Publications

Abstract

Current psycholinguistic theory proffers prediction as a central, explanatory mechanism in language
processing. However, widely-replicated prediction effects may not mean that prediction is
necessary in language processing. As a case in point, C. D. Martin et al. [2013. Bilinguals reading
in their second language do not predict upcoming words as native readers do.
Journal of
Memory and Language, 69
(4), 574
–
588. doi:10.1016/j.jml.2013.08.001] reported ERP evidence for
prediction in native- but not in non-native speakers. Articles mismatching an expected noun
elicited larger negativity in the N400 time window compared to articles matching the expected
noun in native speakers only. We attempted to replicate these findings, but found no evidence
for prediction irrespective of language nativeness. We argue that pre-activation of phonological
form of upcoming nouns, as evidenced in article-elicited effects, may not be a robust
phenomenon. A view of prediction as a necessary computation in language comprehension
must be re-evaluated.

Abstract

We used event-related potentials (ERP) to investigate whether Spanish−English bilinguals preactivate form and meaning of predictable words. Participants read high-cloze sentence contexts (e.g., “The student is going to the library to borrow a . . .”), followed by the predictable word (book), a word that was form-related (hook) or semantically related (page) to the predictable word, or an unrelated word (sofa). Word stimulus onset synchrony (SOA) was 500 ms (Experiment 1) or 700 ms (Experiment 2). In both experiments, all nonpredictable words elicited classic N400 effects. Form-related and unrelated words elicited similar N400 effects. Semantically related words elicited smaller N400s than unrelated words, which however, did not depend on cloze value of the predictable word. Thus, we found no N400 evidence for preactivation of form or meaning at either SOA, unlike native-speaker results (Ito, Corley et al., 2016). However, non-native speakers did show the post-N400 posterior positivity (LPC effect) for form-related words like native speakers, but only at the slower SOA. This LPC effect increased gradually with cloze value of the predictable word. We do not interpret this effect as necessarily demonstrating prediction, but rather as evincing combined effects of top-down activation (contextual meaning) and bottom-up activation (form similarity) that result in activation of unseen words that fit the context well, thereby leading to an interpretation conflict reflected in the LPC. Although there was no evidence that non-native speakers preactivate form or meaning, non-native speakers nonetheless appear to use bottom-up and top-down information to constrain incremental interpretation much like native speakers do.

Abstract

While structural priming makes a valuable contribution to psycholinguistics, it does not allow direct observation of representation, nor escape “source ambiguity.” Structural priming taps into implicit memory representations and processes that may differ from what is used online. We question whether implicit memory for language can and should be equated with linguistic representation or with language processing.

Abstract

The ability to use words to refer to the world is vital to the communicative power of human language. In particular, the anaphoric use of words to refer to previously mentioned concepts (antecedents) allows dialogue to be coherent and meaningful. Psycholinguistic theory posits that anaphor comprehension involves reactivating a memory representation of the antecedent. Whereas this implies the involvement of recognition memory, or the mnemonic sub-routines by which people distinguish old from new, the neural processes for reference resolution are largely unknown. Here, we report time-frequency analysis of four EEG experiments to reveal the increased coupling of functional neural systems associated with referentially coherent expressions compared to referentially problematic expressions. Despite varying in modality, language, and type of referential expression, all experiments showed larger gamma-band power for referentially coherent expressions compared to referentially problematic expressions. Beamformer analysis in high-density Experiment 4 localised the gamma-band increase to posterior parietal cortex around 400-600 ms after anaphor-onset and to frontaltemporal cortex around 500-1000 ms. We argue that the observed gamma-band power increases reflect successful referential binding and resolution, which links incoming information to antecedents through an interaction between the brain’s recognition memory networks and frontal-temporal language network. We integrate these findings with previous results from patient and neuroimaging studies, and we outline a nascent cortico-hippocampal theory of reference.

Abstract

How does knowledge of real-world events shape our understanding of incoming language? Do temporal terms like “before” and “after” impact the online recruitment of real-world event knowledge? These questions were addressed in two ERP experiments, wherein participants read sentences that started with “before” or “after” and contained a critical word that rendered each sentence true or false (e.g., “Before/After the global economic crisis, securing a mortgage was easy/harder”). The critical words were matched on predictability, rated truth value, and semantic relatedness to the words in the sentence. Regardless of whether participants explicitly verified the sentences or not, false-after-sentences elicited larger N400s than true-after-sentences, consistent with the well-established finding that semantic retrieval of concepts is facilitated when they are consistent with real-world knowledge. However, although the truth judgments did not differ between before- and after-sentences, no such sentence N400 truth value effect occurred in before-sentences, whereas false-before-sentences elicited an enhanced subsequent positive ERPs. The temporal term “before” itself elicited more negative ERPs at central electrode channels than “after.” These patterns of results show that, irrespective of ultimate sentence truth value judgments, semantic retrieval of concepts is momentarily facilitated when they are consistent with the known event outcome compared to when they are not. However, this inappropriate facilitation incurs later processing costs as reflected in the subsequent positive ERP deflections. The results suggest that automatic activation of event knowledge can impede the incremental semantic processes required to establish sentence truth value.

Abstract

People can establish whether a sentence is hypothetically true even if what it describes can never be literally true given the laws of the natural world. Two event-related potential (ERP) experiments examined electrophysiological responses to sentences about unrealistic counterfactual worlds that require people to construct novel conceptual combinations and infer their consequences as the sentence unfolds in time (e.g., “If dogs had gills…”). Experiment 1 established that without this premise, described consequences (e.g., “Dobermans would breathe under water …”) elicited larger N400 responses than real-world true sentences. Incorporation of the counterfactual premise in Experiment 2 generated similar N400 effects of propositional truth-value in counterfactual and real-world sentences, suggesting that the counterfactual context eliminated the interpretive problems posed by locally anomalous sentences. This result did not depend on cloze probability of the sentences. In contrast to earlier findings regarding online comprehension of logical operators and counterfactuals, these results show that ongoing processing can be directly impacted by propositional truth-value, even that of unrealistic counterfactuals.

Abstract

The animacy distinction is deeply rooted in the language faculty. A key example is differential object marking, the phenomenon where animate sentential objects receive specific marking. We used event-related potentials to examine the neural processing consequences of case-marking violations on animate and inanimate direct objects in Spanish. Inanimate objects with incorrect prepositional case marker ‘a’ (‘al suelo’) elicited a P600 effect compared to unmarked objects, consistent with previous literature. However, animate objects without the required prepositional case marker (‘el obispo’) only elicited an N400 effect compared to marked objects. This novel finding, an exclusive N400 modulation by a straightforward grammatical rule violation, does not follow from extant neurocognitive models of sentence processing, and mirrors unexpected “semantic P600” effects for thematically problematic sentences. These results may reflect animacy asymmetry in competition for argument prominence: following the article, thematic interpretation difficulties are elicited only by unexpectedly animate objects.