Domain-general conflict monitoring predicts neural and behavioral indices of linguistic error processing during reading comprehension

The State of Cognitive Control in Language Processing

Understanding language requires readers and listeners to cull meaning from fast-unfolding messages that often contain conflicting cues pointing to incompatible ways of interpreting the input (e.g., "The cat was chased by the mouse"). This article reviews mounting evidence from multiple methods demonstrating that cognitive control plays an essential role in resolving conflict during language comprehension. How does cognitive control accomplish this task? Psycholinguistic proposals have conspicuously failed to address this question. We introduce an account in which cognitive control aids language processing when cues conflict by sending top-down biasing signals that strengthen the interpretation supported by the most reliable evidence available. We also provide a computationally plausible model that solves the critical problem of how cognitive control "knows" which way to direct its biasing signal by allowing linguistic knowledge itself to issue crucial guidance. Such a mental architecture can explain a range of experimental findings, including how moment-to-moment shifts in cognitive-control state-its level of activity within a person-directly impact how quickly and successfully language comprehension is achieved.

General cognitive processing for orthographic discrepancy engages foveal attention during sentence comprehension

Words are processed in the parafovea and fovea in succession during natural reading, but the classic rapid serial visual presentation (RSVP) paradigm presents words only in the fovea. Unlike the RSVP paradigm, the RSVP with flanker (RSVP-flanker) paradigm is similar to natural text reading. Previous studies using the RSVP-flanker paradigm have suggested that high-level semantic/syntactic integration engages foveal fixation after parafoveal semantic access. However, it is less clear how general cognitive processing, such as discrepancy monitoring and error correction, unfolds across the parafoveal and foveal visual fields. In the current study, Chinese sentences were presented with the RSVP-flanker paradigm. Critical words were manipulated so that they were expected (EXP), semantically violated (VIO), or orthographically similar (ORT). Because of the nuanced differences between the EXP and ORT conditions, the processing of ORT critical words required more general cognitive processing, such as discrepancy monitoring and error correction. In contrast, the processing of VIO words may require more semantic integration. The ERP results showed more positive foveal late positive component (LPC) in ORT versus VIO. Moreover, there was no parafoveal LPC effect, but a robust foveal LPC effect, in the contrasts of VIO/ORT versus EXP, replicating previous results. Together, the results provide substantial evidence that general cognitive processing for orthographic discrepancy occurs at the foveal perception.

Effect of Healthy Aging and Gender on Syntactic Input Processing: A P600 Event-Related Potential Study

PURPOSE

This study aimed to investigate the effect of healthy aging and gender, as well as the interaction, thereof, on syntactic input processing during sentence comprehension. This was achieved through the recording of the P600 event-related potential.

METHOD

Sixty Flemish (native speakers of Dutch) participants (30 men and 30 women), equally distributed into three age groups (young, middle-aged, and older adults), were subjected to a visually presented word order violation task under simultaneous electro-encephalography recording. The task contained 60 sentences, of which half were grammatical and half contained a word order violation. P600 responses were analyzed for amplitude, latency, topographical distribution, and source localization.

RESULTS

Regarding the effect of healthy aging, no age-related differences were found for the amplitude, onset latency, and topographical distribution of the P600 effect (difference wave). Although aging effects on the P600 effect amplitude were absent, a reduced P600 amplitude in response to both the grammatical and ungrammatical sentences was found, next to a reduced overall degree of source activation in linguistic regions of interest. Also, a reduced behavioral accuracy in response to the word order violation was observed in the older adults group. Regarding the effect of gender, females exhibited a larger P600 effect amplitude and a reduced behavioral accuracy compared to males. No gender-related differences were found for P600 effect onset latency, topographical distribution, and source activation.

CONCLUSIONS

While this study demonstrates no effect of aging on the P600 effect, the lower behavioral response and absence of any activation shift argues against functional compensation. Moreover, although increased neural activation in women combined with their reduced behavioral accuracy may indicate the use of different cognitive strategies in men and women, source localization analysis could not objectify this hypothesis.

Variation in how cognitive control modulates sentence processing

Prior research suggests that cognitive control can assist the comprehension of sentences that create conflict between interpretations, at least under some circumstances. However, the mixed pattern of results suggests that cognitive control may not always be necessary for accurate comprehension. We tested whether cognitive control recruitment for language processing is systematically variable, depending on the type of sentential ambiguity or conflict, individual differences in cognitive control, and task demands. Participants completed two sessions in a web-based experiment. The first session tested conflict modulation using interleaved Stroop and sentence comprehension trials. Critical sentences contained syntax-semantics or phrase-attachment conflict. In the second session, participants completed three cognitive control and three working memory tasks. Exploratory factor analysis was used to index individual differences in a cognitive control factor and a working memory factor. At the group level, there were no significant conflict modulation effects for either syntax-semantics or phrase-attachment conflict. At the individual differences level, the cognitive control factor correlated with offline comprehension accuracy but not online processing measures for both types of conflict. Together, the results suggest that the role of cognitive control in sentence processing may vary according to task demands. When overt decisions are required, individual differences in cognitive control may matter such that better cognitive control results in better language comprehension performance. The results add to the mixed evidence on conflict modulation and raise questions about the situations under which cognitive control influences online processing.

Greater entropy leads to more explicit referential forms during language production

Speakers can refer to previously-mentioned words (e.g., the actor) using attenuated referring expressions such as pronouns (he), or elaborated referential forms such as repeating the original word (the actor). Predictability is theorized to influence form of reference during language production: More attenuated forms may be used to refer to more predictable words, presumably because predictable words are already active in memory, and therefore require less linguistic signal during subsequent reference. However, the reported results are mixed. The current study examines the effect of entropy, an information-theoretic metric that captures the predictability of all, not just one, referential candidate, on the production of referential forms. A meta-analysis combining data from multiple experiments (492 participants, 405 items) revealed that greater entropy leads to more explicit referential forms, suggesting that entropy might intensify the competition between referential candidates during language production, reducing total memory activation.