Individual differences in reading fluency in Schizophrenia: Evidence from eye movements and fixation-related potentials

Readers with Schizophrenia (Sz) show decreased reading fluency, which negatively impacts both social and occupational outcomes. This talk will present an ongoing line of work that integrates eye tracking, EEG, and computational modeling, to investigate individual differences in reading fluency in readers with and without Schizophrenia. Our findings suggest that both higher-level (e.g., lexical) and lower-level (e.g., oculomotor and visual) processes contribute to slower reading fluency in readers with Schizophrenia. Compared to a control group, readers with Sz show reduced fixation-P1 amplitudes, longer fixation durations, fewer skipped words, and large increases in refixation rates (i.e., the probability of fixating on a word more than once). Also, as evidence that readers with Sz are making more refixations to compensate for reductions in parafoveal processing, their refixations landed closer to the center of the word (i.e., the optimal viewing location) compared to the control group. Building on these findings, simulations using the E-Z Reader model of eye movement control during reading also indicated that reduced reading fluency in Schizophrenia reflects changes to both high- and low-level processing. This talk will discuss how these findings can provide empirical constraints for the development of eye movement control models that better account for individual differences during reading.

Conspiracy Theories, Misinformation, and Sincerity of Belief Reports

A key assumption of psychological research on belief in conspiracy theories and other forms of misinformation is that participants provide sincere belief reports. However, this talk presents new empirical research suggesting that insincerely claiming to believe in misinformation while participating in psychology studies might be quite common.

Rob will also facilitate some discussion about whether there might be scope for using eye-trackers to study whether or not people believe statements that they read during the discussion.

The role of semantic interpretability and syntactic legality in complex nonword recognition

This study explored the role of semantic interpretability and syntactic legality on complex nonword recognition. A rating experiment tested the correlation between these twolinguistic factors by asking participants to rate the interpretability of legal and illegal nonwords made up of stem-suffix combinations. Results showed that these two factors are highly correlated. In two further lexical decision experiments (unprimed lexical decision in Experiment 2 and masked primed lexical decision in Experiment 3), we carefully dissociated interpretability and legality by comparing four types of nonwords: high-interpretability syntactically legal, high-interpretability syntactically illegal, low-interpretability syntactically legal, and low-interpretability syntactically illegal nonwords. To test whether or not the activation of embedded stems was modulated by their morpho-semantic and morpho-syntactic context, all complex nonwords were compared against a matched non-stem control.  A significant effect of stem status was found in Experiments 2 and 3, providing evidence for the important role of embedded stems in complex nonword recognition. Moreover, a significant effect of interpretability was found only in the unprimed lexical decision (Experiment 2), but not in masked priming (Experiment 3), suggesting that semantics does not influence complex word recognition until participants have enough time to thoroughly process the nonword. No effect of syntactic legality was found in either experiment. These results highlight the independent roles of semantic interpretability and syntactic legality in visual nonword recognition, supporting an initial semantically blind stage in morphological parsing.

Causes and consequences of misinformation during reading: Insights from eye tracking

People frequently rely on information even after it has been retracted, a phenomenon known as the continued-influence effect (CIE) of misinformation. This research uses eye tracking to investigate the cognitive processes underlying the CIE during reading. The eye movements of 85 participants were recorded as they read pairs of short newspaper-style articles containing a critical piece of information that was either retracted or not. Participants subsequently completed a comprehension questionnaire that tested their memory for general and critical details as well as inferential judgements related to the retracted information. To determine whether the CIE is modulated by individual differences in cognition, participants also completed tests of their language proficiency and working memory ability. The results of the comprehension questionnaire replicated previous evidence that repetition of the original information improved recall memory of the event. Linear mixed-effects models assessed the impact of misinformation and individual differences on readers’ eye movements across early and late stages of processing. The results provide insights into the cognitive causes and consequences of the CIE during reading. Implications for the development of effective interventions to reduce effects of misinformation will be discussed.

What can emotion and abstract words tell us about subjective semantic ratings?

Semantic dimensions such as context availability, imageability and valence, form core components of many theoretical accounts of lexical processing. Typically, normative data for such semantic dimensions are drawn from subjective ratings, however, questions have been raised regarding the reliability and validity of these ratings. In this talk, I will discuss this issue with a focus on context availability norms. Using data collected for another study, we show that context availability ratings required significantly higher rates of data exclusions at the level of both participants and items compared to other variables. In addition, high standard deviations at the item level, indicated a substantial degree of disagreement between participants. Recommendations will be discussed  for norm collection procedures more broadly in order that the validity of such norms can be improved. In particular, clear guidelines are required for data cleaning in order that the reliability of such norms is maximised and to facilitate replication across studies.

Direct lexical control of eye movements in Chinese reading: Evidence from the co-registration of EEG and eye tracking

The direct-lexical-control hypothesis stipulates that some aspect of a word’s processing determines the duration of the fixation on that word and/or the next. Although direct lexical control is incorporated into most current models of eye-movement control in reading, conclusive empirical evidence supporting this hypothesis is lacking to date. In this article, we report the results of an eye-tracking experiment using the boundary paradigm in which native speakers of Chinese read sentences in which target words were either high- or low-frequency and preceded by a valid or invalid preview. Eye movements were co-registered with electroencephalography, allowing standard analyses of eye-movement measures, divergence point analyses of fixation-duration distributions, and fixated-related potentials on the target words. These analyses collectively provide strong behavioral and neural evidence of early lexical processing and thus strong support for the direct-lexical-control hypothesis. 

Using MEG and Eye-Tracking to Examine the Eye-Mind Link During Reading

A core assumption of serial-attention models of eye-movement control during reading is that the completion of some stage of the lexical processing of word N is what initiates the programming of a saccade to move the eyes to word N+1 (Reichle, 2021).  To test this assumption, an MEG experiment was conducted in which participants made lexical decisions about pairs of simultaneously displayed letter strings, with one being displayed in central vision and the other being randomly displayed in left or right peripheral vision, and with the letter strings being high-frequency words, low-frequency words, or non-words.  Participants’ eye movements were recorded to identify saccade onsets from the central to peripheral letter strings, allowing for the interpretation of the MEG-measured cortical activity associated with processing the centrally displayed words (as indexed by differences related to processing the high- vs. low-frequency words) over an interval spanning their display onset to saccade onset.  The results provide physiological evidence for a strong eye-mind link, consistent with the assumption of serial-attention models that lexical processing is the “engine” driving eye movements during reading.