The onset and time course of semantic priming during rapid recognition of visual words

Mask-related costs in measuring preview benefit: Evidence from a distributional analysis based on target word reading times

Skilled reading involves processing the upcoming word in parafoveal vision before it is fixated, leading to shorter fixations on that word. This phenomenon, parafoveal preview benefit, is a key component of theoretical models of reading; it is measured using the invisible boundary paradigm, in which reading times on a target word are compared for instances when preview is accurate and when the target word is masked while in the parafovea. However, parafoveal masks have been shown to induce unintentional processing costs, thereby inflating measures of preview benefit. The degraded mask has been explored as a potential solution to this problem, leading to mixed results. While previous work has analyzed the preview effect by comparing mean reading times on the target word, the present study provides a more comprehensive analysis by examining the distribution of the preview effect across target word fixation times for unrelated and degraded masks. Participants read sentences containing target words whose preview was either identical, unrelated, or degraded, and their eye movements were recorded. Analyses revealed that although there were no mean differences between reading times for the unrelated and degraded conditions, the pattern of the effects varied as a function of target word fixation times. Unrelated masks resulted in positively sloped generally linear delta plots, while degraded masks resulted in relatively flat delta plots for fixations longer than 200 ms. These differences suggest that different cognitive mechanisms are involved in the processing of the two mask types. Implications for understanding and measuring preview benefit are discussed.

Rapid Interactions of Widespread Brain Networks Characterize Semantic Cognition

Language comprehension requires the rapid retrieval and integration of contextually appropriate concepts ("semantic cognition"). Current neurobiological models of semantic cognition are limited by the spatial and temporal restrictions of single-modality neuroimaging and lesion approaches. This is a major impediment given the rapid sequence of processing steps that have to be coordinated to accurately comprehend language. Through the use of fused functional magnetic resonance imaging and electroencephalography analysis in humans (n = 26 adults; 15 females), we elucidate a temporally and spatially specific neurobiological model for real-time semantic cognition. We find that semantic cognition in the context of language comprehension is supported by trade-offs between widespread neural networks over the course of milliseconds. Incorporation of spatial and temporal characteristics, as well as behavioral measures, provide convergent evidence for the following progression: a hippocampal/anterior temporal phonological semantic retrieval network (peaking at ∼300 ms after the sentence final word); a frontotemporal thematic semantic network (∼400 ms); a hippocampal memory update network (∼500 ms); an inferior frontal semantic syntactic reappraisal network (∼600 ms); and nodes of the default mode network associated with conceptual coherence (∼750 ms). Additionally, in typical adults, mediatory relationships among these networks are significantly predictive of language comprehension ability. These findings provide a conceptual and methodological framework for the examination of speech and language disorders, with additional implications for the characterization of cognitive processes and clinical populations in other cognitive domains.SIGNIFICANCE STATEMENT The present study identifies a real-time neurobiological model of the meaning processes required during language comprehension (i.e., "semantic cognition"). Using a novel application of fused magnetic resonance imaging and electroencephalography in humans, we found that semantic cognition during language comprehension is supported by a rapid progression of widespread neural networks related to meaning, meaning integration, memory, reappraisal, and conceptual cohesion. Relationships among these systems were predictive of individuals' language comprehension efficiency. Our findings are the first to use fused neuroimaging analysis to elucidate language processes. In so doing, this study provides a new conceptual and methodological framework in which to characterize language processes and guide the treatment of speech and language deficits/disorders.

