A 'no' with a trace of 'yes': A mouse-tracking study of negative sentence processing.

There is strong evidence that comprehenders can parse sentences in an incremental fashion. However, when the sentence contains a negation, the evidence is less clear. Previous work has shown that increasing the pragmatic felicity of a negative sentence reduces or eliminates any processing overhead relative to affirmative sentences. However, in previous work felicity has gone hand-in-hand with the predictability of critical material in a sentence. In three experiments reported here, we presented equally felicitous sentences with critical material of varying predictability (operationalised as the number of possible completions) to test whether this might be a critical factor determining the ease with which partial sentences containing a negation are interpreted. Participants completed a truth-value judgement task (Experiment 1) or a sentence completion task (Experiments 2 and 3) after viewing a visual environment that provided the context for a test sentence, which could differ in truth value (in Experiment 1 only), polarity (affirmative or negative), and number of possible completions (one, two, or three). In all three experiments, we recorded response times and accuracy, but also response dynamics via participants' computer mouse trajectories, allowing us to test specific hypotheses about the time course of comprehension. Across all experiments, in conditions with one or two possible targets, we observed consistent detrimental effects of negative polarity, suggesting that the difficulty in processing negation cannot be reduced to effects relating to predictability or pragmatic felicity. We discuss this finding in relation to incremental and two-stage models of processing and outline a new account of the processing difficulty arising from negation in terms of a conflict between what is locally activated on the basis of individual words and phrases and the global meaning of a negative sentence.

Dissociable effects of prediction and integration during language comprehension: evidence from a large-scale study using brain potentials.

Composing sentence meaning is easier for predictable words than for unpredictable words. Are predictable words genuinely predicted, or simply more plausible and therefore easier to integrate with sentence context? We addressed this persistent and fundamental question using data from a recent, large-scale (n = 334) replication study, by investigating the effects of word predictability and sentence plausibility on the N400, the brain's electrophysiological index of semantic processing. A spatio-temporally fine-grained mixed-effect multiple regression analysis revealed overlapping effects of predictability and plausibility on the N400, albeit with distinct spatio-temporal profiles. Our results challenge the view that the predictability-dependent N400 reflects the effects of either prediction or integration, and suggest that semantic facilitation of predictable words arises from a cascade of processes that activate and integrate word meaning with context into a sentence-level meaning. This article is part of the theme issue 'Towards mechanistic models of meaning composition'.

Large-scale replication study reveals a limit on probabilistic prediction in language comprehension.

Do people routinely pre-activate the meaning and even the phonological form of upcoming words? The most acclaimed evidence for phonological prediction comes from a 2005 Nature Neuroscience publication by DeLong, Urbach and Kutas, who observed a graded modulation of electrical brain potentials (N400) to nouns and preceding articles by the probability that people use a word to continue the sentence fragment ('cloze'). In our direct replication study spanning 9 laboratories (N=334), pre-registered replication-analyses and exploratory Bayes factor analyses successfully replicated the noun-results but, crucially, not the article-results. Pre-registered single-trial analyses also yielded a statistically significant effect for the nouns but not the articles. Exploratory Bayesian single-trial analyses showed that the article-effect may be non-zero but is likely far smaller than originally reported and too small to observe without very large sample sizes. Our results do not support the view that readers routinely pre-activate the phonological form of predictable words.