clefts is interpreted as indexing a cancelation process that is functionally distinct from the only case. The ERP study is, to our knowledge, the first evidence from an online experimental paradigm which shows that the violation of exhaustiveness involves different underlying processes in the two structural environments.}, language = {en} } @article{vonderMalsburgVasishth2011, author = {von der Malsburg, Titus Raban and Vasishth, Shravan}, title = {What is the scanpath signature of syntactic reanalysis?}, series = {Journal of memory and language}, volume = {65}, journal = {Journal of memory and language}, number = {2}, publisher = {Elsevier}, address = {San Diego}, issn = {0749-596X}, doi = {10.1016/j.jml.2011.02.004}, pages = {109 -- 127}, year = {2011}, abstract = {Which repair strategy does the language system deploy when it gets garden-pathed, and what can regressive eye movements in reading tell us about reanalysis strategies? Several influential eye-tracking studies on syntactic reanalysis (Frazier \& Rayner, 1982; Meseguer, Carreiras, \& Clifton, 2002; Mitchell, Shen, Green, \& Hodgson, 2008) have addressed this question by examining scanpaths, i.e., sequential patterns of eye fixations. However, in the absence of a suitable method for analyzing scanpaths, these studies relied on simplified dependent measures that are arguably ambiguous and hard to interpret. We address the theoretical question of repair strategy by developing a new method that quantifies scanpath similarity. Our method reveals several distinct fixation strategies associated with reanalysis that went undetected in a previously published data set (Meseguer et al., 2002). One prevalent pattern suggests re-parsing of the sentence, a strategy that has been discussed in the literature (Frazier \& Rayner, 1982); however, readers differed tremendously in how they orchestrated the various fixation strategies. Our results suggest that the human parsing system non-deterministically adopts different strategies when confronted with the disambiguating material in garden-path sentences.}, language = {en} } @article{BartekLewisVasishthetal.2011, author = {Bartek, Brian and Lewis, Richard L. and Vasishth, Shravan and Smith, Mason R.}, title = {In Search of on-line locality effects in sentence comprehension}, series = {Journal of experimental psychology : Learning, memory, and cognition}, volume = {37}, journal = {Journal of experimental psychology : Learning, memory, and cognition}, number = {5}, publisher = {American Psychological Association}, address = {Washington}, issn = {0278-7393}, doi = {10.1037/a0024194}, pages = {1178 -- 1198}, year = {2011}, abstract = {Many comprehension theories assert that increasing the distance between elements participating in a linguistic relation (e.g., a verb and a noun phrase argument) increases the difficulty of establishing that relation during on-line comprehension. Such locality effects are expected to increase reading times and are thought to reveal properties and limitations of the short-term memory system that supports comprehension. Despite their theoretical importance and putative ubiquity, however, evidence for on-line locality effects is quite narrow linguistically and methodologically: It is restricted almost exclusively to self-paced reading of complex structures involving a particular class of syntactic relation. We present 4 experiments (2 self-paced reading and 2 eyetracking experiments) that demonstrate locality effects in the course of establishing subject-verb dependencies; locality effects are seen even in materials that can be read quickly and easily. These locality effects are observable in the earliest possible eye-movement measures and are of much shorter duration than previously reported effects. To account for the observed empirical patterns, we outline a processing model of the adaptive control of button pressing and eye movements. This model makes progress toward the goal of eliminating linking assumptions between memory constructs and empirical measures in favor of explicit theories of the coordinated control of motor responses and parsing.}, language = {en} } @article{BostonHalbeVasishthetal.2011, author = {Boston, Marisa Ferrara and Halbe, John T. and Vasishth, Shravan and Kliegl, Reinhold}, title = {Parallel processing and entence comprehension difficulty}, doi = {10.1080/01690965.2010.492228}, year = {2011}, abstract = {Eye fixation durations during normal reading correlate with processing difficulty, but the specific cognitive mechanisms reflected in these measures are not well understood. This study finds support in German readers' eye fixations for two distinct difficulty metrics: surprisal, which reflects the change in probabilities across syntactic analyses as new words are integrated; and retrieval, which quantifies comprehension difficulty in terms of working memory constraints. We examine the predictions of both metrics using a family of dependency parsers indexed by an upper limit on the number of candidate syntactic analyses they retain at successive words. Surprisal models all fixation measures and regression probability. By contrast, retrieval does not model any measure in serial processing. As more candidate analyses are considered in parallel at each word, retrieval can account for the same measures as surprisal. This pattern suggests an important role for ranked parallelism in theories of sentence comprehension.}, language = {en} } @book{VasishthBroe2011, author = {Vasishth, Shravan and Broe, Michael}, title = {The foundations of statistics: a simulation-based approach}, publisher = {Springer-Verlag Berlin Heidelberg}, address = {Berlin, Heidelberg}, isbn = {978-3-642-16312-8}, doi = {10.1007/978-3-642-16313-5}, pages = {178 S.}, year = {2011}, language = {en} }