The role of selective attention in the positivity offset: Evidence from event related potentials

Some research suggests that positive and negative valence stimuli may be processed differently. For example, negative material may capture and hold attention more readily than equally arousing positive material. This is called the negativity bias, and it has been observed as both behavioural and electroencephalographic (EEG) effects. Consequently, it has been attributed to both automatic and elaborative processes. However, at the lowest levels of arousal, faster reaction times and stronger EEG responses to positive material have been observed. This is called the positivity offset, and the underlying cognitive mechanism is less understood. To study the role of selective attention in the positivity offset, participants completed a negative affective priming (NAP) task modified to dissociate priming for positive and negative words. The task required participants to indicate the valence of a target word, while simultaneously ignoring a distractor. In experiment 1, a behavioural facilitation effect (faster response time) was observed for positive words, in stark contrast to the original NAP task. These results were congruent with a previously reported general categorization advantage for positive material. In experiment 2, participants performed the task while EEG was recorded. In additional to replicating the behavioural results from experiment 1, positive words elicited a larger Late Positive Potential (LPP) component on ignored repetition relative to control trials. Surprisingly, negative words elicited a larger LPP than positive words on control trials. These results suggest that the positivity offset may reflect a greater sensitivity to priming effects due to a more flexible attentional set.

How well do word recognition measures correlate? Effects of language context and repeated presentations

In the present study we assessed the extent to which different word recognition time measures converge, using large databases of lexical decision times and eyetracking measures. We observed a low proportion of shared variance between these measures, which limits the validity of lexical decision times to real-life reading. We further investigated and compared the role of word frequency and length, two important predictors of word-processing latencies in these paradigms, and found that they influenced the measures to different extents. A second analysis of two different eyetracking corpora compared the eyetracking reading times for short paragraphs with those from reading of an entire book. Our results revealed that the correlations between eyetracking reading times of identical words in two different corpora are also low, suggesting that the higher-order language context in which words are presented plays a crucial role. Finally, our findings indicate that lexical decision times better resemble the average processing time of multiple presentations of the same word, across different language contexts.

Survival analyses reveal how early phonological processing affects eye movements during reading

Numerous studies have provided evidence that readers generate phonological codes while reading. However, a central question in much of this research has been how early these codes are generated. Answering this question has implications for the roles that phonological coding might play for skilled readers, especially whether phonological codes affect the identification of most words, which can only be the case if these codes are generated rapidly. To investigate the time course of phonological coding during silent reading, the present series of experiments examined survival analyses of first-fixation durations on phonologically related (homophones, pseudohomophones) and orthographic control (orthographically matched words and nonwords) stimuli that were either embedded in sentences in place of correct targets (Experiments 1 and 2) or presented as parafoveal previews for correct targets using the boundary paradigm (Experiments 3 and 4). Survival analyses revealed a discernible difference between processing the phonologically related versus the orthographic control items by as early as 160 ms from the start of fixation on average (160-173 ms across experiments). Because only approximately 18% of first fixation durations were shorter than these mean estimates and follow-up tests revealed that earlier divergence point estimates were associated with shorter gaze durations (e.g., more rapid word identification), results suggest that skilled readers rapidly generate phonological codes during normal, silent reading and that these codes may affect the identification of most words. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Print exposure modulates the effects of repetition priming during sentence reading

Individual readers vary greatly in the quality of their lexical representations, and consequently in how quickly and efficiently they can access orthographic and lexical knowledge. This variability may be explained, at least in part, by individual differences in exposure to printed language, because practice at reading promotes the development of stronger reading skills. In the present eyetracking experiment, we tested the hypothesis that the efficiency of word recognition during reading improves with increases in print exposure, by determining whether the magnitude of the repetition-priming effect is modulated by individual differences in scores on the author recognition test (ART). Lexical repetition of target words was manipulated across pairs of unrelated sentences that were presented on consecutive trials. The magnitude of the repetition effect was modulated by print exposure in early measures of processing, such that the magnitude of the effect was inversely related to scores on the ART. The results showed that low levels of print exposure, and thus lower-quality lexical representations, are associated with high levels of difficulty recognizing words, and thus with the greatest room to benefit from repetition. Furthermore, the interaction between scores on the ART and repetition suggests that print exposure is not simply an index of general reading speed, but rather that higher levels of print exposure are associated with an enhanced ability to access lexical knowledge and recognize words during reading.