A Direct Comparison of N400 Effects of Predictability and Incongruity in Adjective-Noun Combination

Abstract

*Previous work has shown that the N400 ERP component is elicited by all words, whether presented in isolation or in structured contexts, and that its amplitude is modulated by semantic association and contextual predictability. What is less clear is the extent to which the N400 response is modulated by semantic incongruity when predictability is held constant. In the current study we examine N400 modulation associated with independent manipulations of predictability and congruity in an adjective-noun paradigm that allows us to precisely control predictability through corpus counts. Our results demonstrate small N400 effects of semantic congruity (yellow bag vs. innocent bag), and much more robust N400 effects of predictability (runny nose vs. dainty nose) under the same conditions. These data argue against unitary N400 theories according to which N400 effects of both predictability and incongruity reflect a common process such as degree of integration difficulty, as large N400 effects of predictability were observed in the absence of large N400 effects of incongruity. However, the data are consistent with some versions of unitary 'facilitated access' N400 theories, as well as multiple-generator accounts according to which the N400 can be independently modulated by facilitated conceptual/lexical access (as with predictability) and integration difficulty (as with incongruity, perhaps to a greater extent in full sentential contexts).

A Tale of Two Positivities and the N400: Distinct neural signatures are evoked by confirmed and violated predictions at different levels of representation

“…Of course, it is possible that, in some situations, the detection of mismatch at the event level may be reflected by additional activity that may be visible within the N400 time window (e.g. Nieuwland et al, in press;Lau et al 2016). Regardless, our primary point is that any effects of plausibility on the N400 itself can ultimately stem from the same semantic predictive mechanism that give rise to the effects of cloze probability on the N400.…”

“…One argument that some have raised in favor of an integration account of the N400 is that its amplitude can be sensitive to the implausibility of the resulting interpretation (although this is by no means always the case, see Kuperberg, 2016, andShetreet et al, 2019, Supplementary Materials section 3 for recent review and discussion). The assumption is that, having accessed a lexical item, it takes more combinatorial work to construct an implausible/incoherent proposition than a plausible/coherent proposition (see Lau, Namyst, Fogel & Delgado, 2016;Nieuwland et al, in press). The amplitude of the N400 is, in part, taken to reflect this additional work.…”

On the predictability of event boundaries in discourse: An ERP investigation

“…According to this view, N400 effects of predictability are generated by retrieval mechanisms and reflect the degree to which the preceding context activates conceptual knowledge associated with the eliciting word though mechanisms such as lexical or event schemas priming (e.g., Chow & Phillips, 2013;Chwilla & Kolk, 2005;Lau et al, 2016). In the current study, the N400 effect of event boundary suggests that the conceptual knowledge activated by the context primes fine boundary targets more than coarse boundary targets.…”

“…While the functional interpretation of the N400 is still a matter of debate (e.g., Lau, Namyst, Fogel, & Delgado, 2016;Lau et al, 2008, for an overview see Kutas & Federmeier, 2011), there is growing consensus that N400 amplitude indexes processes associated with the ease of accessing and retrieving conceptual knowledge stored in long-term memory (e.g., Brouwer et al, 2012;Federmeier & Kutas, 1999;Kutas & Federmeier, 2000;Lau, Almeida, Hines, & Poeppel, 2009;Thornhill & van Petten, 2012). According to this view, N400 effects of predictability are generated by retrieval mechanisms and reflect the degree to which the preceding context activates conceptual knowledge associated with the eliciting word though mechanisms such as lexical or event schemas priming (e.g., Chow & Phillips, 2013;Chwilla & Kolk, 2005;Lau et al, 2016).…”

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

“…Compared to a less plausible word, a more plausible word might be easier to integrate with the context and general world knowledge into a sentence-level interpretation (e.g., [8][9]), regardless of whether word meaning had already been activated before it appeared. If such integration processes are reflected in EEG activity in the N400 time window along with processes of semantic activation [10][11], then the canonical pattern observed for predictability might in part reflect contributions of sentence plausibility.…”