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Difficulties in saying the right word at the right time arise at least in part because multiple response candidates are simultaneously activated in the speaker's mind. The word selection process has been simulated using the picture–word interference task, in which participants name pictures while ignoring a superimposed written distractor word. However, words are usually produced in context, in the service of achieving a communicative goal. Two experiments addressed the questions whether context influences word production, and if so, how. We embedded the picture–word interference task in a dialogue-like setting, in which participants heard a question and named a picture as an answer to the question while ignoring a superimposed distractor word. The conversational context was either constraining or nonconstraining towards the answer. Manipulating the relationship between the picture name and the distractor, we focused on two core processes of word production: retrieval of semantic representations (Experiment 1) and phonological encoding (Experiment 2). The results of both experiments showed that naming reaction times (RTs) were shorter when preceded by constraining contexts as compared with nonconstraining contexts. Critically, constraining contexts decreased the effect of semantically related distractors but not the effect of phonologically related distractors. This suggests that conversational contexts can help speakers with aspects of the meaning of to-be-produced words, but phonological encoding processes still need to be performed as usual. [ABSTRACT FROM AUTHOR]

In two ERP experiments, we investigated how the Dutch discourse markers eigenlijk "actually", signalling expectation disconfirmation, and inderdaad "indeed", signalling expectation confirmation, affect incremental dialogue comprehension. We investigated their effects on the processing of subsequent (un)predictable words, and on the quality of word representations in memory. Participants read dialogues with (un)predictable endings that followed a discourse marker (eigenlijk in Experiment 1, inderdaad in Experiment 2) or a control adverb. We found no strong evidence that discourse markers modulated online predictability effects elicited by subsequently read words. However, words following eigenlijk elicited an enhanced posterior post-N400 positivity compared with words following an adverb regardless of their predictability, potentially reflecting increased processing costs associated with pragmatically driven discourse updating. No effects of inderdaad were found on online processing, but inderdaad seemed to influence memory for (un)predictable dialogue endings. These findings nuance our understanding of how pragmatic markers affect incremental language comprehension. [ABSTRACT FROM AUTHOR]

Different frequency bands in the electroencephalogram are postulated to support distinct language functions. Studies have suggested that alpha–beta power decreases may index word‐retrieval processes. In context‐driven word retrieval, participants hear lead‐in sentences that either constrain the final word ('He locked the door with the') or not ('She walked in here with the'). The last word is shown as a picture to be named. Previous studies have consistently found alpha–beta power decreases prior to picture onset for constrained relative to unconstrained sentences, localised to the left lateral‐temporal and lateral‐frontal lobes. However, the relative contribution of temporal versus frontal areas to alpha–beta power decreases is unknown. We recorded the electroencephalogram from patients with stroke lesions encompassing the left lateral‐temporal and inferior‐parietal regions or left‐lateral frontal lobe and from matched controls. Individual participant analyses revealed a behavioural sentence context facilitation effect in all participants, except for in the two patients with extensive lesions to temporal and inferior parietal lobes. We replicated the alpha–beta power decreases prior to picture onset in all participants, except for in the two same patients with extensive posterior lesions. Thus, whereas posterior lesions eliminated the behavioural and oscillatory context effect, frontal lesions did not. Hierarchical clustering analyses of all patients' lesion profiles, and behavioural and electrophysiological effects identified those two patients as having a unique combination of lesion distribution and context effects. These results indicate a critical role for the left lateral‐temporal and inferior parietal lobes, but not frontal cortex, in generating the alpha–beta power decreases underlying context‐driven word production. In context‐driven word retrieval, people hear incomplete sentences and name a picture that completes it. Semantically constraining sentence contexts facilitate picture naming and yield alpha–beta power decreases pre‐picture onset. Left temporal‐ and inferior‐parietal lesions eliminate behavioural and alpha–beta context effects, but left frontal lesions do not, indicating a critical role for posterior regions in generating the alpha–beta power decreases underlying context‐driven word production. [ABSTRACT FROM AUTHOR]

Despite strong evidence for prediction during language comprehension, the underlying mechanisms, and the extent to which they are specific to language, remain unclear. Re-analysing an event-related potentials study, we examined responses in the time-frequency domain to expected and unexpected (but plausible) words in strongly and weakly constraining sentences, and found results similar to those reported in nonverbal domains. Relative to expected words, unexpected words elicited an increase in the theta band (4–7 Hz) in strongly constraining contexts, suggesting the involvement of control processes to deal with the consequences of having a prediction disconfirmed. Prior to critical word onset, strongly constraining sentences exhibited a decrease in the alpha band (8–12 Hz) relative to weakly constraining sentences, suggesting that comprehenders can take advantage of predictive sentence contexts to prepare for the input. The results suggest that the brain recruits domain-general preparation and control mechanisms when making and assessing predictions during sentence comprehension. [ABSTRACT FROM PUBLISHER]

During language comprehension, semantic contextual information is used to generate expectations about upcoming items. This has been commonly studied through the N400 event-related potential (ERP), as a measure of facilitated lexical retrieval. However, the associative relationships in multi-word expressions (MWE) may enable the generation of a categorical expectation, leading to lexical retrieval before target word onset. Processing of the target word would thus reflect a target-identification mechanism, possibly indexed by a P3 ERP component. However, given their time overlap (200-500ms post-stimulus onset), differentiating between N400/P3 ERP responses (averaged over multiple linguistically variable trials) is problematic. In the present study, we analyzed EEG data from a previous experiment, which compared ERP responses to highly expected words that were placed either in a MWE or a regular non-fixed compositional context, and to low predictability controls. We focused on oscillatory dynamics and regression analyses, in order to dissociate between the two contexts by modeling the electrophysiological response as a function of item-level parameters. A significant interaction between word position and condition was found in the regression model for power in a theta range (~7-9Hz), providing evidence for the presence of qualitative differences between conditions. Power levels within this band were lower for MWE than compositional contexts when the target word appeared later on in the sentence, confirming that in the former lexical retrieval would have taken place before word onset. On the other hand, gamma-power (~50-70 Hz) was also modulated by predictability of the item in all conditions, which is interpreted as an index of a similar "matching" sub-step for both types of contexts, binding an expected representation and the external input. [ABSTRACT FROM AUTHOR]